diff --git a/docs/superpowers/specs/2026-06-30-playback-speed-slider-design.md b/docs/superpowers/specs/2026-06-30-playback-speed-slider-design.md
new file mode 100644
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--- /dev/null
+++ b/docs/superpowers/specs/2026-06-30-playback-speed-slider-design.md
@@ -0,0 +1,133 @@
+# Playback Speed slider (replaces "Reduce motion") — design
+
+**Date:** 2026-06-30
+**Status:** Approved (pending written-spec review)
+**Scope:** Frontend only (`simulator/static/`). No engine, pipeline, or media changes.
+
+## Summary
+
+Add a continuous **Playback Speed** slider (−2× … 2×) that controls the resting
+**altitude loop video** (`#vid-loop`) in real time as the user drags it. Below
+`0×` the loop plays **in reverse**. The slider **replaces** the "Reduce motion"
+toggle in the Output panel — but the reduced-motion *accessibility behavior* is
+preserved, now derived silently from the OS `prefers-reduced-motion` setting
+rather than a visible toggle.
+
+## What it affects (and what it does not)
+
+- **Affects:** the resting **altitude loop video** `#vid-loop` — the clip that
+  loops while parked at an altitude. The slider sets its play speed/direction.
+- **Does NOT affect:** the **morph / transition video** `#vid`. That element is
+  scrub-driven — the altitude dial sets its `currentTime` directly — so a
+  playback rate has no meaning there. Speed control never touches it.
+
+## UI
+
+Replace the `reduce-motion` checkbox `<label>` in `index.html` with a range
+slider, styled like the existing Audio level control:
+
+```
+Speed   [ −2 ········●········ 2 ]   1.37×
+```
+
+- `<input type="range" id="play-speed" min="-2" max="2" step="any" value="1">`
+  — `step="any"` so dragging yields a **continuous** value, not 0.25 detents.
+- A live numeric **readout** (`<span id="play-speed-val">`) shows the current
+  value formatted to 2 decimals with a `×` suffix (e.g. `1.37×`, `−0.75×`,
+  `0.00×`).
+- Reference **tick labels** at the nice increments (`−2 −1.75 … 0 … 2`) via a
+  `<datalist>` bound to the input, so the round numbers are visible without
+  quantizing the actual applied value.
+- New i18n key `speed.label` ("Speed") in en/es/fr/ja. The `rm.label` key is
+  retired.
+
+## Accessibility (preserved, now invisible)
+
+The reduce-motion *toggle* is removed, but its *behavior* is kept. `isReduced()`
+now derives **live from the OS setting only** —
+`matchMedia("(prefers-reduced-motion: reduce)")`, re-read on its `change` event —
+with no stored override and no UI. Every existing `isReduced()` call site keeps
+working unchanged:
+
+- loop-play gate (`playLoop`),
+- instant (no-tween) auto altitude transitions (`autoScrub`),
+- the photosensitivity-flash luminance floor.
+
+Consequences:
+
+- The `hef.reduceMotion` localStorage key (`RM_KEY`) is **retired**.
+- When OS reduced-motion is **active**: the loop stays frozen and the speed
+  slider is **disabled** (with a short hint), so a vestibular/photosensitive
+  visitor never gets motion they did not ask for. If the OS pref toggles at
+  runtime, the slider enables/disables to match.
+- `warn.body` copy (all 4 langs) is reworded: it currently tells users to "turn
+  on Reduce motion in the panel," which no longer exists. New copy points to the
+  system reduced-motion setting (now auto-applied).
+
+## Speed behavior (`app.js`)
+
+A new `applyPlaySpeed(speed)` drives `#vid-loop`, with the chosen value persisted
+to `localStorage["hef.playSpeed"]` (default `1`). Applied live on the slider's
+`input` event:
+
+- **speed > 0** → `loopVid.playbackRate = speed`; native forward play. The
+  existing duration→`loopStartFrame()` wrap is unchanged. Any active manual
+  reverse loop is cancelled.
+- **|speed| ≈ 0** (within a small epsilon) → pause the element (freeze on the
+  current frame). Reversible by moving the slider off zero. Cancels any reverse
+  loop.
+- **speed < 0** → native negative `playbackRate` is unreliable (Chrome ignores
+  it), so a `requestAnimationFrame` loop owns the element: the element is
+  **paused** and each frame decrements `loopVid.currentTime` by `|speed|·dt`.
+  When it crosses the bottom boundary it **wraps to the tail** (mirror of the
+  forward wrap), reusing the direction-aware landing offset. The loop is
+  cancelled when speed goes ≥ 0, on reduced-motion freeze, when video output is
+  turned off, or when a new loop clip loads.
+
+Interaction with existing motion:
+
+- The manual reverse loop and the **auto-transition tween** (`autoRaf`, which
+  drives the *morph* `#vid`) are independent — different elements, different
+  rAF handles. The reverse loop only owns `#vid-loop`.
+- On landing on a new altitude (`loadLoop` + `playLoop`), the current slider
+  speed is re-applied so the new clip inherits the chosen rate/direction.
+
+## Test seam + tests
+
+Mirrors the existing `scrub.js` / `node --test` pattern:
+
+- A **pure** helper added to `scrub.js`:
+  `reverseStep(t, absSpeed, dt, loopStart, duration) → { next, wrapped }`
+  — computes the next `currentTime` and whether a bottom-boundary wrap occurred.
+  This is the reverse-loop math with no DOM; `app.js` just applies `next` to
+  `loopVid.currentTime`. Covered by a new `node --test` case (steps, wrap at the
+  boundary, clamping).
+- A **Playwright** e2e added to the existing suite: the slider is present;
+  forward value sets `#vid-loop.playbackRate`; `0×` pauses it; a negative value
+  makes `currentTime` decrease over time. Also assert the slider is disabled
+  when `prefers-reduced-motion` is emulated.
+
+## Known risk (noted, not blocking)
+
+Reverse smoothness depends on the **base loop clips'** keyframe density. The
+morphs are all-intra (smooth reverse), but the base altitude clips may not be;
+on some browsers reverse seeking could stutter. The manual loop stays *correct*
+regardless — smoothness is a visual-polish follow-up (re-encode base clips
+all-intra if needed), not a blocker for this change.
+
+## Files touched
+
+- `simulator/static/index.html` — swap toggle → slider + datalist; reword warn.
+- `simulator/static/app.js` — `applyPlaySpeed`, reverse rAF loop, derive
+  `isReduced()` from OS pref, retire `RM_KEY`, re-apply speed on landing.
+- `simulator/static/scrub.js` — add pure `reverseStep` helper.
+- `simulator/static/i18n.js` — add `speed.label`, reword `warn.body` (en/es/fr/ja),
+  retire `rm.label`.
+- `simulator/static/styles.css` — slider styling (reuse audio-level pattern).
+- Tests: `node --test` for `reverseStep`; Playwright e2e for the slider.
+
+## Out of scope
+
+- Re-encoding base clips for smoother reverse (follow-up if stutter is visible).
+- Any speed control over morph/transition videos.
+- Per-altitude or audio speed coupling (audio level is its own control).
diff --git a/sessions/0036/SESSION-0036.0-TRANSCRIPT-2026-06-30T06-30--2026-06-30T12-00.md b/sessions/0036/SESSION-0036.0-TRANSCRIPT-2026-06-30T06-30--2026-06-30T12-00.md
new file mode 100644
index 0000000..9f7b35a
--- /dev/null
+++ b/sessions/0036/SESSION-0036.0-TRANSCRIPT-2026-06-30T06-30--2026-06-30T12-00.md
@@ -0,0 +1,108 @@
+# Session 0036.0 — Transcript
+
+> App: human-experience-filter-art
+> Start: 2026-06-30T06-30 (PST)
+> Type: planning-and-executing
+> Posture: yolo
+> Claude-Session: a7814ad4-473f-4946-b158-a5fad35b4bf1
+> Checkout: /Users/benstull/git/benstull.org/benstull/human-experience-filter-art
+> Status: finalized
+
+## Launch prompt
+
+"Let's publish this to benstull.art. Ideally this would be hosted on Cloudflare
+Pages. Cloudflare Pages does have limits though, so we should check that against
+this project." (Started conversationally — no tracked init; finalized as
+planning-and-executing/yolo.)
+
+## Pre-state
+
+The simulator was a FastAPI server (`simulator/app.py`) serving a ~92 KB static
+frontend + 3.9 GB of media (1080p clip bases + 558 already-720p transition morphs +
+audio) via dynamic endpoints. Not yet public anywhere. Operator wanted it live at
+benstull.art on Cloudflare Pages. Concurrent sessions (0029/0031/0033/0034/0035)
+were active on the SAME checkout.
+
+## Arc
+
+**1. Brainstorm → design → plan (Cloudflare publish).** Established the blocker:
+Pages has a 25 MiB/file hard limit; the project has 26 files >25 MiB. Designed a
+fully-static target: Pages frontend + R2 media (no per-file limit, free egress) +
+read-APIs baked to JSON + client-side pick + `/api/alteration` ported to JS.
+Operator chose: both tiers irrelevant→dropped; path `/human-experience-simulator`
+with apex redirect; no cross-session cache (initially). Spec + plan written under
+`docs/superpowers/`. Operator declared the WHOLE project exempt from flotilla/PPE/§9.
+
+**2. Executed the plan (5 tasks).** Client-side alteration engine (`alteration.js`
++ node/py parity tests); config-driven `mediaBase` + baked-JSON boot + client pick +
+`crossOrigin` for the WebGL dream shader; `tools/build_static.py` (dist/ + manifest-
+only ~2.3 GB media tree + `_redirects`); Cloudflare deploy artifacts; static-build
+E2E. Hit + cleanly extracted a parallel session's in-flight "Run simulation" work
+that got swept into a commit (operator chose extraction).
+
+**3. Live deploy.** Installed wrangler; operator did `wrangler login`. Created R2
+bucket `human-experience-simulator-media`, CORS (wrangler's `{rules:[...]}` schema,
+not S3-style), bound `static.benstull.art` via CLI (zone-id from API), parallel
+604-file upload (no `wrangler r2 sync` exists). Created + deployed Pages project;
+operator bound `benstull.art`. **Live.**
+
+**4. Debugging (systematic).** "Morphs not showing" = upload still in progress
+(transitions sort last) → fixed by parallel upload. "Video + audio not playing" →
+drove the LIVE site with Playwright: video fine, **audio 404'd** because
+`scaleAudioUrl` hardcoded `/media/audio/` instead of `mediaBase()` — fixed.
+"Still no video after hard refresh" → **stale cached JS** (Pages caches .js
+max-age=14400, ignores `_headers`) → fixed with content-versioned asset URLs
+(`app.js?v=<hash>`) + no-cache `_headers`. Private-window confirmed fresh code worked.
+
+**5. Preload algorithm.** "Next altitude's video doesn't start" = a buggy
+hold-last-frame settle gate I'd added (gated playLoop behind a canplay that doesn't
+re-fire) → reverted. Operator specified the algorithm: gate on 1 clip/altitude +
+connecting morphs (~126 MB, ~10-20s — measured), then grow the pool in the
+background; the random pick is restricted to fully-loaded (eligible) clips so
+navigation never stalls and new clips are reachable only once fully downloaded.
+Built `preload.js` (pure planner + node tests), wired phase-1 gate + eligible picks.
+
+**6. Worktree isolation enforcement.** The shared checkout caused branch-switch
+chaos (my commits landed on a switched-to `main`). Operator: "make sure every
+session works off a fresh worktree not in the main directory." Built
+`.claude/settings.json` (worktree.bgIsolation + baseRef:fresh) + a PreToolUse hook
+(`worktree-guard.sh`) that DENIES edits to repo files while in the main checkout +
+SessionStart notice → EnterWorktree. Proven live (blocked my own edit); fixed an
+over-broad version that blocked external files too. Dogfooded the merge of guard +
+preload onto origin/main IN an isolated worktree.
+
+## Cut state
+
+- **Live:** https://benstull.art/human-experience-simulator/ — Pages + R2, preload
+  algorithm, audio fixed, cache-versioned. Operator confirmed video+audio work.
+- **origin/main (`a4d3d83`+):** has the Cloudflare publish, preload algorithm, and
+  worktree-isolation guard, merged cleanly with parallel a11y work.
+- Plan archived in-repo (`docs/superpowers/plans/2026-06-30-cloudflare-static-publish.md`),
+  on origin/main. **No `content` repo** → plan stays in-repo (app.json gap).
+- Local `main` checkout is behind origin/main (parallel session actively deploying).
+- Backup branches on origin: `chore/worktree-isolation`, `fix/preload-gate`,
+  `design/cloudflare-static-publish` (content all merged to main; safe to delete).
+
+## Pipeline (§9) status
+
+Operator-set Cloudflare exception (no flotilla/PPE). localhost + **E2E green** (33
+node tests; 13 altitude-lock + 2 static-build Playwright); no PPE (exempt); **prod =
+live** via `make deploy`. Repeatable deploy: `make deploy` / `make deploy-media`
+(`deploy/cloudflare/`).
+
+## Operator plate (next session)
+
+- By-eye/ear review of the live site: load time, video, audio, rapid-altitude
+  navigation smoothness (eligible-pick growth), the preload behavior under real
+  network. The hold/grow path only triggers when media isn't cached — needs eyes.
+- Restart any still-running sessions so they pick up the worktree guard + move to
+  worktrees. Clean up backup branches if desired.
+
+## Deferred decisions
+
+- Estimated session start time (no tracked init) — used 2026-06-30T06-30.
+- Did NOT reconcile local `main` (behind origin/main) — a parallel session is
+  actively deploying origin/main; left the shared checkout untouched to avoid
+  disrupting it.
+- Cross-session Service-Worker disk cache and a 720p base tier were proposed and
+  DEFERRED (morphs already 720p; bases dominate load but per-altitude growth covers it).
diff --git a/sessions/0037/SESSION-0037.0-TRANSCRIPT-2026-06-30T10-42--2026-06-30T10-52.md b/sessions/0037/SESSION-0037.0-TRANSCRIPT-2026-06-30T10-42--2026-06-30T10-52.md
new file mode 100644
index 0000000..ce76dca
--- /dev/null
+++ b/sessions/0037/SESSION-0037.0-TRANSCRIPT-2026-06-30T10-42--2026-06-30T10-52.md
@@ -0,0 +1,76 @@
+# Session 0037.0 — Transcript
+
+> App: human-experience-filter-art
+> Start: 2026-06-30T10-42 (PST)
+> Type: planning-and-executing
+> Posture: yolo
+> Claude-Session: aa7ac424-d797-4918-8837-2a904441d91e
+> Checkout: /Users/benstull/git/benstull.org/benstull/human-experience-filter-art/.claude/worktrees/session-0037-altitude-snap-on-release
+> End: 2026-06-30T10-52 (PST)
+> Status: **FINALIZED.**
+
+## Summary
+
+Single-task UX session. Made the altitude dial **snap to the closest altitude on
+drag release** so a grab-and-release always lands on a discrete altitude, just
+like a tap/label-click.
+
+### Arc
+
+1. Claimed session 0037 (two stale `--INPROGRESS` placeholders 0015/0017 noted,
+   not live). Worked in an isolated worktree
+   (`session-0037-altitude-snap-on-release`) branched off `origin/main` (local
+   `main` was 7 behind).
+2. Located the behavior: `onDialUp` (`simulator/static/app.js`) held the live
+   blend wherever a real turn stopped — the "no auto-complete" continuous-encoder
+   model. Tap path (`moved < 6` → `jumpToScale`) and wheel/label auto-scrub were
+   already snap-to-altitude.
+3. TDD: added an `altitude-lock.spec.ts` e2e ("releasing a partial drag snaps to
+   the closest altitude") — confirmed RED (held pos never became integer).
+4. Implemented: a real turn (`moved >= 6`) now `autoScrub(Math.round(pos))` →
+   short scrub to the nearest altitude, settle + lock (frac 0). Reduced motion is
+   handled inside `autoScrub` (jump-to-target). GREEN.
+5. Verified: full altitude-lock (14) + a11y + i18n e2e suites green. Committed,
+   pushed, opened PR #31, merged to `main` (`5696b94`).
+
+### Pipeline (§9)
+
+This app is **exempt** from flotilla/PPE/§9 prod gate — public target is static
+Cloudflare (Pages + R2). Change is merged to `main`; **operator redeploy** of the
+static build is the remaining ship step. No plan artifact archived: the change
+was a trivial leaf `task`, planned inline (no separate plan file; app has no
+content repo).
+
+### Next session
+
+Operator by-eye review of the snap feel on the live sim, then redeploy to
+Cloudflare.
+
+## Launch prompt
+
+> When the user is dragging the slider (rather than clicking on an altitude),
+> let's transition to the closest altitude when they let go. That way, the user
+> will always land on an altitude as if they clicked one, even if they're
+> grabbing and releasing the slider.
+
+## Plan
+
+> Anchor: leaf `task` (UX behavior tweak — directly plan-eligible, R2b).
+
+Snap-on-release for the altitude dial. Today `onDialUp` (app.js) holds the live
+blend wherever a drag stops (the "no auto-complete" continuous-encoder model).
+Change: after a real turn (`moved >= 6`), `autoScrub(Math.round(pos))` so the
+knob settles on the CLOSEST altitude (frac 0 → lock), identical to a tap/click.
+Tap path (`moved < 6` → `jumpToScale`) unchanged. Reduced-motion is handled by
+`autoScrub` (jump-to-target, no tween).
+
+Verification: new e2e in `altitude-lock.spec.ts` ("releasing a partial drag
+snaps to the closest altitude") — TDD red→green; full altitude-lock (14) + a11y
++ i18n suites green. Project is exempt from §9/PPE (static Cloudflare target);
+ships branch → PR → merge → operator redeploy.
+
+## Deferred decisions
+
+_Autonomous-mode low-confidence calls the driver made and would have
+liked operator input on. Appended as the session runs; surfaced at
+finalize. Empty if none._
diff --git a/sessions/sessions.json b/sessions/sessions.json
index 93fe965..50d5654 100644
--- a/sessions/sessions.json
+++ b/sessions/sessions.json
@@ -103,5 +103,11 @@
   },
   "0035": {
     "title": ""
+  },
+  "0036": {
+    "title": ""
+  },
+  "0037": {
+    "title": ""
   }
 }
diff --git a/simulator/e2e/test-results/.last-run.json b/simulator/e2e/test-results/.last-run.json
deleted file mode 100644
index cbcc1fb..0000000
--- a/simulator/e2e/test-results/.last-run.json
+++ /dev/null
@@ -1,4 +0,0 @@
-{
-  "status": "passed",
-  "failedTests": []
-}
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-1-—-Output-panel-36682-its-below-the-Audio-control/error-context.md b/simulator/e2e/test-results/a11y-Task-1-—-Output-panel-36682-its-below-the-Audio-control/error-context.md
new file mode 100644
index 0000000..92c12c7
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-1-—-Output-panel-36682-its-below-the-Audio-control/error-context.md
@@ -0,0 +1,137 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 1 — Output panel layout >> language picker sits below the Audio control
+- Location: tests/a11y.spec.ts:15:7
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [ref=e2]: "{\"detail\":\"Not Found\"}"
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+> 9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+  43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-1-—-Output-panel-4e222-e-language-select-same-row-/error-context.md b/simulator/e2e/test-results/a11y-Task-1-—-Output-panel-4e222-e-language-select-same-row-/error-context.md
new file mode 100644
index 0000000..8bfa68d
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-1-—-Output-panel-4e222-e-language-select-same-row-/error-context.md
@@ -0,0 +1,202 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 1 — Output panel layout >> globe icon is inline-left of the language select (same row)
+- Location: tests/a11y.spec.ts:27:7
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode"
+        - generic [ref=e69]: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+> 9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+  43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-4-—-Photosensiti-eae44-otice-and-the-Speed-control/error-context.md b/simulator/e2e/test-results/a11y-Task-4-—-Photosensiti-eae44-otice-and-the-Speed-control/error-context.md
new file mode 100644
index 0000000..861139d
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-4-—-Photosensiti-eae44-otice-and-the-Speed-control/error-context.md
@@ -0,0 +1,226 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 4 — Photosensitivity notice >> the welcome screen carries the heads-up notice and the Speed control
+- Location: tests/a11y.spec.ts:40:7
+
+# Error details
+
+```
+Error: expect(locator).toBeVisible() failed
+
+Locator: locator('#welcome-title')
+Expected: visible
+Timeout: 5000ms
+Error: element(s) not found
+
+Call log:
+  - Expect "toBeVisible" with timeout 5000ms
+  - waiting for locator('#welcome-title')
+
+```
+
+```yaml
+- banner:
+  - heading "Human Experience Filter — Alteration Preview" [level=1]
+  - link "About":
+    - /url: about.html
+  - link "ⓘ Credits & licenses":
+    - /url: credits.html
+- main:
+  - button "Run simulation"
+  - dialog "Heads up — motion & flashing":
+    - heading "Heads up — motion & flashing" [level=2]
+    - paragraph: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+    - button "Continue"
+  - status: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+  - group "Output":
+    - text: Output
+    - checkbox "Video"
+    - text: Video Audio
+    - slider "Audio 0 /10": "0"
+    - text: 0 /10 Speed
+    - slider "Speed 1.00×": "1"
+    - text: 1.00× 🌐
+    - combobox "Language":
+      - option "English" [selected]
+      - option "Español"
+      - option "Français"
+      - option "日本語"
+  - group "Altitude":
+    - text: Altitude
+    - slider "Altitude — turn or use arrow keys to change scale":
+      - button "cosmos"
+      - button "orbit"
+      - button "sky"
+      - button "coast"
+      - button "reef"
+      - button "abyss"
+      - text: ALTITUDE
+    - text: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+    - paragraph: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+  - group "Experience knobs (0–4)":
+    - text: Experience knobs (0–4) Think
+    - slider "Think": "0"
+    - text: Feel
+    - slider "Feel": "0"
+    - text: Mood — dark ◀ 0 ▶ light
+    - slider "Mood — dark ◀ 0 ▶ light": "0"
+  - checkbox "Dev Mode"
+  - text: Dev Mode
+- text: ⬇ caching clips 363/599
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+  9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+> 43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+      |                                                  ^ Error: expect(locator).toBeVisible() failed
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+  110 | test.describe("Task 6 — Keyboard + ARIA dial", () => {
+  111 |   test("altitude dial is a keyboard-operable slider", async ({ page }) => {
+  112 |     await page.goto("/");
+  113 |     await enter(page);
+  114 |     const dial = page.locator("#dial");
+  115 |     await expect(dial).toHaveAttribute("role", "slider");
+  116 |     await expect(dial).toHaveAttribute("tabindex", "0");
+  117 |     await dial.focus();
+  118 |     const before = await page.locator("#scale-name").textContent();
+  119 |     await dial.press("ArrowDown");               // descend one altitude
+  120 |     await expect
+  121 |       .poll(async () => page.locator("#scale-name").textContent())
+  122 |       .not.toBe(before);
+  123 |     await dial.press("Home");                    // jump to the top scale (cosmos)
+  124 |     await expect(page.locator("#scale-name")).toHaveText(/cosmos|宇宙/i);
+  125 |     await expect(dial).toHaveAttribute("aria-valuenow", "0");
+  126 |   });
+  127 | });
+  128 | 
+  129 | test.describe("Task 7 — Screen-reader narration", () => {
+  130 |   test("an aria-live region narrates the current scale", async ({ page }) => {
+  131 |     await page.goto("/");
+  132 |     await enter(page);
+  133 |     const live = page.locator("#sr-status");
+  134 |     await expect(live).toHaveAttribute("aria-live", "polite");
+  135 |     await page.locator("#dial").focus();
+  136 |     await page.locator("#dial").press("Home");
+  137 |     await expect
+  138 |       .poll(async () => (await live.textContent())?.toLowerCase())
+  139 |       .toContain("cosmos");
+  140 |   });
+  141 | 
+  142 |   test("decorative overlay SVGs are hidden from assistive tech", async ({ page }) => {
+  143 |     await page.goto("/");
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-509d1-e-loop-video-s-playbackRate/error-context.md b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-509d1-e-loop-video-s-playbackRate/error-context.md
new file mode 100644
index 0000000..1c767f1
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-509d1-e-loop-video-s-playbackRate/error-context.md
@@ -0,0 +1,202 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 5 — Playback speed slider (replaces Reduce motion) >> forward speed sets the loop video's playbackRate
+- Location: tests/a11y.spec.ts:62:7
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode"
+        - generic [ref=e69]: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+> 9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+  43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-78ef6-slider-and-freezes-the-loop/error-context.md b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-78ef6-slider-and-freezes-the-loop/error-context.md
new file mode 100644
index 0000000..b6de8e4
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-78ef6-slider-and-freezes-the-loop/error-context.md
@@ -0,0 +1,206 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 5 — Playback speed slider (replaces Reduce motion) >> OS reduced-motion disables the slider and freezes the loop
+- Location: tests/a11y.spec.ts:99:7
+
+# Error details
+
+```
+Error: Channel closed
+```
+
+```
+Error: page.waitForFunction: Test ended.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [disabled] [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode"
+        - generic [ref=e69]: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+> 9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ Error: page.waitForFunction: Test ended.
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+  43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-7f910-n-0x-freezes-the-loop-video/error-context.md b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-7f910-n-0x-freezes-the-loop-video/error-context.md
new file mode 100644
index 0000000..84569fd
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-7f910-n-0x-freezes-the-loop-video/error-context.md
@@ -0,0 +1,202 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 5 — Playback speed slider (replaces Reduce motion) >> 0x freezes the loop video
+- Location: tests/a11y.spec.ts:72:7
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode"
+        - generic [ref=e69]: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+> 9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+  43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-d97a0-erse-manual-frame-stepping-/error-context.md b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-d97a0-erse-manual-frame-stepping-/error-context.md
new file mode 100644
index 0000000..e8a80f8
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-d97a0-erse-manual-frame-stepping-/error-context.md
@@ -0,0 +1,202 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 5 — Playback speed slider (replaces Reduce motion) >> negative speed plays the loop in reverse (manual frame-stepping)
+- Location: tests/a11y.spec.ts:82:7
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode"
+        - generic [ref=e69]: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+> 9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+  43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-f4262--replaced-by-a-speed-slider/error-context.md b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-f4262--replaced-by-a-speed-slider/error-context.md
new file mode 100644
index 0000000..c0ddf1d
--- /dev/null
+++ b/simulator/e2e/test-results/a11y-Task-5-—-Playback-spe-f4262--replaced-by-a-speed-slider/error-context.md
@@ -0,0 +1,202 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: a11y.spec.ts >> Task 5 — Playback speed slider (replaces Reduce motion) >> the Reduce motion toggle is gone, replaced by a speed slider
+- Location: tests/a11y.spec.ts:52:7
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode"
+        - generic [ref=e69]: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // Accessibility pass (feat/accessibility-pass) — non-kiosk public-web a11y.
+  4   | // Each block maps to a task in
+  5   | // docs/superpowers/plans/2026-06-30-accessibility-and-about-page.md.
+  6   | 
+  7   | // Enter the simulation via the welcome screen (the panel is hidden until then).
+  8   | async function enter(page: Page) {
+> 9   |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  10  |   await page.locator("#welcome-launch").click();
+  11  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  12  | }
+  13  | 
+  14  | test.describe("Task 1 — Output panel layout", () => {
+  15  |   test("language picker sits below the Audio control", async ({ page }) => {
+  16  |     await page.goto("/");
+  17  |     await enter(page);
+  18  |     const audio = page.locator("#audio");
+  19  |     const lang = page.locator("#lang-select");
+  20  |     await expect(audio).toBeVisible();
+  21  |     await expect(lang).toBeVisible();
+  22  |     const aBox = await audio.boundingBox();
+  23  |     const lBox = await lang.boundingBox();
+  24  |     expect(lBox!.y).toBeGreaterThan(aBox!.y); // lang renders lower than audio
+  25  |   });
+  26  | 
+  27  |   test("globe icon is inline-left of the language select (same row)", async ({ page }) => {
+  28  |     await page.goto("/");
+  29  |     await enter(page);
+  30  |     const pick = page.locator(".panel .lang-pick");
+  31  |     const select = page.locator("#lang-select");
+  32  |     const pBox = await pick.boundingBox();
+  33  |     const sBox = await select.boundingBox();
+  34  |     expect(sBox!.x).toBeGreaterThan(pBox!.x); // select right of the label's left edge
+  35  |     expect(pBox!.height).toBeLessThan(40);    // one row, not stacked
+  36  |   });
+  37  | });
+  38  | 
+  39  | test.describe("Task 4 — Photosensitivity notice", () => {
+  40  |   test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
+  41  |     await page.goto("/");
+  42  |     // The heads-up is shown on the welcome screen itself (it is the entry gate).
+  43  |     await expect(page.locator("#welcome-title")).toBeVisible();
+  44  |     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
+  45  |     // The Speed control + Launch button sit right there, before the visitor launches.
+  46  |     await expect(page.locator("#welcome-play-speed")).toBeVisible();
+  47  |     await expect(page.locator("#welcome-launch")).toBeVisible();
+  48  |   });
+  49  | });
+  50  | 
+  51  | test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  52  |   test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+  53  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  54  |     await page.goto("/");
+  55  |     await enter(page);
+  56  |     await expect(page.locator("#reduce-motion")).toHaveCount(0);
+  57  |     const slider = page.locator("#play-speed");
+  58  |     await expect(slider).toBeVisible();
+  59  |     await expect(slider).toHaveValue("1");        // default = normal speed
+  60  |   });
+  61  | 
+  62  |   test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+  63  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  64  |     await page.goto("/");
+  65  |     await enter(page);
+  66  |     await page.locator("#play-speed").fill("2");
+  67  |     await expect
+  68  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+  69  |       .toBe(2);
+  70  |   });
+  71  | 
+  72  |   test("0x freezes the loop video", async ({ page }) => {
+  73  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  74  |     await page.goto("/");
+  75  |     await enter(page);
+  76  |     await page.locator("#play-speed").fill("0");
+  77  |     await expect
+  78  |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  79  |       .toBe(true);
+  80  |   });
+  81  | 
+  82  |   test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+  83  |     await page.emulateMedia({ reducedMotion: "no-preference" });
+  84  |     await page.goto("/");
+  85  |     await enter(page);
+  86  |     await page.locator("#play-speed").fill("-1.5");
+  87  |     await page.waitForTimeout(150);
+  88  |     const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  89  |     const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+  90  |     await page.waitForTimeout(250);
+  91  |     const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+  92  |     // The reverse loop pauses the element and drives currentTime by hand — so the
+  93  |     // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+  94  |     // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+  95  |     expect(paused).toBe(true);
+  96  |     expect(b).not.toBe(a);
+  97  |   });
+  98  | 
+  99  |   test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+  100 |     await page.emulateMedia({ reducedMotion: "reduce" });
+  101 |     await page.goto("/");
+  102 |     await enter(page);
+  103 |     await expect(page.locator("#play-speed")).toBeDisabled();
+  104 |     await expect
+  105 |       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
+  106 |       .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
+  107 |   });
+  108 | });
+  109 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/altitude-lock-a-landed-cli-4f073-et-no-jump-back-to-frame-0-/error-context.md b/simulator/e2e/test-results/altitude-lock-a-landed-cli-4f073-et-no-jump-back-to-frame-0-/error-context.md
new file mode 100644
index 0000000..bf7473a
--- /dev/null
+++ b/simulator/e2e/test-results/altitude-lock-a-landed-cli-4f073-et-no-jump-back-to-frame-0-/error-context.md
@@ -0,0 +1,271 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: altitude-lock.spec.ts >> a landed clip loops from the morph-tail offset (no jump-back to frame 0)
+- Location: tests/altitude-lock.spec.ts:137:5
+
+# Error details
+
+```
+Error: Channel closed
+```
+
+```
+Error: page.waitForFunction: Test ended.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode" [checked]
+        - generic [ref=e69]: Dev Mode
+      - generic [ref=e70]:
+        - group "Audio diagnostics" [ref=e71]:
+          - generic [ref=e72]: Audio diagnostics
+          - generic [ref=e73]: "audio: off (level 0)"
+          - paragraph [ref=e74]: Native player — tests the soundtrack file directly (bypasses all app code). If it plays here but the Audio toggle is silent, it's a code/autoplay issue, not the file.
+        - group "Pool — pick a clip" [ref=e76]:
+          - generic [ref=e77]: Pool — pick a clip
+          - combobox "Choose a clip from this altitude's pool" [ref=e78]:
+            - option "cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)" [selected]
+            - option "cosmos_galaxies · Flying Through Galaxies (NASA SVS)"
+            - option "cosmos_orion · Orion Nebula — visible/IR flythrough (NASA SVS)"
+            - option "cosmos_tarantula · Tarantula Nebula (30 Doradus) zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_westerlund · Flight through star cluster Westerlund 2 (ESA/Hubble)"
+            - option "cosmos_southernring · Southern Ring Nebula zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_carina_eso · Carina Nebula zoom (ESO)"
+          - button "🎲 Re-roll random" [ref=e79] [cursor=pointer]
+        - group "Active clip" [ref=e80]:
+          - generic [ref=e81]: Active clip
+          - generic [ref=e82]:
+            - term [ref=e83]: id
+            - definition [ref=e84]: cosmos
+            - term [ref=e85]: title
+            - definition [ref=e86]: Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+            - term [ref=e87]: source
+            - definition [ref=e88]: NASA SVS 31348 Clifs-3d-STScI (Exploring the Cosmic Cliffs in 3D, Webb NIRCam); 4K source, trim 10–34s, crossfade-loop. Text-free — replaces the Orion SVS 30957 flythrough.
+            - term [ref=e89]: license
+            - definition [ref=e90]: CC-BY-class — credit NASA, ESA, CSA, STScI
+            - term [ref=e91]: base_file
+            - definition [ref=e92]: cosmos/base.mp4
+        - group "Annotations & affect" [ref=e93]:
+          - generic [ref=e94]: Annotations & affect
+          - generic [ref=e95]:
+            - generic [ref=e96]: detected.nebula · sal 4 · 4 tiers
+            - generic [ref=e97]: detected.star · sal 2 · 4 tiers
+            - generic [ref=e98]: measure.distance · min L3 · 1 tier
+            - generic [ref=e99]: feel.wonder · min L1 · 4 tiers
+            - generic [ref=e100]: feel.sublime · min L2 · 4 tiers
+            - generic [ref=e101]: feel.vastness · min L3 · 4 tiers
+            - generic [ref=e102]: feel.insignificance · min L4 · 4 tiers
+        - group "RenderPlan" [ref=e103]:
+          - generic [ref=e104]: RenderPlan
+          - generic [ref=e105]: "{ \"plan\": { \"grade\": { \"tone\": 0 }, \"overlay\": { \"level\": 0, \"intensity\": 0 }, \"affect\": { \"strength\": 0, \"intensity\": 0 }, \"dream\": { \"strength\": 0, \"intensity\": 0 }, \"is_identity\": true }, \"render\": { \"video\": { \"shown\": false }, \"audio\": { \"source\": \"off\", \"url\": null, \"altitude_coupled\": false } } }"
+        - group "Cache & playback" [ref=e106]:
+          - generic [ref=e107]: Cache & playback
+          - generic [ref=e108]:
+            - term [ref=e109]: cache
+            - definition [ref=e110]: 496/41 cached
+            - term [ref=e111]: active source
+            - definition [ref=e112]: memory (blob)
+            - term [ref=e113]: resolution
+            - definition [ref=e114]: —
+            - term [ref=e115]: duration
+            - definition [ref=e116]: —
+            - term [ref=e117]: loop pos
+            - definition [ref=e118]: —
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // These assert the two behaviors the operator asked for:
+  4   | //   1. zooming plays the morph matching the clip we land on, and
+  5   | //   2. after landing the clip is LOCKED — it does not change while parked.
+  6   | //
+  7   | // The played morph paths are read from window.__hefMorphs (a diagnostic seam in
+  8   | // advance()), which is reliable even when the morph is served from an in-memory
+  9   | // blob cache. The locked clip is read from the Dev-Mode "#scale-name" readout
+  10  | // ("<scale> · <clip>  (i/n)").
+  11  | 
+  12  | async function boot(page: Page) {
+  13  |   await page.addInitScript(() => {
+  14  |     localStorage.setItem("hef.devMode", "1");
+  15  |   });
+  16  |   await page.goto("/");
+  17  |   // Wait for phase-1 preload, then enter via the welcome screen's Launch button
+  18  |   // (Video defaults on, Audio 2 → the experience is running once we're in).
+> 19  |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ Error: page.waitForFunction: Test ended.
+  20  |   await page.locator("#welcome-launch").click();
+  21  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  22  |   await expect(page.locator("#scale-name")).toContainText("cosmos");
+  23  | }
+  24  | 
+  25  | async function morphs(page: Page): Promise<string[]> {
+  26  |   return await page.evaluate(() => (window as any).__hefMorphs || []);
+  27  | }
+  28  | 
+  29  | async function wheelOnStage(page: Page, deltaY: number) {
+  30  |   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
+  31  | }
+  32  | 
+  33  | // The Audio control is a 0–10 level slider; set it to full + fire `input` directly
+  34  | // (headless Chromium relaxes the autoplay gesture requirement).
+  35  | async function enableAudio(page: Page) {
+  36  |   await page.evaluate(() => {
+  37  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  38  |     c.value = "10";
+  39  |     c.dispatchEvent(new Event("input", { bubbles: true }));
+  40  |   });
+  41  | }
+  42  | 
+  43  | // The Video toggle gates the base-clip loop (update() only loads media when video is
+  44  | // shown). Same hidden-checkbox pattern.
+  45  | async function enableVideo(page: Page) {
+  46  |   await page.evaluate(() => {
+  47  |     const c = document.querySelector("#visual") as HTMLInputElement;
+  48  |     c.checked = true;
+  49  |     c.dispatchEvent(new Event("change", { bubbles: true }));
+  50  |   });
+  51  | }
+  52  | 
+  53  | test("two audio elements exist for crossfade", async ({ page }) => {
+  54  |   await boot(page);
+  55  |   const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  56  |   expect(n).toBe(2);
+  57  | });
+  58  | 
+  59  | test("a new volume fade supersedes a stale one (audio not silenced after landing)", async ({ page }) => {
+  60  |   await boot(page);
+  61  |   // Reproduce the race: a fade-to-0 in flight, then the same element is brought back
+  62  |   // up (as happens when a faded idle element becomes the newly-landed active scale).
+  63  |   // The stale fade must NOT drag it back to 0.
+  64  |   const vol = await page.evaluate(async () => {
+  65  |     const a = document.querySelector("#aud") as HTMLAudioElement;
+  66  |     a.volume = 1;
+  67  |     (window as any).__hefFade(a, 0, 600);              // start a slow fade to 0
+  68  |     await new Promise((r) => setTimeout(r, 120));      // let it ramp partway down
+  69  |     (window as any).__hefFade(a, 0.8, 90);             // new fade up — must cancel the old one
+  70  |     await new Promise((r) => setTimeout(r, 350));      // well past both fades
+  71  |     return a.volume;
+  72  |   });
+  73  |   expect(vol).toBeGreaterThan(0.7);                    // ended near 0.8, not dragged to 0
+  74  | });
+  75  | 
+  76  | test("audio is a 0-10 level dial", async ({ page }) => {
+  77  |   await boot(page);
+  78  |   const ctl = await page.evaluate(() => {
+  79  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  80  |     return { type: c.type, min: c.min, max: c.max };
+  81  |   });
+  82  |   expect(ctl.type).toBe("range");
+  83  |   expect(ctl.min).toBe("0");
+  84  |   expect(ctl.max).toBe("10");
+  85  | });
+  86  | 
+  87  | // (Entry via the welcome screen — defaults, Launch, control carry-over, State B —
+  88  | // is covered in welcome.spec.ts.)
+  89  | 
+  90  | test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  91  |   await boot(page);
+  92  |   await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  93  |   const box = (await page.locator("#dial").boundingBox())!;
+  94  |   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  95  |   await page.mouse.move(cx, cy - 30);
+  96  |   await page.mouse.down();
+  97  |   await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  98  |   // The currentTime seek is throttled to one rAF; wait for it to land.
+  99  |   await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  100 |   const state = await page.evaluate(() => ({
+  101 |     t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+  102 |     ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+  103 |     gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  104 |   }));
+  105 |   expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  106 |   expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  107 |   expect(state.ga).toBeLessThan(1);            // current scale fading out
+  108 |   await page.mouse.up();
+  109 | });
+  110 | 
+  111 | test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  112 |   await boot(page);
+  113 |   const start = (await page.locator("#scale-name").textContent())!;
+  114 |   await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  115 |   await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  116 |   const landed = (await page.locator("#scale-name").textContent())!;
+  117 |   expect(landed).toContain("orbit");
+  118 |   await page.waitForTimeout(1500);
+  119 |   expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/altitude-lock-a-new-volume-6541e-not-silenced-after-landing-/error-context.md b/simulator/e2e/test-results/altitude-lock-a-new-volume-6541e-not-silenced-after-landing-/error-context.md
new file mode 100644
index 0000000..4c28318
--- /dev/null
+++ b/simulator/e2e/test-results/altitude-lock-a-new-volume-6541e-not-silenced-after-landing-/error-context.md
@@ -0,0 +1,267 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: altitude-lock.spec.ts >> a new volume fade supersedes a stale one (audio not silenced after landing)
+- Location: tests/altitude-lock.spec.ts:59:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode" [checked]
+        - generic [ref=e69]: Dev Mode
+      - generic [ref=e70]:
+        - group "Audio diagnostics" [ref=e71]:
+          - generic [ref=e72]: Audio diagnostics
+          - generic [ref=e73]: "audio: off (level 0)"
+          - paragraph [ref=e74]: Native player — tests the soundtrack file directly (bypasses all app code). If it plays here but the Audio toggle is silent, it's a code/autoplay issue, not the file.
+        - group "Pool — pick a clip" [ref=e76]:
+          - generic [ref=e77]: Pool — pick a clip
+          - combobox "Choose a clip from this altitude's pool" [ref=e78]:
+            - option "cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)" [selected]
+            - option "cosmos_galaxies · Flying Through Galaxies (NASA SVS)"
+            - option "cosmos_orion · Orion Nebula — visible/IR flythrough (NASA SVS)"
+            - option "cosmos_tarantula · Tarantula Nebula (30 Doradus) zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_westerlund · Flight through star cluster Westerlund 2 (ESA/Hubble)"
+            - option "cosmos_southernring · Southern Ring Nebula zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_carina_eso · Carina Nebula zoom (ESO)"
+          - button "🎲 Re-roll random" [ref=e79] [cursor=pointer]
+        - group "Active clip" [ref=e80]:
+          - generic [ref=e81]: Active clip
+          - generic [ref=e82]:
+            - term [ref=e83]: id
+            - definition [ref=e84]: cosmos
+            - term [ref=e85]: title
+            - definition [ref=e86]: Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+            - term [ref=e87]: source
+            - definition [ref=e88]: NASA SVS 31348 Clifs-3d-STScI (Exploring the Cosmic Cliffs in 3D, Webb NIRCam); 4K source, trim 10–34s, crossfade-loop. Text-free — replaces the Orion SVS 30957 flythrough.
+            - term [ref=e89]: license
+            - definition [ref=e90]: CC-BY-class — credit NASA, ESA, CSA, STScI
+            - term [ref=e91]: base_file
+            - definition [ref=e92]: cosmos/base.mp4
+        - group "Annotations & affect" [ref=e93]:
+          - generic [ref=e94]: Annotations & affect
+          - generic [ref=e95]:
+            - generic [ref=e96]: detected.nebula · sal 4 · 4 tiers
+            - generic [ref=e97]: detected.star · sal 2 · 4 tiers
+            - generic [ref=e98]: measure.distance · min L3 · 1 tier
+            - generic [ref=e99]: feel.wonder · min L1 · 4 tiers
+            - generic [ref=e100]: feel.sublime · min L2 · 4 tiers
+            - generic [ref=e101]: feel.vastness · min L3 · 4 tiers
+            - generic [ref=e102]: feel.insignificance · min L4 · 4 tiers
+        - group "RenderPlan" [ref=e103]:
+          - generic [ref=e104]: RenderPlan
+          - generic [ref=e105]: "{ \"plan\": { \"grade\": { \"tone\": 0 }, \"overlay\": { \"level\": 0, \"intensity\": 0 }, \"affect\": { \"strength\": 0, \"intensity\": 0 }, \"dream\": { \"strength\": 0, \"intensity\": 0 }, \"is_identity\": true }, \"render\": { \"video\": { \"shown\": false }, \"audio\": { \"source\": \"off\", \"url\": null, \"altitude_coupled\": false } } }"
+        - group "Cache & playback" [ref=e106]:
+          - generic [ref=e107]: Cache & playback
+          - generic [ref=e108]:
+            - term [ref=e109]: cache
+            - definition [ref=e110]: 497/41 cached
+            - term [ref=e111]: active source
+            - definition [ref=e112]: memory (blob)
+            - term [ref=e113]: resolution
+            - definition [ref=e114]: —
+            - term [ref=e115]: duration
+            - definition [ref=e116]: —
+            - term [ref=e117]: loop pos
+            - definition [ref=e118]: —
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // These assert the two behaviors the operator asked for:
+  4   | //   1. zooming plays the morph matching the clip we land on, and
+  5   | //   2. after landing the clip is LOCKED — it does not change while parked.
+  6   | //
+  7   | // The played morph paths are read from window.__hefMorphs (a diagnostic seam in
+  8   | // advance()), which is reliable even when the morph is served from an in-memory
+  9   | // blob cache. The locked clip is read from the Dev-Mode "#scale-name" readout
+  10  | // ("<scale> · <clip>  (i/n)").
+  11  | 
+  12  | async function boot(page: Page) {
+  13  |   await page.addInitScript(() => {
+  14  |     localStorage.setItem("hef.devMode", "1");
+  15  |   });
+  16  |   await page.goto("/");
+  17  |   // Wait for phase-1 preload, then enter via the welcome screen's Launch button
+  18  |   // (Video defaults on, Audio 2 → the experience is running once we're in).
+> 19  |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  20  |   await page.locator("#welcome-launch").click();
+  21  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  22  |   await expect(page.locator("#scale-name")).toContainText("cosmos");
+  23  | }
+  24  | 
+  25  | async function morphs(page: Page): Promise<string[]> {
+  26  |   return await page.evaluate(() => (window as any).__hefMorphs || []);
+  27  | }
+  28  | 
+  29  | async function wheelOnStage(page: Page, deltaY: number) {
+  30  |   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
+  31  | }
+  32  | 
+  33  | // The Audio control is a 0–10 level slider; set it to full + fire `input` directly
+  34  | // (headless Chromium relaxes the autoplay gesture requirement).
+  35  | async function enableAudio(page: Page) {
+  36  |   await page.evaluate(() => {
+  37  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  38  |     c.value = "10";
+  39  |     c.dispatchEvent(new Event("input", { bubbles: true }));
+  40  |   });
+  41  | }
+  42  | 
+  43  | // The Video toggle gates the base-clip loop (update() only loads media when video is
+  44  | // shown). Same hidden-checkbox pattern.
+  45  | async function enableVideo(page: Page) {
+  46  |   await page.evaluate(() => {
+  47  |     const c = document.querySelector("#visual") as HTMLInputElement;
+  48  |     c.checked = true;
+  49  |     c.dispatchEvent(new Event("change", { bubbles: true }));
+  50  |   });
+  51  | }
+  52  | 
+  53  | test("two audio elements exist for crossfade", async ({ page }) => {
+  54  |   await boot(page);
+  55  |   const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  56  |   expect(n).toBe(2);
+  57  | });
+  58  | 
+  59  | test("a new volume fade supersedes a stale one (audio not silenced after landing)", async ({ page }) => {
+  60  |   await boot(page);
+  61  |   // Reproduce the race: a fade-to-0 in flight, then the same element is brought back
+  62  |   // up (as happens when a faded idle element becomes the newly-landed active scale).
+  63  |   // The stale fade must NOT drag it back to 0.
+  64  |   const vol = await page.evaluate(async () => {
+  65  |     const a = document.querySelector("#aud") as HTMLAudioElement;
+  66  |     a.volume = 1;
+  67  |     (window as any).__hefFade(a, 0, 600);              // start a slow fade to 0
+  68  |     await new Promise((r) => setTimeout(r, 120));      // let it ramp partway down
+  69  |     (window as any).__hefFade(a, 0.8, 90);             // new fade up — must cancel the old one
+  70  |     await new Promise((r) => setTimeout(r, 350));      // well past both fades
+  71  |     return a.volume;
+  72  |   });
+  73  |   expect(vol).toBeGreaterThan(0.7);                    // ended near 0.8, not dragged to 0
+  74  | });
+  75  | 
+  76  | test("audio is a 0-10 level dial", async ({ page }) => {
+  77  |   await boot(page);
+  78  |   const ctl = await page.evaluate(() => {
+  79  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  80  |     return { type: c.type, min: c.min, max: c.max };
+  81  |   });
+  82  |   expect(ctl.type).toBe("range");
+  83  |   expect(ctl.min).toBe("0");
+  84  |   expect(ctl.max).toBe("10");
+  85  | });
+  86  | 
+  87  | // (Entry via the welcome screen — defaults, Launch, control carry-over, State B —
+  88  | // is covered in welcome.spec.ts.)
+  89  | 
+  90  | test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  91  |   await boot(page);
+  92  |   await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  93  |   const box = (await page.locator("#dial").boundingBox())!;
+  94  |   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  95  |   await page.mouse.move(cx, cy - 30);
+  96  |   await page.mouse.down();
+  97  |   await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  98  |   // The currentTime seek is throttled to one rAF; wait for it to land.
+  99  |   await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  100 |   const state = await page.evaluate(() => ({
+  101 |     t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+  102 |     ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+  103 |     gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  104 |   }));
+  105 |   expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  106 |   expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  107 |   expect(state.ga).toBeLessThan(1);            // current scale fading out
+  108 |   await page.mouse.up();
+  109 | });
+  110 | 
+  111 | test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  112 |   await boot(page);
+  113 |   const start = (await page.locator("#scale-name").textContent())!;
+  114 |   await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  115 |   await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  116 |   const landed = (await page.locator("#scale-name").textContent())!;
+  117 |   expect(landed).toContain("orbit");
+  118 |   await page.waitForTimeout(1500);
+  119 |   expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/altitude-lock-audio-is-a-0-10-level-dial/error-context.md b/simulator/e2e/test-results/altitude-lock-audio-is-a-0-10-level-dial/error-context.md
new file mode 100644
index 0000000..5021f90
--- /dev/null
+++ b/simulator/e2e/test-results/altitude-lock-audio-is-a-0-10-level-dial/error-context.md
@@ -0,0 +1,267 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: altitude-lock.spec.ts >> audio is a 0-10 level dial
+- Location: tests/altitude-lock.spec.ts:76:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode" [checked]
+        - generic [ref=e69]: Dev Mode
+      - generic [ref=e70]:
+        - group "Audio diagnostics" [ref=e71]:
+          - generic [ref=e72]: Audio diagnostics
+          - generic [ref=e73]: "audio: off (level 0)"
+          - paragraph [ref=e74]: Native player — tests the soundtrack file directly (bypasses all app code). If it plays here but the Audio toggle is silent, it's a code/autoplay issue, not the file.
+        - group "Pool — pick a clip" [ref=e76]:
+          - generic [ref=e77]: Pool — pick a clip
+          - combobox "Choose a clip from this altitude's pool" [ref=e78]:
+            - option "cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)" [selected]
+            - option "cosmos_galaxies · Flying Through Galaxies (NASA SVS)"
+            - option "cosmos_orion · Orion Nebula — visible/IR flythrough (NASA SVS)"
+            - option "cosmos_tarantula · Tarantula Nebula (30 Doradus) zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_westerlund · Flight through star cluster Westerlund 2 (ESA/Hubble)"
+            - option "cosmos_southernring · Southern Ring Nebula zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_carina_eso · Carina Nebula zoom (ESO)"
+          - button "🎲 Re-roll random" [ref=e79] [cursor=pointer]
+        - group "Active clip" [ref=e80]:
+          - generic [ref=e81]: Active clip
+          - generic [ref=e82]:
+            - term [ref=e83]: id
+            - definition [ref=e84]: cosmos
+            - term [ref=e85]: title
+            - definition [ref=e86]: Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+            - term [ref=e87]: source
+            - definition [ref=e88]: NASA SVS 31348 Clifs-3d-STScI (Exploring the Cosmic Cliffs in 3D, Webb NIRCam); 4K source, trim 10–34s, crossfade-loop. Text-free — replaces the Orion SVS 30957 flythrough.
+            - term [ref=e89]: license
+            - definition [ref=e90]: CC-BY-class — credit NASA, ESA, CSA, STScI
+            - term [ref=e91]: base_file
+            - definition [ref=e92]: cosmos/base.mp4
+        - group "Annotations & affect" [ref=e93]:
+          - generic [ref=e94]: Annotations & affect
+          - generic [ref=e95]:
+            - generic [ref=e96]: detected.nebula · sal 4 · 4 tiers
+            - generic [ref=e97]: detected.star · sal 2 · 4 tiers
+            - generic [ref=e98]: measure.distance · min L3 · 1 tier
+            - generic [ref=e99]: feel.wonder · min L1 · 4 tiers
+            - generic [ref=e100]: feel.sublime · min L2 · 4 tiers
+            - generic [ref=e101]: feel.vastness · min L3 · 4 tiers
+            - generic [ref=e102]: feel.insignificance · min L4 · 4 tiers
+        - group "RenderPlan" [ref=e103]:
+          - generic [ref=e104]: RenderPlan
+          - generic [ref=e105]: "{ \"plan\": { \"grade\": { \"tone\": 0 }, \"overlay\": { \"level\": 0, \"intensity\": 0 }, \"affect\": { \"strength\": 0, \"intensity\": 0 }, \"dream\": { \"strength\": 0, \"intensity\": 0 }, \"is_identity\": true }, \"render\": { \"video\": { \"shown\": false }, \"audio\": { \"source\": \"off\", \"url\": null, \"altitude_coupled\": false } } }"
+        - group "Cache & playback" [ref=e106]:
+          - generic [ref=e107]: Cache & playback
+          - generic [ref=e108]:
+            - term [ref=e109]: cache
+            - definition [ref=e110]: 496/41 cached
+            - term [ref=e111]: active source
+            - definition [ref=e112]: memory (blob)
+            - term [ref=e113]: resolution
+            - definition [ref=e114]: —
+            - term [ref=e115]: duration
+            - definition [ref=e116]: —
+            - term [ref=e117]: loop pos
+            - definition [ref=e118]: —
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // These assert the two behaviors the operator asked for:
+  4   | //   1. zooming plays the morph matching the clip we land on, and
+  5   | //   2. after landing the clip is LOCKED — it does not change while parked.
+  6   | //
+  7   | // The played morph paths are read from window.__hefMorphs (a diagnostic seam in
+  8   | // advance()), which is reliable even when the morph is served from an in-memory
+  9   | // blob cache. The locked clip is read from the Dev-Mode "#scale-name" readout
+  10  | // ("<scale> · <clip>  (i/n)").
+  11  | 
+  12  | async function boot(page: Page) {
+  13  |   await page.addInitScript(() => {
+  14  |     localStorage.setItem("hef.devMode", "1");
+  15  |   });
+  16  |   await page.goto("/");
+  17  |   // Wait for phase-1 preload, then enter via the welcome screen's Launch button
+  18  |   // (Video defaults on, Audio 2 → the experience is running once we're in).
+> 19  |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  20  |   await page.locator("#welcome-launch").click();
+  21  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  22  |   await expect(page.locator("#scale-name")).toContainText("cosmos");
+  23  | }
+  24  | 
+  25  | async function morphs(page: Page): Promise<string[]> {
+  26  |   return await page.evaluate(() => (window as any).__hefMorphs || []);
+  27  | }
+  28  | 
+  29  | async function wheelOnStage(page: Page, deltaY: number) {
+  30  |   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
+  31  | }
+  32  | 
+  33  | // The Audio control is a 0–10 level slider; set it to full + fire `input` directly
+  34  | // (headless Chromium relaxes the autoplay gesture requirement).
+  35  | async function enableAudio(page: Page) {
+  36  |   await page.evaluate(() => {
+  37  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  38  |     c.value = "10";
+  39  |     c.dispatchEvent(new Event("input", { bubbles: true }));
+  40  |   });
+  41  | }
+  42  | 
+  43  | // The Video toggle gates the base-clip loop (update() only loads media when video is
+  44  | // shown). Same hidden-checkbox pattern.
+  45  | async function enableVideo(page: Page) {
+  46  |   await page.evaluate(() => {
+  47  |     const c = document.querySelector("#visual") as HTMLInputElement;
+  48  |     c.checked = true;
+  49  |     c.dispatchEvent(new Event("change", { bubbles: true }));
+  50  |   });
+  51  | }
+  52  | 
+  53  | test("two audio elements exist for crossfade", async ({ page }) => {
+  54  |   await boot(page);
+  55  |   const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  56  |   expect(n).toBe(2);
+  57  | });
+  58  | 
+  59  | test("a new volume fade supersedes a stale one (audio not silenced after landing)", async ({ page }) => {
+  60  |   await boot(page);
+  61  |   // Reproduce the race: a fade-to-0 in flight, then the same element is brought back
+  62  |   // up (as happens when a faded idle element becomes the newly-landed active scale).
+  63  |   // The stale fade must NOT drag it back to 0.
+  64  |   const vol = await page.evaluate(async () => {
+  65  |     const a = document.querySelector("#aud") as HTMLAudioElement;
+  66  |     a.volume = 1;
+  67  |     (window as any).__hefFade(a, 0, 600);              // start a slow fade to 0
+  68  |     await new Promise((r) => setTimeout(r, 120));      // let it ramp partway down
+  69  |     (window as any).__hefFade(a, 0.8, 90);             // new fade up — must cancel the old one
+  70  |     await new Promise((r) => setTimeout(r, 350));      // well past both fades
+  71  |     return a.volume;
+  72  |   });
+  73  |   expect(vol).toBeGreaterThan(0.7);                    // ended near 0.8, not dragged to 0
+  74  | });
+  75  | 
+  76  | test("audio is a 0-10 level dial", async ({ page }) => {
+  77  |   await boot(page);
+  78  |   const ctl = await page.evaluate(() => {
+  79  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  80  |     return { type: c.type, min: c.min, max: c.max };
+  81  |   });
+  82  |   expect(ctl.type).toBe("range");
+  83  |   expect(ctl.min).toBe("0");
+  84  |   expect(ctl.max).toBe("10");
+  85  | });
+  86  | 
+  87  | // (Entry via the welcome screen — defaults, Launch, control carry-over, State B —
+  88  | // is covered in welcome.spec.ts.)
+  89  | 
+  90  | test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  91  |   await boot(page);
+  92  |   await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  93  |   const box = (await page.locator("#dial").boundingBox())!;
+  94  |   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  95  |   await page.mouse.move(cx, cy - 30);
+  96  |   await page.mouse.down();
+  97  |   await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  98  |   // The currentTime seek is throttled to one rAF; wait for it to land.
+  99  |   await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  100 |   const state = await page.evaluate(() => ({
+  101 |     t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+  102 |     ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+  103 |     gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  104 |   }));
+  105 |   expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  106 |   expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  107 |   expect(state.ga).toBeLessThan(1);            // current scale fading out
+  108 |   await page.mouse.up();
+  109 | });
+  110 | 
+  111 | test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  112 |   await boot(page);
+  113 |   const start = (await page.locator("#scale-name").textContent())!;
+  114 |   await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  115 |   await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  116 |   const landed = (await page.locator("#scale-name").textContent())!;
+  117 |   expect(landed).toContain("orbit");
+  118 |   await page.waitForTimeout(1500);
+  119 |   expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/altitude-lock-auto-scrub-s-cb764-tep-jump-takes-2x-a-1-step-/error-context.md b/simulator/e2e/test-results/altitude-lock-auto-scrub-s-cb764-tep-jump-takes-2x-a-1-step-/error-context.md
new file mode 100644
index 0000000..8b18286
--- /dev/null
+++ b/simulator/e2e/test-results/altitude-lock-auto-scrub-s-cb764-tep-jump-takes-2x-a-1-step-/error-context.md
@@ -0,0 +1,267 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: altitude-lock.spec.ts >> auto-scrub speed is constant per altitude (a 2-step jump takes ~2x a 1-step)
+- Location: tests/altitude-lock.spec.ts:122:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode" [checked]
+        - generic [ref=e69]: Dev Mode
+      - generic [ref=e70]:
+        - group "Audio diagnostics" [ref=e71]:
+          - generic [ref=e72]: Audio diagnostics
+          - generic [ref=e73]: "audio: off (level 0)"
+          - paragraph [ref=e74]: Native player — tests the soundtrack file directly (bypasses all app code). If it plays here but the Audio toggle is silent, it's a code/autoplay issue, not the file.
+        - group "Pool — pick a clip" [ref=e76]:
+          - generic [ref=e77]: Pool — pick a clip
+          - combobox "Choose a clip from this altitude's pool" [ref=e78]:
+            - option "cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)" [selected]
+            - option "cosmos_galaxies · Flying Through Galaxies (NASA SVS)"
+            - option "cosmos_orion · Orion Nebula — visible/IR flythrough (NASA SVS)"
+            - option "cosmos_tarantula · Tarantula Nebula (30 Doradus) zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_westerlund · Flight through star cluster Westerlund 2 (ESA/Hubble)"
+            - option "cosmos_southernring · Southern Ring Nebula zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_carina_eso · Carina Nebula zoom (ESO)"
+          - button "🎲 Re-roll random" [ref=e79] [cursor=pointer]
+        - group "Active clip" [ref=e80]:
+          - generic [ref=e81]: Active clip
+          - generic [ref=e82]:
+            - term [ref=e83]: id
+            - definition [ref=e84]: cosmos
+            - term [ref=e85]: title
+            - definition [ref=e86]: Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+            - term [ref=e87]: source
+            - definition [ref=e88]: NASA SVS 31348 Clifs-3d-STScI (Exploring the Cosmic Cliffs in 3D, Webb NIRCam); 4K source, trim 10–34s, crossfade-loop. Text-free — replaces the Orion SVS 30957 flythrough.
+            - term [ref=e89]: license
+            - definition [ref=e90]: CC-BY-class — credit NASA, ESA, CSA, STScI
+            - term [ref=e91]: base_file
+            - definition [ref=e92]: cosmos/base.mp4
+        - group "Annotations & affect" [ref=e93]:
+          - generic [ref=e94]: Annotations & affect
+          - generic [ref=e95]:
+            - generic [ref=e96]: detected.nebula · sal 4 · 4 tiers
+            - generic [ref=e97]: detected.star · sal 2 · 4 tiers
+            - generic [ref=e98]: measure.distance · min L3 · 1 tier
+            - generic [ref=e99]: feel.wonder · min L1 · 4 tiers
+            - generic [ref=e100]: feel.sublime · min L2 · 4 tiers
+            - generic [ref=e101]: feel.vastness · min L3 · 4 tiers
+            - generic [ref=e102]: feel.insignificance · min L4 · 4 tiers
+        - group "RenderPlan" [ref=e103]:
+          - generic [ref=e104]: RenderPlan
+          - generic [ref=e105]: "{ \"plan\": { \"grade\": { \"tone\": 0 }, \"overlay\": { \"level\": 0, \"intensity\": 0 }, \"affect\": { \"strength\": 0, \"intensity\": 0 }, \"dream\": { \"strength\": 0, \"intensity\": 0 }, \"is_identity\": true }, \"render\": { \"video\": { \"shown\": false }, \"audio\": { \"source\": \"off\", \"url\": null, \"altitude_coupled\": false } } }"
+        - group "Cache & playback" [ref=e106]:
+          - generic [ref=e107]: Cache & playback
+          - generic [ref=e108]:
+            - term [ref=e109]: cache
+            - definition [ref=e110]: 496/41 cached
+            - term [ref=e111]: active source
+            - definition [ref=e112]: memory (blob)
+            - term [ref=e113]: resolution
+            - definition [ref=e114]: —
+            - term [ref=e115]: duration
+            - definition [ref=e116]: —
+            - term [ref=e117]: loop pos
+            - definition [ref=e118]: —
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // These assert the two behaviors the operator asked for:
+  4   | //   1. zooming plays the morph matching the clip we land on, and
+  5   | //   2. after landing the clip is LOCKED — it does not change while parked.
+  6   | //
+  7   | // The played morph paths are read from window.__hefMorphs (a diagnostic seam in
+  8   | // advance()), which is reliable even when the morph is served from an in-memory
+  9   | // blob cache. The locked clip is read from the Dev-Mode "#scale-name" readout
+  10  | // ("<scale> · <clip>  (i/n)").
+  11  | 
+  12  | async function boot(page: Page) {
+  13  |   await page.addInitScript(() => {
+  14  |     localStorage.setItem("hef.devMode", "1");
+  15  |   });
+  16  |   await page.goto("/");
+  17  |   // Wait for phase-1 preload, then enter via the welcome screen's Launch button
+  18  |   // (Video defaults on, Audio 2 → the experience is running once we're in).
+> 19  |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  20  |   await page.locator("#welcome-launch").click();
+  21  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  22  |   await expect(page.locator("#scale-name")).toContainText("cosmos");
+  23  | }
+  24  | 
+  25  | async function morphs(page: Page): Promise<string[]> {
+  26  |   return await page.evaluate(() => (window as any).__hefMorphs || []);
+  27  | }
+  28  | 
+  29  | async function wheelOnStage(page: Page, deltaY: number) {
+  30  |   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
+  31  | }
+  32  | 
+  33  | // The Audio control is a 0–10 level slider; set it to full + fire `input` directly
+  34  | // (headless Chromium relaxes the autoplay gesture requirement).
+  35  | async function enableAudio(page: Page) {
+  36  |   await page.evaluate(() => {
+  37  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  38  |     c.value = "10";
+  39  |     c.dispatchEvent(new Event("input", { bubbles: true }));
+  40  |   });
+  41  | }
+  42  | 
+  43  | // The Video toggle gates the base-clip loop (update() only loads media when video is
+  44  | // shown). Same hidden-checkbox pattern.
+  45  | async function enableVideo(page: Page) {
+  46  |   await page.evaluate(() => {
+  47  |     const c = document.querySelector("#visual") as HTMLInputElement;
+  48  |     c.checked = true;
+  49  |     c.dispatchEvent(new Event("change", { bubbles: true }));
+  50  |   });
+  51  | }
+  52  | 
+  53  | test("two audio elements exist for crossfade", async ({ page }) => {
+  54  |   await boot(page);
+  55  |   const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  56  |   expect(n).toBe(2);
+  57  | });
+  58  | 
+  59  | test("a new volume fade supersedes a stale one (audio not silenced after landing)", async ({ page }) => {
+  60  |   await boot(page);
+  61  |   // Reproduce the race: a fade-to-0 in flight, then the same element is brought back
+  62  |   // up (as happens when a faded idle element becomes the newly-landed active scale).
+  63  |   // The stale fade must NOT drag it back to 0.
+  64  |   const vol = await page.evaluate(async () => {
+  65  |     const a = document.querySelector("#aud") as HTMLAudioElement;
+  66  |     a.volume = 1;
+  67  |     (window as any).__hefFade(a, 0, 600);              // start a slow fade to 0
+  68  |     await new Promise((r) => setTimeout(r, 120));      // let it ramp partway down
+  69  |     (window as any).__hefFade(a, 0.8, 90);             // new fade up — must cancel the old one
+  70  |     await new Promise((r) => setTimeout(r, 350));      // well past both fades
+  71  |     return a.volume;
+  72  |   });
+  73  |   expect(vol).toBeGreaterThan(0.7);                    // ended near 0.8, not dragged to 0
+  74  | });
+  75  | 
+  76  | test("audio is a 0-10 level dial", async ({ page }) => {
+  77  |   await boot(page);
+  78  |   const ctl = await page.evaluate(() => {
+  79  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  80  |     return { type: c.type, min: c.min, max: c.max };
+  81  |   });
+  82  |   expect(ctl.type).toBe("range");
+  83  |   expect(ctl.min).toBe("0");
+  84  |   expect(ctl.max).toBe("10");
+  85  | });
+  86  | 
+  87  | // (Entry via the welcome screen — defaults, Launch, control carry-over, State B —
+  88  | // is covered in welcome.spec.ts.)
+  89  | 
+  90  | test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  91  |   await boot(page);
+  92  |   await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  93  |   const box = (await page.locator("#dial").boundingBox())!;
+  94  |   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  95  |   await page.mouse.move(cx, cy - 30);
+  96  |   await page.mouse.down();
+  97  |   await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  98  |   // The currentTime seek is throttled to one rAF; wait for it to land.
+  99  |   await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  100 |   const state = await page.evaluate(() => ({
+  101 |     t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+  102 |     ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+  103 |     gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  104 |   }));
+  105 |   expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  106 |   expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  107 |   expect(state.ga).toBeLessThan(1);            // current scale fading out
+  108 |   await page.mouse.up();
+  109 | });
+  110 | 
+  111 | test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  112 |   await boot(page);
+  113 |   const start = (await page.locator("#scale-name").textContent())!;
+  114 |   await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  115 |   await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  116 |   const landed = (await page.locator("#scale-name").textContent())!;
+  117 |   expect(landed).toContain("orbit");
+  118 |   await page.waitForTimeout(1500);
+  119 |   expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/altitude-lock-dragging-the-07d2b-currentTime-and-audio-gains/error-context.md b/simulator/e2e/test-results/altitude-lock-dragging-the-07d2b-currentTime-and-audio-gains/error-context.md
new file mode 100644
index 0000000..d7db140
--- /dev/null
+++ b/simulator/e2e/test-results/altitude-lock-dragging-the-07d2b-currentTime-and-audio-gains/error-context.md
@@ -0,0 +1,267 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: altitude-lock.spec.ts >> dragging the dial scrubs morph currentTime and audio gains
+- Location: tests/altitude-lock.spec.ts:90:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode" [checked]
+        - generic [ref=e69]: Dev Mode
+      - generic [ref=e70]:
+        - group "Audio diagnostics" [ref=e71]:
+          - generic [ref=e72]: Audio diagnostics
+          - generic [ref=e73]: "audio: off (level 0)"
+          - paragraph [ref=e74]: Native player — tests the soundtrack file directly (bypasses all app code). If it plays here but the Audio toggle is silent, it's a code/autoplay issue, not the file.
+        - group "Pool — pick a clip" [ref=e76]:
+          - generic [ref=e77]: Pool — pick a clip
+          - combobox "Choose a clip from this altitude's pool" [ref=e78]:
+            - option "cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)" [selected]
+            - option "cosmos_galaxies · Flying Through Galaxies (NASA SVS)"
+            - option "cosmos_orion · Orion Nebula — visible/IR flythrough (NASA SVS)"
+            - option "cosmos_tarantula · Tarantula Nebula (30 Doradus) zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_westerlund · Flight through star cluster Westerlund 2 (ESA/Hubble)"
+            - option "cosmos_southernring · Southern Ring Nebula zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_carina_eso · Carina Nebula zoom (ESO)"
+          - button "🎲 Re-roll random" [ref=e79] [cursor=pointer]
+        - group "Active clip" [ref=e80]:
+          - generic [ref=e81]: Active clip
+          - generic [ref=e82]:
+            - term [ref=e83]: id
+            - definition [ref=e84]: cosmos
+            - term [ref=e85]: title
+            - definition [ref=e86]: Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+            - term [ref=e87]: source
+            - definition [ref=e88]: NASA SVS 31348 Clifs-3d-STScI (Exploring the Cosmic Cliffs in 3D, Webb NIRCam); 4K source, trim 10–34s, crossfade-loop. Text-free — replaces the Orion SVS 30957 flythrough.
+            - term [ref=e89]: license
+            - definition [ref=e90]: CC-BY-class — credit NASA, ESA, CSA, STScI
+            - term [ref=e91]: base_file
+            - definition [ref=e92]: cosmos/base.mp4
+        - group "Annotations & affect" [ref=e93]:
+          - generic [ref=e94]: Annotations & affect
+          - generic [ref=e95]:
+            - generic [ref=e96]: detected.nebula · sal 4 · 4 tiers
+            - generic [ref=e97]: detected.star · sal 2 · 4 tiers
+            - generic [ref=e98]: measure.distance · min L3 · 1 tier
+            - generic [ref=e99]: feel.wonder · min L1 · 4 tiers
+            - generic [ref=e100]: feel.sublime · min L2 · 4 tiers
+            - generic [ref=e101]: feel.vastness · min L3 · 4 tiers
+            - generic [ref=e102]: feel.insignificance · min L4 · 4 tiers
+        - group "RenderPlan" [ref=e103]:
+          - generic [ref=e104]: RenderPlan
+          - generic [ref=e105]: "{ \"plan\": { \"grade\": { \"tone\": 0 }, \"overlay\": { \"level\": 0, \"intensity\": 0 }, \"affect\": { \"strength\": 0, \"intensity\": 0 }, \"dream\": { \"strength\": 0, \"intensity\": 0 }, \"is_identity\": true }, \"render\": { \"video\": { \"shown\": false }, \"audio\": { \"source\": \"off\", \"url\": null, \"altitude_coupled\": false } } }"
+        - group "Cache & playback" [ref=e106]:
+          - generic [ref=e107]: Cache & playback
+          - generic [ref=e108]:
+            - term [ref=e109]: cache
+            - definition [ref=e110]: 497/41 cached
+            - term [ref=e111]: active source
+            - definition [ref=e112]: memory (blob)
+            - term [ref=e113]: resolution
+            - definition [ref=e114]: —
+            - term [ref=e115]: duration
+            - definition [ref=e116]: —
+            - term [ref=e117]: loop pos
+            - definition [ref=e118]: —
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // These assert the two behaviors the operator asked for:
+  4   | //   1. zooming plays the morph matching the clip we land on, and
+  5   | //   2. after landing the clip is LOCKED — it does not change while parked.
+  6   | //
+  7   | // The played morph paths are read from window.__hefMorphs (a diagnostic seam in
+  8   | // advance()), which is reliable even when the morph is served from an in-memory
+  9   | // blob cache. The locked clip is read from the Dev-Mode "#scale-name" readout
+  10  | // ("<scale> · <clip>  (i/n)").
+  11  | 
+  12  | async function boot(page: Page) {
+  13  |   await page.addInitScript(() => {
+  14  |     localStorage.setItem("hef.devMode", "1");
+  15  |   });
+  16  |   await page.goto("/");
+  17  |   // Wait for phase-1 preload, then enter via the welcome screen's Launch button
+  18  |   // (Video defaults on, Audio 2 → the experience is running once we're in).
+> 19  |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  20  |   await page.locator("#welcome-launch").click();
+  21  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  22  |   await expect(page.locator("#scale-name")).toContainText("cosmos");
+  23  | }
+  24  | 
+  25  | async function morphs(page: Page): Promise<string[]> {
+  26  |   return await page.evaluate(() => (window as any).__hefMorphs || []);
+  27  | }
+  28  | 
+  29  | async function wheelOnStage(page: Page, deltaY: number) {
+  30  |   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
+  31  | }
+  32  | 
+  33  | // The Audio control is a 0–10 level slider; set it to full + fire `input` directly
+  34  | // (headless Chromium relaxes the autoplay gesture requirement).
+  35  | async function enableAudio(page: Page) {
+  36  |   await page.evaluate(() => {
+  37  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  38  |     c.value = "10";
+  39  |     c.dispatchEvent(new Event("input", { bubbles: true }));
+  40  |   });
+  41  | }
+  42  | 
+  43  | // The Video toggle gates the base-clip loop (update() only loads media when video is
+  44  | // shown). Same hidden-checkbox pattern.
+  45  | async function enableVideo(page: Page) {
+  46  |   await page.evaluate(() => {
+  47  |     const c = document.querySelector("#visual") as HTMLInputElement;
+  48  |     c.checked = true;
+  49  |     c.dispatchEvent(new Event("change", { bubbles: true }));
+  50  |   });
+  51  | }
+  52  | 
+  53  | test("two audio elements exist for crossfade", async ({ page }) => {
+  54  |   await boot(page);
+  55  |   const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  56  |   expect(n).toBe(2);
+  57  | });
+  58  | 
+  59  | test("a new volume fade supersedes a stale one (audio not silenced after landing)", async ({ page }) => {
+  60  |   await boot(page);
+  61  |   // Reproduce the race: a fade-to-0 in flight, then the same element is brought back
+  62  |   // up (as happens when a faded idle element becomes the newly-landed active scale).
+  63  |   // The stale fade must NOT drag it back to 0.
+  64  |   const vol = await page.evaluate(async () => {
+  65  |     const a = document.querySelector("#aud") as HTMLAudioElement;
+  66  |     a.volume = 1;
+  67  |     (window as any).__hefFade(a, 0, 600);              // start a slow fade to 0
+  68  |     await new Promise((r) => setTimeout(r, 120));      // let it ramp partway down
+  69  |     (window as any).__hefFade(a, 0.8, 90);             // new fade up — must cancel the old one
+  70  |     await new Promise((r) => setTimeout(r, 350));      // well past both fades
+  71  |     return a.volume;
+  72  |   });
+  73  |   expect(vol).toBeGreaterThan(0.7);                    // ended near 0.8, not dragged to 0
+  74  | });
+  75  | 
+  76  | test("audio is a 0-10 level dial", async ({ page }) => {
+  77  |   await boot(page);
+  78  |   const ctl = await page.evaluate(() => {
+  79  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  80  |     return { type: c.type, min: c.min, max: c.max };
+  81  |   });
+  82  |   expect(ctl.type).toBe("range");
+  83  |   expect(ctl.min).toBe("0");
+  84  |   expect(ctl.max).toBe("10");
+  85  | });
+  86  | 
+  87  | // (Entry via the welcome screen — defaults, Launch, control carry-over, State B —
+  88  | // is covered in welcome.spec.ts.)
+  89  | 
+  90  | test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  91  |   await boot(page);
+  92  |   await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  93  |   const box = (await page.locator("#dial").boundingBox())!;
+  94  |   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  95  |   await page.mouse.move(cx, cy - 30);
+  96  |   await page.mouse.down();
+  97  |   await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  98  |   // The currentTime seek is throttled to one rAF; wait for it to land.
+  99  |   await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  100 |   const state = await page.evaluate(() => ({
+  101 |     t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+  102 |     ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+  103 |     gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  104 |   }));
+  105 |   expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  106 |   expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  107 |   expect(state.ga).toBeLessThan(1);            // current scale fading out
+  108 |   await page.mouse.up();
+  109 | });
+  110 | 
+  111 | test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  112 |   await boot(page);
+  113 |   const start = (await page.locator("#scale-name").textContent())!;
+  114 |   await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  115 |   await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  116 |   const landed = (await page.locator("#scale-name").textContent())!;
+  117 |   expect(landed).toContain("orbit");
+  118 |   await page.waitForTimeout(1500);
+  119 |   expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/altitude-lock-two-audio-elements-exist-for-crossfade/error-context.md b/simulator/e2e/test-results/altitude-lock-two-audio-elements-exist-for-crossfade/error-context.md
new file mode 100644
index 0000000..3e76f39
--- /dev/null
+++ b/simulator/e2e/test-results/altitude-lock-two-audio-elements-exist-for-crossfade/error-context.md
@@ -0,0 +1,147 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: altitude-lock.spec.ts >> two audio elements exist for crossfade
+- Location: tests/altitude-lock.spec.ts:53:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [ref=e2]: "{\"detail\":\"Not Found\"}"
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // These assert the two behaviors the operator asked for:
+  4   | //   1. zooming plays the morph matching the clip we land on, and
+  5   | //   2. after landing the clip is LOCKED — it does not change while parked.
+  6   | //
+  7   | // The played morph paths are read from window.__hefMorphs (a diagnostic seam in
+  8   | // advance()), which is reliable even when the morph is served from an in-memory
+  9   | // blob cache. The locked clip is read from the Dev-Mode "#scale-name" readout
+  10  | // ("<scale> · <clip>  (i/n)").
+  11  | 
+  12  | async function boot(page: Page) {
+  13  |   await page.addInitScript(() => {
+  14  |     localStorage.setItem("hef.devMode", "1");
+  15  |   });
+  16  |   await page.goto("/");
+  17  |   // Wait for phase-1 preload, then enter via the welcome screen's Launch button
+  18  |   // (Video defaults on, Audio 2 → the experience is running once we're in).
+> 19  |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  20  |   await page.locator("#welcome-launch").click();
+  21  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  22  |   await expect(page.locator("#scale-name")).toContainText("cosmos");
+  23  | }
+  24  | 
+  25  | async function morphs(page: Page): Promise<string[]> {
+  26  |   return await page.evaluate(() => (window as any).__hefMorphs || []);
+  27  | }
+  28  | 
+  29  | async function wheelOnStage(page: Page, deltaY: number) {
+  30  |   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
+  31  | }
+  32  | 
+  33  | // The Audio control is a 0–10 level slider; set it to full + fire `input` directly
+  34  | // (headless Chromium relaxes the autoplay gesture requirement).
+  35  | async function enableAudio(page: Page) {
+  36  |   await page.evaluate(() => {
+  37  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  38  |     c.value = "10";
+  39  |     c.dispatchEvent(new Event("input", { bubbles: true }));
+  40  |   });
+  41  | }
+  42  | 
+  43  | // The Video toggle gates the base-clip loop (update() only loads media when video is
+  44  | // shown). Same hidden-checkbox pattern.
+  45  | async function enableVideo(page: Page) {
+  46  |   await page.evaluate(() => {
+  47  |     const c = document.querySelector("#visual") as HTMLInputElement;
+  48  |     c.checked = true;
+  49  |     c.dispatchEvent(new Event("change", { bubbles: true }));
+  50  |   });
+  51  | }
+  52  | 
+  53  | test("two audio elements exist for crossfade", async ({ page }) => {
+  54  |   await boot(page);
+  55  |   const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  56  |   expect(n).toBe(2);
+  57  | });
+  58  | 
+  59  | test("a new volume fade supersedes a stale one (audio not silenced after landing)", async ({ page }) => {
+  60  |   await boot(page);
+  61  |   // Reproduce the race: a fade-to-0 in flight, then the same element is brought back
+  62  |   // up (as happens when a faded idle element becomes the newly-landed active scale).
+  63  |   // The stale fade must NOT drag it back to 0.
+  64  |   const vol = await page.evaluate(async () => {
+  65  |     const a = document.querySelector("#aud") as HTMLAudioElement;
+  66  |     a.volume = 1;
+  67  |     (window as any).__hefFade(a, 0, 600);              // start a slow fade to 0
+  68  |     await new Promise((r) => setTimeout(r, 120));      // let it ramp partway down
+  69  |     (window as any).__hefFade(a, 0.8, 90);             // new fade up — must cancel the old one
+  70  |     await new Promise((r) => setTimeout(r, 350));      // well past both fades
+  71  |     return a.volume;
+  72  |   });
+  73  |   expect(vol).toBeGreaterThan(0.7);                    // ended near 0.8, not dragged to 0
+  74  | });
+  75  | 
+  76  | test("audio is a 0-10 level dial", async ({ page }) => {
+  77  |   await boot(page);
+  78  |   const ctl = await page.evaluate(() => {
+  79  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  80  |     return { type: c.type, min: c.min, max: c.max };
+  81  |   });
+  82  |   expect(ctl.type).toBe("range");
+  83  |   expect(ctl.min).toBe("0");
+  84  |   expect(ctl.max).toBe("10");
+  85  | });
+  86  | 
+  87  | // (Entry via the welcome screen — defaults, Launch, control carry-over, State B —
+  88  | // is covered in welcome.spec.ts.)
+  89  | 
+  90  | test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  91  |   await boot(page);
+  92  |   await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  93  |   const box = (await page.locator("#dial").boundingBox())!;
+  94  |   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  95  |   await page.mouse.move(cx, cy - 30);
+  96  |   await page.mouse.down();
+  97  |   await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  98  |   // The currentTime seek is throttled to one rAF; wait for it to land.
+  99  |   await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  100 |   const state = await page.evaluate(() => ({
+  101 |     t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+  102 |     ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+  103 |     gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  104 |   }));
+  105 |   expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  106 |   expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  107 |   expect(state.ga).toBeLessThan(1);            // current scale fading out
+  108 |   await page.mouse.up();
+  109 | });
+  110 | 
+  111 | test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  112 |   await boot(page);
+  113 |   const start = (await page.locator("#scale-name").textContent())!;
+  114 |   await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  115 |   await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  116 |   const landed = (await page.locator("#scale-name").textContent())!;
+  117 |   expect(landed).toContain("orbit");
+  118 |   await page.waitForTimeout(1500);
+  119 |   expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/altitude-lock-wheel-auto-scrubs-one-altitude-and-locks/error-context.md b/simulator/e2e/test-results/altitude-lock-wheel-auto-scrubs-one-altitude-and-locks/error-context.md
new file mode 100644
index 0000000..a7d8769
--- /dev/null
+++ b/simulator/e2e/test-results/altitude-lock-wheel-auto-scrubs-one-altitude-and-locks/error-context.md
@@ -0,0 +1,267 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: altitude-lock.spec.ts >> wheel auto-scrubs one altitude and locks
+- Location: tests/altitude-lock.spec.ts:111:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode" [checked]
+        - generic [ref=e69]: Dev Mode
+      - generic [ref=e70]:
+        - group "Audio diagnostics" [ref=e71]:
+          - generic [ref=e72]: Audio diagnostics
+          - generic [ref=e73]: "audio: off (level 0)"
+          - paragraph [ref=e74]: Native player — tests the soundtrack file directly (bypasses all app code). If it plays here but the Audio toggle is silent, it's a code/autoplay issue, not the file.
+        - group "Pool — pick a clip" [ref=e76]:
+          - generic [ref=e77]: Pool — pick a clip
+          - combobox "Choose a clip from this altitude's pool" [ref=e78]:
+            - option "cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)" [selected]
+            - option "cosmos_galaxies · Flying Through Galaxies (NASA SVS)"
+            - option "cosmos_orion · Orion Nebula — visible/IR flythrough (NASA SVS)"
+            - option "cosmos_tarantula · Tarantula Nebula (30 Doradus) zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_westerlund · Flight through star cluster Westerlund 2 (ESA/Hubble)"
+            - option "cosmos_southernring · Southern Ring Nebula zoom (NASA/ESA/CSA/STScI)"
+            - option "cosmos_carina_eso · Carina Nebula zoom (ESO)"
+          - button "🎲 Re-roll random" [ref=e79] [cursor=pointer]
+        - group "Active clip" [ref=e80]:
+          - generic [ref=e81]: Active clip
+          - generic [ref=e82]:
+            - term [ref=e83]: id
+            - definition [ref=e84]: cosmos
+            - term [ref=e85]: title
+            - definition [ref=e86]: Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+            - term [ref=e87]: source
+            - definition [ref=e88]: NASA SVS 31348 Clifs-3d-STScI (Exploring the Cosmic Cliffs in 3D, Webb NIRCam); 4K source, trim 10–34s, crossfade-loop. Text-free — replaces the Orion SVS 30957 flythrough.
+            - term [ref=e89]: license
+            - definition [ref=e90]: CC-BY-class — credit NASA, ESA, CSA, STScI
+            - term [ref=e91]: base_file
+            - definition [ref=e92]: cosmos/base.mp4
+        - group "Annotations & affect" [ref=e93]:
+          - generic [ref=e94]: Annotations & affect
+          - generic [ref=e95]:
+            - generic [ref=e96]: detected.nebula · sal 4 · 4 tiers
+            - generic [ref=e97]: detected.star · sal 2 · 4 tiers
+            - generic [ref=e98]: measure.distance · min L3 · 1 tier
+            - generic [ref=e99]: feel.wonder · min L1 · 4 tiers
+            - generic [ref=e100]: feel.sublime · min L2 · 4 tiers
+            - generic [ref=e101]: feel.vastness · min L3 · 4 tiers
+            - generic [ref=e102]: feel.insignificance · min L4 · 4 tiers
+        - group "RenderPlan" [ref=e103]:
+          - generic [ref=e104]: RenderPlan
+          - generic [ref=e105]: "{ \"plan\": { \"grade\": { \"tone\": 0 }, \"overlay\": { \"level\": 0, \"intensity\": 0 }, \"affect\": { \"strength\": 0, \"intensity\": 0 }, \"dream\": { \"strength\": 0, \"intensity\": 0 }, \"is_identity\": true }, \"render\": { \"video\": { \"shown\": false }, \"audio\": { \"source\": \"off\", \"url\": null, \"altitude_coupled\": false } } }"
+        - group "Cache & playback" [ref=e106]:
+          - generic [ref=e107]: Cache & playback
+          - generic [ref=e108]:
+            - term [ref=e109]: cache
+            - definition [ref=e110]: 497/41 cached
+            - term [ref=e111]: active source
+            - definition [ref=e112]: memory (blob)
+            - term [ref=e113]: resolution
+            - definition [ref=e114]: —
+            - term [ref=e115]: duration
+            - definition [ref=e116]: —
+            - term [ref=e117]: loop pos
+            - definition [ref=e118]: —
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // These assert the two behaviors the operator asked for:
+  4   | //   1. zooming plays the morph matching the clip we land on, and
+  5   | //   2. after landing the clip is LOCKED — it does not change while parked.
+  6   | //
+  7   | // The played morph paths are read from window.__hefMorphs (a diagnostic seam in
+  8   | // advance()), which is reliable even when the morph is served from an in-memory
+  9   | // blob cache. The locked clip is read from the Dev-Mode "#scale-name" readout
+  10  | // ("<scale> · <clip>  (i/n)").
+  11  | 
+  12  | async function boot(page: Page) {
+  13  |   await page.addInitScript(() => {
+  14  |     localStorage.setItem("hef.devMode", "1");
+  15  |   });
+  16  |   await page.goto("/");
+  17  |   // Wait for phase-1 preload, then enter via the welcome screen's Launch button
+  18  |   // (Video defaults on, Audio 2 → the experience is running once we're in).
+> 19  |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  20  |   await page.locator("#welcome-launch").click();
+  21  |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  22  |   await expect(page.locator("#scale-name")).toContainText("cosmos");
+  23  | }
+  24  | 
+  25  | async function morphs(page: Page): Promise<string[]> {
+  26  |   return await page.evaluate(() => (window as any).__hefMorphs || []);
+  27  | }
+  28  | 
+  29  | async function wheelOnStage(page: Page, deltaY: number) {
+  30  |   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
+  31  | }
+  32  | 
+  33  | // The Audio control is a 0–10 level slider; set it to full + fire `input` directly
+  34  | // (headless Chromium relaxes the autoplay gesture requirement).
+  35  | async function enableAudio(page: Page) {
+  36  |   await page.evaluate(() => {
+  37  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  38  |     c.value = "10";
+  39  |     c.dispatchEvent(new Event("input", { bubbles: true }));
+  40  |   });
+  41  | }
+  42  | 
+  43  | // The Video toggle gates the base-clip loop (update() only loads media when video is
+  44  | // shown). Same hidden-checkbox pattern.
+  45  | async function enableVideo(page: Page) {
+  46  |   await page.evaluate(() => {
+  47  |     const c = document.querySelector("#visual") as HTMLInputElement;
+  48  |     c.checked = true;
+  49  |     c.dispatchEvent(new Event("change", { bubbles: true }));
+  50  |   });
+  51  | }
+  52  | 
+  53  | test("two audio elements exist for crossfade", async ({ page }) => {
+  54  |   await boot(page);
+  55  |   const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  56  |   expect(n).toBe(2);
+  57  | });
+  58  | 
+  59  | test("a new volume fade supersedes a stale one (audio not silenced after landing)", async ({ page }) => {
+  60  |   await boot(page);
+  61  |   // Reproduce the race: a fade-to-0 in flight, then the same element is brought back
+  62  |   // up (as happens when a faded idle element becomes the newly-landed active scale).
+  63  |   // The stale fade must NOT drag it back to 0.
+  64  |   const vol = await page.evaluate(async () => {
+  65  |     const a = document.querySelector("#aud") as HTMLAudioElement;
+  66  |     a.volume = 1;
+  67  |     (window as any).__hefFade(a, 0, 600);              // start a slow fade to 0
+  68  |     await new Promise((r) => setTimeout(r, 120));      // let it ramp partway down
+  69  |     (window as any).__hefFade(a, 0.8, 90);             // new fade up — must cancel the old one
+  70  |     await new Promise((r) => setTimeout(r, 350));      // well past both fades
+  71  |     return a.volume;
+  72  |   });
+  73  |   expect(vol).toBeGreaterThan(0.7);                    // ended near 0.8, not dragged to 0
+  74  | });
+  75  | 
+  76  | test("audio is a 0-10 level dial", async ({ page }) => {
+  77  |   await boot(page);
+  78  |   const ctl = await page.evaluate(() => {
+  79  |     const c = document.querySelector("#audio") as HTMLInputElement;
+  80  |     return { type: c.type, min: c.min, max: c.max };
+  81  |   });
+  82  |   expect(ctl.type).toBe("range");
+  83  |   expect(ctl.min).toBe("0");
+  84  |   expect(ctl.max).toBe("10");
+  85  | });
+  86  | 
+  87  | // (Entry via the welcome screen — defaults, Launch, control carry-over, State B —
+  88  | // is covered in welcome.spec.ts.)
+  89  | 
+  90  | test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  91  |   await boot(page);
+  92  |   await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  93  |   const box = (await page.locator("#dial").boundingBox())!;
+  94  |   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  95  |   await page.mouse.move(cx, cy - 30);
+  96  |   await page.mouse.down();
+  97  |   await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  98  |   // The currentTime seek is throttled to one rAF; wait for it to land.
+  99  |   await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  100 |   const state = await page.evaluate(() => ({
+  101 |     t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+  102 |     ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+  103 |     gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  104 |   }));
+  105 |   expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  106 |   expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  107 |   expect(state.ga).toBeLessThan(1);            // current scale fading out
+  108 |   await page.mouse.up();
+  109 | });
+  110 | 
+  111 | test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  112 |   await boot(page);
+  113 |   const start = (await page.locator("#scale-name").textContent())!;
+  114 |   await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  115 |   await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  116 |   const landed = (await page.locator("#scale-name").textContent())!;
+  117 |   expect(landed).toContain("orbit");
+  118 |   await page.waitForTimeout(1500);
+  119 |   expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/i18n-language-dropdown-loc-69a23-resets-to-English-on-reload/error-context.md b/simulator/e2e/test-results/i18n-language-dropdown-loc-69a23-resets-to-English-on-reload/error-context.md
new file mode 100644
index 0000000..c80b047
--- /dev/null
+++ b/simulator/e2e/test-results/i18n-language-dropdown-loc-69a23-resets-to-English-on-reload/error-context.md
@@ -0,0 +1,80 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: i18n.spec.ts >> language dropdown localizes chrome and resets to English on reload
+- Location: tests/i18n.spec.ts:15:5
+
+# Error details
+
+```
+Error: expect(locator).toHaveCount(expected) failed
+
+Locator:  locator('#welcome-lang option')
+Expected: 4
+Received: 0
+Timeout:  5000ms
+
+Call log:
+  - Expect "toHaveCount" with timeout 5000ms
+  - waiting for locator('#welcome-lang option')
+    13 × locator resolved to 0 elements
+       - unexpected value "0"
+
+```
+
+# Page snapshot
+
+```yaml
+- generic [ref=e2]: "{\"detail\":\"Not Found\"}"
+```
+
+# Test source
+
+```ts
+  1  | import { test, expect, Page } from "@playwright/test";
+  2  | 
+  3  | // The language dropdown localizes the visitor-facing chrome live (and resets to
+  4  | // English on reload — selection is session-only, no persistence). Annotation
+  5  | // re-rendering is covered by the unit tests (resolveStrings) + the manifest
+  6  | // invariant test; here we assert the DOM behavior of the dropdown itself.
+  7  | 
+  8  | async function boot(page: Page) {
+  9  |   await page.goto("/");
+  10 |   // initLanguage() populates BOTH selects during startup (before media preload).
+  11 |   // The welcome select is the visible one (the panel is hidden until entry).
+> 12 |   await expect(page.locator("#welcome-lang option")).toHaveCount(4);
+     |                                                      ^ Error: expect(locator).toHaveCount(expected) failed
+  13 | }
+  14 | 
+  15 | test("language dropdown localizes chrome and resets to English on reload", async ({ page }) => {
+  16 |   await boot(page);
+  17 |   const sel = page.locator("#welcome-lang"); // the welcome screen's selector
+  18 | 
+  19 |   // English selected by default (both selects mirror activeLang)
+  20 |   await expect(sel).toHaveValue("en");
+  21 |   await expect(page.locator("#lang-select")).toHaveValue("en");
+  22 |   await expect(page.locator('[data-i18n="output.legend"]')).toHaveText("Output");
+  23 |   await expect(page.locator("html")).toHaveAttribute("lang", "en");
+  24 | 
+  25 |   // switch to Spanish -> chrome changes (incl. the hidden panel), <html lang> updates
+  26 |   await sel.selectOption("es");
+  27 |   await expect(page.locator('[data-i18n="output.legend"]')).toHaveText("Salida");
+  28 |   await expect(page.locator("#lang-select")).toHaveValue("es"); // panel select mirrors
+  29 |   await expect(page.locator("html")).toHaveAttribute("lang", "es");
+  30 | 
+  31 |   // Japanese
+  32 |   await sel.selectOption("ja");
+  33 |   await expect(page.locator('[data-i18n="knobs.think"]')).toHaveText("考える");
+  34 | 
+  35 |   // reload returns to English (session-only, no persistence)
+  36 |   await page.reload();
+  37 |   await expect(page.locator("#welcome-lang")).toHaveValue("en");
+  38 |   await expect(page.locator('[data-i18n="output.legend"]')).toHaveText("Output");
+  39 | });
+  40 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/loop-recovery-loop-recover-556bc-ed-no-freeze-on-last-frame-/error-context.md b/simulator/e2e/test-results/loop-recovery-loop-recover-556bc-ed-no-freeze-on-last-frame-/error-context.md
new file mode 100644
index 0000000..63f3234
--- /dev/null
+++ b/simulator/e2e/test-results/loop-recovery-loop-recover-556bc-ed-no-freeze-on-last-frame-/error-context.md
@@ -0,0 +1,63 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: loop-recovery.spec.ts >> loop recovers when a clip reaches `ended` (no freeze on last frame)
+- Location: tests/loop-recovery.spec.ts:7:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [ref=e2]: "{\"detail\":\"Not Found\"}"
+```
+
+# Test source
+
+```ts
+  1  | import { test, expect } from "@playwright/test";
+  2  | 
+  3  | // Regression: the steady-state loop (#vid-loop) restarts from the morph-tail
+  4  | // offset via a narrow timeupdate window. If that window is ever missed the clip
+  5  | // fires `ended` and — without a safety net — freezes on its last frame ("videos
+  6  | // aren't looping"). This asserts the `ended` safety net recovers playback.
+  7  | test("loop recovers when a clip reaches `ended` (no freeze on last frame)", async ({ page }) => {
+  8  |   await page.goto("/");
+  9  |   // Enter via the welcome screen (Video defaults on → the loop video loads).
+> 10 |   await page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+     |              ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  11 |   await page.locator("#welcome-launch").click();
+  12 |   await page.waitForSelector("#welcome", { state: "detached", timeout: 10_000 });
+  13 |   // Wait for the loop video to actually have media before forcing the stuck state.
+  14 |   await page.waitForFunction(
+  15 |     () => { const v = document.getElementById("vid-loop") as HTMLVideoElement; return v && v.duration > 0; },
+  16 |     null,
+  17 |     { timeout: 20_000 },
+  18 |   );
+  19 | 
+  20 |   const r = await page.evaluate(async () => {
+  21 |     const lv = document.getElementById("vid-loop") as HTMLVideoElement;
+  22 |     // Reproduce the stuck state: parked on the last frame, as after a missed wrap.
+  23 |     lv.pause();
+  24 |     lv.currentTime = Math.max(0, lv.duration - 0.001);
+  25 |     // The browser emits `ended` here in real life; emit it deterministically.
+  26 |     lv.dispatchEvent(new Event("ended"));
+  27 |     await new Promise((res) => setTimeout(res, 800));
+  28 |     return { dur: +lv.duration.toFixed(2), ct: +lv.currentTime.toFixed(2), paused: lv.paused };
+  29 |   });
+  30 | 
+  31 |   // Recovered: playing again, and seeked back near the loop tail (not stuck at end).
+  32 |   expect(r.paused).toBe(false);
+  33 |   expect(r.ct).toBeLessThan(5);
+  34 | });
+  35 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/welcome-Launch-when-alread-e343d-ectly-and-reveals-the-panel/error-context.md b/simulator/e2e/test-results/welcome-Launch-when-alread-e343d-ectly-and-reveals-the-panel/error-context.md
new file mode 100644
index 0000000..ee68697
--- /dev/null
+++ b/simulator/e2e/test-results/welcome-Launch-when-alread-e343d-ectly-and-reveals-the-panel/error-context.md
@@ -0,0 +1,138 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: welcome.spec.ts >> Launch when already loaded enters the simulation directly and reveals the panel
+- Location: tests/welcome.spec.ts:61:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [ref=e2]: "{\"detail\":\"Not Found\"}"
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // The Welcome screen is the universal entry gate (see
+  4   | // docs/superpowers/specs/2026-06-30-welcome-screen-design.md). It carries the
+  5   | // photosensitivity heads-up, the four output controls (Video on / Reduce motion
+  6   | // off / Audio 2 / English), a "Launch Simulator" button, and the "Loading
+  7   | // Universe" progress. The right panel is hidden until the visitor enters.
+  8   | 
+  9   | const ready = (page: Page) =>
+> 10  |   page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |        ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  11  | 
+  12  | // Set a range input's value + fire `input` (Playwright's fill() doesn't drive ranges).
+  13  | async function setRange(page: Page, id: string, value: string) {
+  14  |   await page.evaluate(({ id, value }) => {
+  15  |     const el = document.getElementById(id) as HTMLInputElement;
+  16  |     el.value = value;
+  17  |     el.dispatchEvent(new Event("input", { bubbles: true }));
+  18  |   }, { id, value });
+  19  | }
+  20  | 
+  21  | test("welcome screen shows on load with the expected defaults; the panel is hidden", async ({ page }) => {
+  22  |   await page.emulateMedia({ reducedMotion: "no-preference" });
+  23  |   await page.goto("/");
+  24  | 
+  25  |   await expect(page.locator("#welcome")).toBeVisible();
+  26  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  27  | 
+  28  |   // Defaults: Language English, Speed 1, Audio 2.
+  29  |   await expect(page.locator("#welcome-lang")).toHaveValue("en");
+  30  |   await expect(page.locator("#welcome-play-speed")).toHaveValue("1");
+  31  |   await expect(page.locator("#welcome-play-speed-val")).toHaveText("1.00×");
+  32  |   await expect(page.locator("#welcome-audio")).toHaveValue("2");
+  33  |   await expect(page.locator("#welcome-audio-val")).toHaveText("2");
+  34  | 
+  35  |   // Heads-up + Launch button present; "Loading Universe" progress present.
+  36  |   await expect(page.locator("#welcome-title")).toBeVisible();
+  37  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  38  |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  39  | 
+  40  |   // The right panel is hidden behind the welcome screen.
+  41  |   await expect(page.locator(".panel")).toBeHidden();
+  42  | });
+  43  | 
+  44  | test("the language picker re-renders the welcome text live", async ({ page }) => {
+  45  |   await page.goto("/");
+  46  |   const sel = page.locator("#welcome-lang");
+  47  |   await expect(sel).toHaveValue("en");
+  48  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  49  | 
+  50  |   await sel.selectOption("es");
+  51  |   await expect(page.locator("#welcome-launch")).toHaveText("Iniciar simulador");
+  52  |   await expect(page.locator("#welcome-title")).toHaveText(/Atención/);
+  53  |   await expect(page.locator("html")).toHaveAttribute("lang", "es");
+  54  |   // the hidden panel selector mirrors the choice
+  55  |   await expect(page.locator("#lang-select")).toHaveValue("es");
+  56  | 
+  57  |   await sel.selectOption("ja");
+  58  |   await expect(page.locator("#welcome-launch")).toHaveText("シミュレーターを起動");
+  59  | });
+  60  | 
+  61  | test("Launch when already loaded enters the simulation directly and reveals the panel", async ({ page }) => {
+  62  |   await page.goto("/");
+  63  |   await ready(page);
+  64  | 
+  65  |   await page.locator("#welcome-launch").click();
+  66  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  67  |   await expect(page.locator(".panel")).toBeVisible();
+  68  | 
+  69  |   // Welcome assumes Video on; Audio default 2 carried into the panel.
+  70  |   await expect(page.locator("#visual")).toBeChecked();
+  71  |   await expect(page.locator("#audio")).toHaveValue("2");
+  72  | });
+  73  | 
+  74  | test("welcome control values carry into the panel on entry", async ({ page }) => {
+  75  |   await page.goto("/");
+  76  |   await ready(page);
+  77  | 
+  78  |   await setRange(page, "welcome-audio", "5");
+  79  |   await setRange(page, "welcome-play-speed", "2"); // mirrors into the panel slider live
+  80  |   await page.locator("#welcome-launch").click();
+  81  | 
+  82  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  83  |   await expect(page.locator("#audio")).toHaveValue("5");
+  84  |   await expect(page.locator("#play-speed")).toHaveValue("2");
+  85  |   await expect(page.locator("#visual")).toBeChecked(); // welcome assumes video on
+  86  | });
+  87  | 
+  88  | test("Launch while still loading shows the centered loader with controls, then auto-enters", async ({ page }) => {
+  89  |   // Stall media so phase-1 preload hasn't finished when Launch is pressed.
+  90  |   let release!: () => void;
+  91  |   const gate = new Promise<void>((r) => (release = r));
+  92  |   await page.route("**/media/**", async (route) => {
+  93  |     await gate;
+  94  |     await route.continue();
+  95  |   });
+  96  | 
+  97  |   await page.goto("/");
+  98  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  99  | 
+  100 |   await page.locator("#welcome-launch").click();
+  101 | 
+  102 |   // State B: messaging + button hidden, controls remain, loader shown (centered).
+  103 |   await expect(page.locator("#welcome")).toHaveClass(/loading/);
+  104 |   await expect(page.locator("#welcome-title")).toBeHidden();
+  105 |   await expect(page.locator("#welcome-launch")).toBeHidden();
+  106 |   await expect(page.locator(".welcome-controls")).toBeVisible();
+  107 |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  108 | 
+  109 |   // Let media through → universe becomes ready → auto-enter.
+  110 |   release();
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/welcome-Launch-while-still-51a6a-h-controls-then-auto-enters/error-context.md b/simulator/e2e/test-results/welcome-Launch-while-still-51a6a-h-controls-then-auto-enters/error-context.md
new file mode 100644
index 0000000..1e23aaa
--- /dev/null
+++ b/simulator/e2e/test-results/welcome-Launch-while-still-51a6a-h-controls-then-auto-enters/error-context.md
@@ -0,0 +1,192 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: welcome.spec.ts >> Launch while still loading shows the centered loader with controls, then auto-enters
+- Location: tests/welcome.spec.ts:88:5
+
+# Error details
+
+```
+Error: expect(locator).toHaveClass(expected) failed
+
+Locator: locator('#welcome')
+Expected pattern: /welcoming/
+Timeout: 5000ms
+Error: element(s) not found
+
+Call log:
+  - Expect "toHaveClass" with timeout 5000ms
+  - waiting for locator('#welcome')
+
+```
+
+```yaml
+- text: Loading Universe...
+- banner:
+  - heading "Human Experience Filter — Alteration Preview" [level=1]
+  - link "About":
+    - /url: about.html
+  - link "ⓘ Credits & licenses":
+    - /url: credits.html
+- main:
+  - status: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+  - group "Output":
+    - text: Output
+    - checkbox "Video"
+    - text: Video Audio
+    - slider "Audio 0 /10": "0"
+    - text: 0 /10 Speed
+    - slider "Speed 1.00×": "1"
+    - text: 1.00× 🌐
+    - combobox "Language":
+      - option "English" [selected]
+      - option "Español"
+      - option "Français"
+      - option "日本語"
+  - group "Altitude":
+    - text: Altitude
+    - slider "Altitude — turn or use arrow keys to change scale":
+      - button "cosmos"
+      - button "orbit"
+      - button "sky"
+      - button "coast"
+      - button "reef"
+      - button "abyss"
+      - text: ALTITUDE
+    - text: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+    - paragraph: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+  - group "Experience knobs (0–4)":
+    - text: Experience knobs (0–4) Think
+    - slider "Think": "0"
+    - text: Feel
+    - slider "Feel": "0"
+    - text: Mood — dark ◀ 0 ▶ light
+    - slider "Mood — dark ◀ 0 ▶ light": "0"
+  - checkbox "Dev Mode"
+  - text: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // The Welcome screen is the universal entry gate (see
+  4   | // docs/superpowers/specs/2026-06-30-welcome-screen-design.md). It carries the
+  5   | // photosensitivity heads-up, the four output controls (Video on / Reduce motion
+  6   | // off / Audio 2 / English), a "Launch Simulator" button, and the "Loading
+  7   | // Universe" progress. The right panel is hidden until the visitor enters.
+  8   | 
+  9   | const ready = (page: Page) =>
+  10  |   page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+  11  | 
+  12  | // Set a range input's value + fire `input` (Playwright's fill() doesn't drive ranges).
+  13  | async function setRange(page: Page, id: string, value: string) {
+  14  |   await page.evaluate(({ id, value }) => {
+  15  |     const el = document.getElementById(id) as HTMLInputElement;
+  16  |     el.value = value;
+  17  |     el.dispatchEvent(new Event("input", { bubbles: true }));
+  18  |   }, { id, value });
+  19  | }
+  20  | 
+  21  | test("welcome screen shows on load with the expected defaults; the panel is hidden", async ({ page }) => {
+  22  |   await page.emulateMedia({ reducedMotion: "no-preference" });
+  23  |   await page.goto("/");
+  24  | 
+  25  |   await expect(page.locator("#welcome")).toBeVisible();
+  26  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  27  | 
+  28  |   // Defaults: Language English, Speed 1, Audio 2.
+  29  |   await expect(page.locator("#welcome-lang")).toHaveValue("en");
+  30  |   await expect(page.locator("#welcome-play-speed")).toHaveValue("1");
+  31  |   await expect(page.locator("#welcome-play-speed-val")).toHaveText("1.00×");
+  32  |   await expect(page.locator("#welcome-audio")).toHaveValue("2");
+  33  |   await expect(page.locator("#welcome-audio-val")).toHaveText("2");
+  34  | 
+  35  |   // Heads-up + Launch button present; "Loading Universe" progress present.
+  36  |   await expect(page.locator("#welcome-title")).toBeVisible();
+  37  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  38  |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  39  | 
+  40  |   // The right panel is hidden behind the welcome screen.
+  41  |   await expect(page.locator(".panel")).toBeHidden();
+  42  | });
+  43  | 
+  44  | test("the language picker re-renders the welcome text live", async ({ page }) => {
+  45  |   await page.goto("/");
+  46  |   const sel = page.locator("#welcome-lang");
+  47  |   await expect(sel).toHaveValue("en");
+  48  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  49  | 
+  50  |   await sel.selectOption("es");
+  51  |   await expect(page.locator("#welcome-launch")).toHaveText("Iniciar simulador");
+  52  |   await expect(page.locator("#welcome-title")).toHaveText(/Atención/);
+  53  |   await expect(page.locator("html")).toHaveAttribute("lang", "es");
+  54  |   // the hidden panel selector mirrors the choice
+  55  |   await expect(page.locator("#lang-select")).toHaveValue("es");
+  56  | 
+  57  |   await sel.selectOption("ja");
+  58  |   await expect(page.locator("#welcome-launch")).toHaveText("シミュレーターを起動");
+  59  | });
+  60  | 
+  61  | test("Launch when already loaded enters the simulation directly and reveals the panel", async ({ page }) => {
+  62  |   await page.goto("/");
+  63  |   await ready(page);
+  64  | 
+  65  |   await page.locator("#welcome-launch").click();
+  66  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  67  |   await expect(page.locator(".panel")).toBeVisible();
+  68  | 
+  69  |   // Welcome assumes Video on; Audio default 2 carried into the panel.
+  70  |   await expect(page.locator("#visual")).toBeChecked();
+  71  |   await expect(page.locator("#audio")).toHaveValue("2");
+  72  | });
+  73  | 
+  74  | test("welcome control values carry into the panel on entry", async ({ page }) => {
+  75  |   await page.goto("/");
+  76  |   await ready(page);
+  77  | 
+  78  |   await setRange(page, "welcome-audio", "5");
+  79  |   await setRange(page, "welcome-play-speed", "2"); // mirrors into the panel slider live
+  80  |   await page.locator("#welcome-launch").click();
+  81  | 
+  82  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  83  |   await expect(page.locator("#audio")).toHaveValue("5");
+  84  |   await expect(page.locator("#play-speed")).toHaveValue("2");
+  85  |   await expect(page.locator("#visual")).toBeChecked(); // welcome assumes video on
+  86  | });
+  87  | 
+  88  | test("Launch while still loading shows the centered loader with controls, then auto-enters", async ({ page }) => {
+  89  |   // Stall media so phase-1 preload hasn't finished when Launch is pressed.
+  90  |   let release!: () => void;
+  91  |   const gate = new Promise<void>((r) => (release = r));
+  92  |   await page.route("**/media/**", async (route) => {
+  93  |     await gate;
+  94  |     await route.continue();
+  95  |   });
+  96  | 
+  97  |   await page.goto("/");
+> 98  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+      |                                          ^ Error: expect(locator).toHaveClass(expected) failed
+  99  | 
+  100 |   await page.locator("#welcome-launch").click();
+  101 | 
+  102 |   // State B: messaging + button hidden, controls remain, loader shown (centered).
+  103 |   await expect(page.locator("#welcome")).toHaveClass(/loading/);
+  104 |   await expect(page.locator("#welcome-title")).toBeHidden();
+  105 |   await expect(page.locator("#welcome-launch")).toBeHidden();
+  106 |   await expect(page.locator(".welcome-controls")).toBeVisible();
+  107 |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  108 | 
+  109 |   // Let media through → universe becomes ready → auto-enter.
+  110 |   release();
+  111 |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 30_000 });
+  112 |   await expect(page.locator(".panel")).toBeVisible();
+  113 | });
+  114 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/welcome-the-language-picker-re-renders-the-welcome-text-live/error-context.md b/simulator/e2e/test-results/welcome-the-language-picker-re-renders-the-welcome-text-live/error-context.md
new file mode 100644
index 0000000..a4ef302
--- /dev/null
+++ b/simulator/e2e/test-results/welcome-the-language-picker-re-renders-the-welcome-text-live/error-context.md
@@ -0,0 +1,150 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: welcome.spec.ts >> the language picker re-renders the welcome text live
+- Location: tests/welcome.spec.ts:44:5
+
+# Error details
+
+```
+Error: expect(locator).toHaveValue(expected) failed
+
+Locator: locator('#welcome-lang')
+Expected: "en"
+Timeout: 5000ms
+Error: element(s) not found
+
+Call log:
+  - Expect "toHaveValue" with timeout 5000ms
+  - waiting for locator('#welcome-lang')
+
+```
+
+```yaml
+- text: "{\"detail\":\"Not Found\"}"
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // The Welcome screen is the universal entry gate (see
+  4   | // docs/superpowers/specs/2026-06-30-welcome-screen-design.md). It carries the
+  5   | // photosensitivity heads-up, the four output controls (Video on / Reduce motion
+  6   | // off / Audio 2 / English), a "Launch Simulator" button, and the "Loading
+  7   | // Universe" progress. The right panel is hidden until the visitor enters.
+  8   | 
+  9   | const ready = (page: Page) =>
+  10  |   page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+  11  | 
+  12  | // Set a range input's value + fire `input` (Playwright's fill() doesn't drive ranges).
+  13  | async function setRange(page: Page, id: string, value: string) {
+  14  |   await page.evaluate(({ id, value }) => {
+  15  |     const el = document.getElementById(id) as HTMLInputElement;
+  16  |     el.value = value;
+  17  |     el.dispatchEvent(new Event("input", { bubbles: true }));
+  18  |   }, { id, value });
+  19  | }
+  20  | 
+  21  | test("welcome screen shows on load with the expected defaults; the panel is hidden", async ({ page }) => {
+  22  |   await page.emulateMedia({ reducedMotion: "no-preference" });
+  23  |   await page.goto("/");
+  24  | 
+  25  |   await expect(page.locator("#welcome")).toBeVisible();
+  26  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  27  | 
+  28  |   // Defaults: Language English, Speed 1, Audio 2.
+  29  |   await expect(page.locator("#welcome-lang")).toHaveValue("en");
+  30  |   await expect(page.locator("#welcome-play-speed")).toHaveValue("1");
+  31  |   await expect(page.locator("#welcome-play-speed-val")).toHaveText("1.00×");
+  32  |   await expect(page.locator("#welcome-audio")).toHaveValue("2");
+  33  |   await expect(page.locator("#welcome-audio-val")).toHaveText("2");
+  34  | 
+  35  |   // Heads-up + Launch button present; "Loading Universe" progress present.
+  36  |   await expect(page.locator("#welcome-title")).toBeVisible();
+  37  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  38  |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  39  | 
+  40  |   // The right panel is hidden behind the welcome screen.
+  41  |   await expect(page.locator(".panel")).toBeHidden();
+  42  | });
+  43  | 
+  44  | test("the language picker re-renders the welcome text live", async ({ page }) => {
+  45  |   await page.goto("/");
+  46  |   const sel = page.locator("#welcome-lang");
+> 47  |   await expect(sel).toHaveValue("en");
+      |                     ^ Error: expect(locator).toHaveValue(expected) failed
+  48  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  49  | 
+  50  |   await sel.selectOption("es");
+  51  |   await expect(page.locator("#welcome-launch")).toHaveText("Iniciar simulador");
+  52  |   await expect(page.locator("#welcome-title")).toHaveText(/Atención/);
+  53  |   await expect(page.locator("html")).toHaveAttribute("lang", "es");
+  54  |   // the hidden panel selector mirrors the choice
+  55  |   await expect(page.locator("#lang-select")).toHaveValue("es");
+  56  | 
+  57  |   await sel.selectOption("ja");
+  58  |   await expect(page.locator("#welcome-launch")).toHaveText("シミュレーターを起動");
+  59  | });
+  60  | 
+  61  | test("Launch when already loaded enters the simulation directly and reveals the panel", async ({ page }) => {
+  62  |   await page.goto("/");
+  63  |   await ready(page);
+  64  | 
+  65  |   await page.locator("#welcome-launch").click();
+  66  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  67  |   await expect(page.locator(".panel")).toBeVisible();
+  68  | 
+  69  |   // Welcome assumes Video on; Audio default 2 carried into the panel.
+  70  |   await expect(page.locator("#visual")).toBeChecked();
+  71  |   await expect(page.locator("#audio")).toHaveValue("2");
+  72  | });
+  73  | 
+  74  | test("welcome control values carry into the panel on entry", async ({ page }) => {
+  75  |   await page.goto("/");
+  76  |   await ready(page);
+  77  | 
+  78  |   await setRange(page, "welcome-audio", "5");
+  79  |   await setRange(page, "welcome-play-speed", "2"); // mirrors into the panel slider live
+  80  |   await page.locator("#welcome-launch").click();
+  81  | 
+  82  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  83  |   await expect(page.locator("#audio")).toHaveValue("5");
+  84  |   await expect(page.locator("#play-speed")).toHaveValue("2");
+  85  |   await expect(page.locator("#visual")).toBeChecked(); // welcome assumes video on
+  86  | });
+  87  | 
+  88  | test("Launch while still loading shows the centered loader with controls, then auto-enters", async ({ page }) => {
+  89  |   // Stall media so phase-1 preload hasn't finished when Launch is pressed.
+  90  |   let release!: () => void;
+  91  |   const gate = new Promise<void>((r) => (release = r));
+  92  |   await page.route("**/media/**", async (route) => {
+  93  |     await gate;
+  94  |     await route.continue();
+  95  |   });
+  96  | 
+  97  |   await page.goto("/");
+  98  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  99  | 
+  100 |   await page.locator("#welcome-launch").click();
+  101 | 
+  102 |   // State B: messaging + button hidden, controls remain, loader shown (centered).
+  103 |   await expect(page.locator("#welcome")).toHaveClass(/loading/);
+  104 |   await expect(page.locator("#welcome-title")).toBeHidden();
+  105 |   await expect(page.locator("#welcome-launch")).toBeHidden();
+  106 |   await expect(page.locator(".welcome-controls")).toBeVisible();
+  107 |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  108 | 
+  109 |   // Let media through → universe becomes ready → auto-enter.
+  110 |   release();
+  111 |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 30_000 });
+  112 |   await expect(page.locator(".panel")).toBeVisible();
+  113 | });
+  114 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/welcome-welcome-control-values-carry-into-the-panel-on-entry/error-context.md b/simulator/e2e/test-results/welcome-welcome-control-values-carry-into-the-panel-on-entry/error-context.md
new file mode 100644
index 0000000..e659a27
--- /dev/null
+++ b/simulator/e2e/test-results/welcome-welcome-control-values-carry-into-the-panel-on-entry/error-context.md
@@ -0,0 +1,203 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: welcome.spec.ts >> welcome control values carry into the panel on entry
+- Location: tests/welcome.spec.ts:74:5
+
+# Error details
+
+```
+TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+```
+
+# Page snapshot
+
+```yaml
+- generic [active] [ref=e1]:
+  - banner [ref=e2]:
+    - heading "Human Experience Filter — Alteration Preview" [level=1] [ref=e3]
+    - link "About" [ref=e4] [cursor=pointer]:
+      - /url: about.html
+    - link "ⓘ Credits & licenses" [ref=e5] [cursor=pointer]:
+      - /url: credits.html
+  - main [ref=e6]:
+    - generic [ref=e8]:
+      - img
+      - img
+      - button "Run simulation" [ref=e12] [cursor=pointer]
+      - dialog "Heads up — motion & flashing" [ref=e13]:
+        - generic [ref=e14]:
+          - heading "Heads up — motion & flashing" [level=2] [ref=e15]
+          - paragraph [ref=e16]: This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you begin — the experience honours it automatically.
+          - button "Continue" [ref=e17] [cursor=pointer]
+    - generic [ref=e18]:
+      - status [ref=e19]: cosmos. Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI)
+      - group "Output" [ref=e20]:
+        - generic [ref=e21]: Output
+        - generic [ref=e22] [cursor=pointer]:
+          - checkbox "Video"
+          - generic [ref=e25]: Video
+        - generic [ref=e26]:
+          - generic [ref=e27]: Audio
+          - slider "Audio 0 /10" [ref=e28]: "0"
+          - generic [ref=e29]: "0"
+          - text: /10
+        - generic [ref=e30]:
+          - generic [ref=e31]: Speed
+          - slider "Speed 1.00×" [ref=e32]: "1"
+          - generic [ref=e33]: 1.00×
+        - generic [ref=e34]:
+          - text: 🌐
+          - combobox "Language" [ref=e35]:
+            - option "English" [selected]
+            - option "Español"
+            - option "Français"
+            - option "日本語"
+      - group "Altitude" [ref=e36]:
+        - generic [ref=e37]: Altitude
+        - slider "Altitude — turn or use arrow keys to change scale" [ref=e39]:
+          - button "cosmos" [ref=e42] [cursor=pointer]
+          - button "orbit" [ref=e44] [cursor=pointer]
+          - button "sky" [ref=e46] [cursor=pointer]
+          - button "coast" [ref=e47] [cursor=pointer]
+          - button "reef" [ref=e49] [cursor=pointer]
+          - button "abyss" [ref=e51] [cursor=pointer]
+          - generic [ref=e52]: ALTITUDE
+        - generic [ref=e56]: cosmos · Cosmic Cliffs — Carina Nebula flythrough (NASA/ESA/CSA/STScI) (1/6 · pool 7)
+        - paragraph [ref=e57]: "Turn the knob (drag it, or scroll) to change altitude — endless: past the deepest it wraps back up to the highest. Click a label to jump there."
+      - group "Experience knobs (0–4)" [ref=e58]:
+        - generic [ref=e59]: Experience knobs (0–4)
+        - generic [ref=e60]:
+          - text: Think
+          - slider "Think" [ref=e61]: "0"
+        - generic [ref=e62]:
+          - text: Feel
+          - slider "Feel" [ref=e63]: "0"
+        - generic [ref=e64]:
+          - text: Mood — dark ◀ 0 ▶ light
+          - slider "Mood — dark ◀ 0 ▶ light" [ref=e65]: "0"
+      - generic [ref=e66] [cursor=pointer]:
+        - checkbox "Dev Mode"
+        - generic [ref=e69]: Dev Mode
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // The Welcome screen is the universal entry gate (see
+  4   | // docs/superpowers/specs/2026-06-30-welcome-screen-design.md). It carries the
+  5   | // photosensitivity heads-up, the four output controls (Video on / Reduce motion
+  6   | // off / Audio 2 / English), a "Launch Simulator" button, and the "Loading
+  7   | // Universe" progress. The right panel is hidden until the visitor enters.
+  8   | 
+  9   | const ready = (page: Page) =>
+> 10  |   page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+      |        ^ TimeoutError: page.waitForFunction: Timeout 45000ms exceeded.
+  11  | 
+  12  | // Set a range input's value + fire `input` (Playwright's fill() doesn't drive ranges).
+  13  | async function setRange(page: Page, id: string, value: string) {
+  14  |   await page.evaluate(({ id, value }) => {
+  15  |     const el = document.getElementById(id) as HTMLInputElement;
+  16  |     el.value = value;
+  17  |     el.dispatchEvent(new Event("input", { bubbles: true }));
+  18  |   }, { id, value });
+  19  | }
+  20  | 
+  21  | test("welcome screen shows on load with the expected defaults; the panel is hidden", async ({ page }) => {
+  22  |   await page.emulateMedia({ reducedMotion: "no-preference" });
+  23  |   await page.goto("/");
+  24  | 
+  25  |   await expect(page.locator("#welcome")).toBeVisible();
+  26  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  27  | 
+  28  |   // Defaults: Language English, Speed 1, Audio 2.
+  29  |   await expect(page.locator("#welcome-lang")).toHaveValue("en");
+  30  |   await expect(page.locator("#welcome-play-speed")).toHaveValue("1");
+  31  |   await expect(page.locator("#welcome-play-speed-val")).toHaveText("1.00×");
+  32  |   await expect(page.locator("#welcome-audio")).toHaveValue("2");
+  33  |   await expect(page.locator("#welcome-audio-val")).toHaveText("2");
+  34  | 
+  35  |   // Heads-up + Launch button present; "Loading Universe" progress present.
+  36  |   await expect(page.locator("#welcome-title")).toBeVisible();
+  37  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  38  |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  39  | 
+  40  |   // The right panel is hidden behind the welcome screen.
+  41  |   await expect(page.locator(".panel")).toBeHidden();
+  42  | });
+  43  | 
+  44  | test("the language picker re-renders the welcome text live", async ({ page }) => {
+  45  |   await page.goto("/");
+  46  |   const sel = page.locator("#welcome-lang");
+  47  |   await expect(sel).toHaveValue("en");
+  48  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  49  | 
+  50  |   await sel.selectOption("es");
+  51  |   await expect(page.locator("#welcome-launch")).toHaveText("Iniciar simulador");
+  52  |   await expect(page.locator("#welcome-title")).toHaveText(/Atención/);
+  53  |   await expect(page.locator("html")).toHaveAttribute("lang", "es");
+  54  |   // the hidden panel selector mirrors the choice
+  55  |   await expect(page.locator("#lang-select")).toHaveValue("es");
+  56  | 
+  57  |   await sel.selectOption("ja");
+  58  |   await expect(page.locator("#welcome-launch")).toHaveText("シミュレーターを起動");
+  59  | });
+  60  | 
+  61  | test("Launch when already loaded enters the simulation directly and reveals the panel", async ({ page }) => {
+  62  |   await page.goto("/");
+  63  |   await ready(page);
+  64  | 
+  65  |   await page.locator("#welcome-launch").click();
+  66  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  67  |   await expect(page.locator(".panel")).toBeVisible();
+  68  | 
+  69  |   // Welcome assumes Video on; Audio default 2 carried into the panel.
+  70  |   await expect(page.locator("#visual")).toBeChecked();
+  71  |   await expect(page.locator("#audio")).toHaveValue("2");
+  72  | });
+  73  | 
+  74  | test("welcome control values carry into the panel on entry", async ({ page }) => {
+  75  |   await page.goto("/");
+  76  |   await ready(page);
+  77  | 
+  78  |   await setRange(page, "welcome-audio", "5");
+  79  |   await setRange(page, "welcome-play-speed", "2"); // mirrors into the panel slider live
+  80  |   await page.locator("#welcome-launch").click();
+  81  | 
+  82  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  83  |   await expect(page.locator("#audio")).toHaveValue("5");
+  84  |   await expect(page.locator("#play-speed")).toHaveValue("2");
+  85  |   await expect(page.locator("#visual")).toBeChecked(); // welcome assumes video on
+  86  | });
+  87  | 
+  88  | test("Launch while still loading shows the centered loader with controls, then auto-enters", async ({ page }) => {
+  89  |   // Stall media so phase-1 preload hasn't finished when Launch is pressed.
+  90  |   let release!: () => void;
+  91  |   const gate = new Promise<void>((r) => (release = r));
+  92  |   await page.route("**/media/**", async (route) => {
+  93  |     await gate;
+  94  |     await route.continue();
+  95  |   });
+  96  | 
+  97  |   await page.goto("/");
+  98  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  99  | 
+  100 |   await page.locator("#welcome-launch").click();
+  101 | 
+  102 |   // State B: messaging + button hidden, controls remain, loader shown (centered).
+  103 |   await expect(page.locator("#welcome")).toHaveClass(/loading/);
+  104 |   await expect(page.locator("#welcome-title")).toBeHidden();
+  105 |   await expect(page.locator("#welcome-launch")).toBeHidden();
+  106 |   await expect(page.locator(".welcome-controls")).toBeVisible();
+  107 |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  108 | 
+  109 |   // Let media through → universe becomes ready → auto-enter.
+  110 |   release();
+```
\ No newline at end of file
diff --git a/simulator/e2e/test-results/welcome-welcome-screen-sho-74d80-efaults-the-panel-is-hidden/error-context.md b/simulator/e2e/test-results/welcome-welcome-screen-sho-74d80-efaults-the-panel-is-hidden/error-context.md
new file mode 100644
index 0000000..934372a
--- /dev/null
+++ b/simulator/e2e/test-results/welcome-welcome-screen-sho-74d80-efaults-the-panel-is-hidden/error-context.md
@@ -0,0 +1,150 @@
+# Instructions
+
+- Following Playwright test failed.
+- Explain why, be concise, respect Playwright best practices.
+- Provide a snippet of code with the fix, if possible.
+
+# Test info
+
+- Name: welcome.spec.ts >> welcome screen shows on load with the expected defaults; the panel is hidden
+- Location: tests/welcome.spec.ts:21:5
+
+# Error details
+
+```
+Error: expect(locator).toBeVisible() failed
+
+Locator: locator('#welcome')
+Expected: visible
+Timeout: 5000ms
+Error: element(s) not found
+
+Call log:
+  - Expect "toBeVisible" with timeout 5000ms
+  - waiting for locator('#welcome')
+
+```
+
+```yaml
+- text: "{\"detail\":\"Not Found\"}"
+```
+
+# Test source
+
+```ts
+  1   | import { test, expect, Page } from "@playwright/test";
+  2   | 
+  3   | // The Welcome screen is the universal entry gate (see
+  4   | // docs/superpowers/specs/2026-06-30-welcome-screen-design.md). It carries the
+  5   | // photosensitivity heads-up, the four output controls (Video on / Reduce motion
+  6   | // off / Audio 2 / English), a "Launch Simulator" button, and the "Loading
+  7   | // Universe" progress. The right panel is hidden until the visitor enters.
+  8   | 
+  9   | const ready = (page: Page) =>
+  10  |   page.waitForFunction(() => (window as any).__hefReady === true, null, { timeout: 45_000 });
+  11  | 
+  12  | // Set a range input's value + fire `input` (Playwright's fill() doesn't drive ranges).
+  13  | async function setRange(page: Page, id: string, value: string) {
+  14  |   await page.evaluate(({ id, value }) => {
+  15  |     const el = document.getElementById(id) as HTMLInputElement;
+  16  |     el.value = value;
+  17  |     el.dispatchEvent(new Event("input", { bubbles: true }));
+  18  |   }, { id, value });
+  19  | }
+  20  | 
+  21  | test("welcome screen shows on load with the expected defaults; the panel is hidden", async ({ page }) => {
+  22  |   await page.emulateMedia({ reducedMotion: "no-preference" });
+  23  |   await page.goto("/");
+  24  | 
+> 25  |   await expect(page.locator("#welcome")).toBeVisible();
+      |                                          ^ Error: expect(locator).toBeVisible() failed
+  26  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  27  | 
+  28  |   // Defaults: Language English, Speed 1, Audio 2.
+  29  |   await expect(page.locator("#welcome-lang")).toHaveValue("en");
+  30  |   await expect(page.locator("#welcome-play-speed")).toHaveValue("1");
+  31  |   await expect(page.locator("#welcome-play-speed-val")).toHaveText("1.00×");
+  32  |   await expect(page.locator("#welcome-audio")).toHaveValue("2");
+  33  |   await expect(page.locator("#welcome-audio-val")).toHaveText("2");
+  34  | 
+  35  |   // Heads-up + Launch button present; "Loading Universe" progress present.
+  36  |   await expect(page.locator("#welcome-title")).toBeVisible();
+  37  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  38  |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  39  | 
+  40  |   // The right panel is hidden behind the welcome screen.
+  41  |   await expect(page.locator(".panel")).toBeHidden();
+  42  | });
+  43  | 
+  44  | test("the language picker re-renders the welcome text live", async ({ page }) => {
+  45  |   await page.goto("/");
+  46  |   const sel = page.locator("#welcome-lang");
+  47  |   await expect(sel).toHaveValue("en");
+  48  |   await expect(page.locator("#welcome-launch")).toHaveText("Launch Simulator");
+  49  | 
+  50  |   await sel.selectOption("es");
+  51  |   await expect(page.locator("#welcome-launch")).toHaveText("Iniciar simulador");
+  52  |   await expect(page.locator("#welcome-title")).toHaveText(/Atención/);
+  53  |   await expect(page.locator("html")).toHaveAttribute("lang", "es");
+  54  |   // the hidden panel selector mirrors the choice
+  55  |   await expect(page.locator("#lang-select")).toHaveValue("es");
+  56  | 
+  57  |   await sel.selectOption("ja");
+  58  |   await expect(page.locator("#welcome-launch")).toHaveText("シミュレーターを起動");
+  59  | });
+  60  | 
+  61  | test("Launch when already loaded enters the simulation directly and reveals the panel", async ({ page }) => {
+  62  |   await page.goto("/");
+  63  |   await ready(page);
+  64  | 
+  65  |   await page.locator("#welcome-launch").click();
+  66  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  67  |   await expect(page.locator(".panel")).toBeVisible();
+  68  | 
+  69  |   // Welcome assumes Video on; Audio default 2 carried into the panel.
+  70  |   await expect(page.locator("#visual")).toBeChecked();
+  71  |   await expect(page.locator("#audio")).toHaveValue("2");
+  72  | });
+  73  | 
+  74  | test("welcome control values carry into the panel on entry", async ({ page }) => {
+  75  |   await page.goto("/");
+  76  |   await ready(page);
+  77  | 
+  78  |   await setRange(page, "welcome-audio", "5");
+  79  |   await setRange(page, "welcome-play-speed", "2"); // mirrors into the panel slider live
+  80  |   await page.locator("#welcome-launch").click();
+  81  | 
+  82  |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
+  83  |   await expect(page.locator("#audio")).toHaveValue("5");
+  84  |   await expect(page.locator("#play-speed")).toHaveValue("2");
+  85  |   await expect(page.locator("#visual")).toBeChecked(); // welcome assumes video on
+  86  | });
+  87  | 
+  88  | test("Launch while still loading shows the centered loader with controls, then auto-enters", async ({ page }) => {
+  89  |   // Stall media so phase-1 preload hasn't finished when Launch is pressed.
+  90  |   let release!: () => void;
+  91  |   const gate = new Promise<void>((r) => (release = r));
+  92  |   await page.route("**/media/**", async (route) => {
+  93  |     await gate;
+  94  |     await route.continue();
+  95  |   });
+  96  | 
+  97  |   await page.goto("/");
+  98  |   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
+  99  | 
+  100 |   await page.locator("#welcome-launch").click();
+  101 | 
+  102 |   // State B: messaging + button hidden, controls remain, loader shown (centered).
+  103 |   await expect(page.locator("#welcome")).toHaveClass(/loading/);
+  104 |   await expect(page.locator("#welcome-title")).toBeHidden();
+  105 |   await expect(page.locator("#welcome-launch")).toBeHidden();
+  106 |   await expect(page.locator(".welcome-controls")).toBeVisible();
+  107 |   await expect(page.locator(".welcome-loading")).toBeVisible();
+  108 | 
+  109 |   // Let media through → universe becomes ready → auto-enter.
+  110 |   release();
+  111 |   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 30_000 });
+  112 |   await expect(page.locator(".panel")).toBeVisible();
+  113 | });
+  114 | 
+```
\ No newline at end of file
diff --git a/simulator/e2e/tests/a11y.spec.ts b/simulator/e2e/tests/a11y.spec.ts
index 43a21a9..533e5f7 100644
--- a/simulator/e2e/tests/a11y.spec.ts
+++ b/simulator/e2e/tests/a11y.spec.ts
@@ -37,34 +37,73 @@ test.describe("Task 1 — Output panel layout", () => {
 });
 
 test.describe("Task 4 — Photosensitivity notice", () => {
-  test("the welcome screen carries the heads-up notice and a Reduce-motion control", async ({ page }) => {
+  test("the welcome screen carries the heads-up notice and the Speed control", async ({ page }) => {
     await page.goto("/");
     // The heads-up is shown on the welcome screen itself (it is the entry gate).
     await expect(page.locator("#welcome-title")).toBeVisible();
     await expect(page.locator("#welcome-title")).toHaveText(/motion|flashing/i);
-    // The Reduce-motion control sits right there, before the visitor launches.
-    // (The checkbox itself is the visually-hidden pattern; assert its label.)
-    await expect(page.locator('label[for="welcome-reduce-motion"]')).toBeVisible();
+    // The Speed control + Launch button sit right there, before the visitor launches.
+    await expect(page.locator("#welcome-play-speed")).toBeVisible();
     await expect(page.locator("#welcome-launch")).toBeVisible();
   });
 });
 
-test.describe("Task 5 — Reduced motion", () => {
-  test("reduce-motion toggle pauses video playback", async ({ page }) => {
-    await page.emulateMedia({ reducedMotion: "no-preference" }); // deterministic default-off
+test.describe("Task 5 — Playback speed slider (replaces Reduce motion)", () => {
+  test("the Reduce motion toggle is gone, replaced by a speed slider", async ({ page }) => {
+    await page.emulateMedia({ reducedMotion: "no-preference" });
     await page.goto("/");
-    await expect(page.locator("#welcome-reduce-motion")).not.toBeChecked(); // default-off under no-preference
-    await enter(page);                           // Video defaults on → experience runs
-    await page.waitForTimeout(500);
+    await enter(page);
+    await expect(page.locator("#reduce-motion")).toHaveCount(0);
+    const slider = page.locator("#play-speed");
+    await expect(slider).toBeVisible();
+    await expect(slider).toHaveValue("1");        // default = normal speed
+  });
+
+  test("forward speed sets the loop video's playbackRate", async ({ page }) => {
+    await page.emulateMedia({ reducedMotion: "no-preference" });
+    await page.goto("/");
+    await enter(page);
+    await page.locator("#play-speed").fill("2");
+    await expect
+      .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.playbackRate))
+      .toBe(2);
+  });
+
+  test("0x freezes the loop video", async ({ page }) => {
+    await page.emulateMedia({ reducedMotion: "no-preference" });
+    await page.goto("/");
+    await enter(page);
+    await page.locator("#play-speed").fill("0");
     await expect
       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
-      .toBe(false);                              // experience running → video plays
-    const rm = page.locator("#reduce-motion");
-    await page.locator('label[for="reduce-motion"]').click(); // hidden input: toggle via its label
-    await expect(rm).toBeChecked();
+      .toBe(true);
+  });
+
+  test("negative speed plays the loop in reverse (manual frame-stepping)", async ({ page }) => {
+    await page.emulateMedia({ reducedMotion: "no-preference" });
+    await page.goto("/");
+    await enter(page);
+    await page.locator("#play-speed").fill("-1.5");
+    await page.waitForTimeout(150);
+    const a = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+    const paused = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused);
+    await page.waitForTimeout(250);
+    const b = await page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.currentTime);
+    // The reverse loop pauses the element and drives currentTime by hand — so the
+    // element reads paused, yet currentTime keeps moving (≠ forward play, ≠ freeze).
+    // (It may wrap loopStart→tail, so we assert movement, not a strict decrease.)
+    expect(paused).toBe(true);
+    expect(b).not.toBe(a);
+  });
+
+  test("OS reduced-motion disables the slider and freezes the loop", async ({ page }) => {
+    await page.emulateMedia({ reducedMotion: "reduce" });
+    await page.goto("/");
+    await enter(page);
+    await expect(page.locator("#play-speed")).toBeDisabled();
     await expect
       .poll(() => page.locator("#vid-loop").evaluate((v: HTMLVideoElement) => v.paused))
-      .toBe(true);                               // reduced motion → frozen
+      .toBe(true); // OS prefers-reduced-motion → frozen regardless of slider
   });
 });
 
diff --git a/simulator/e2e/tests/altitude-lock.spec.ts b/simulator/e2e/tests/altitude-lock.spec.ts
index 1b316f5..32d9844 100644
--- a/simulator/e2e/tests/altitude-lock.spec.ts
+++ b/simulator/e2e/tests/altitude-lock.spec.ts
@@ -254,7 +254,8 @@ test("crossing a detent commits and locks the destination clip", async ({ page }
   const box = (await page.locator("#dial").boundingBox())!;
   const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
   // Drag clockwise across one full detent (top -> right ~= 90deg = 1.25 detents),
-  // crossing integer 1 (orbit) so it commits, then hold past it (no auto-complete).
+  // crossing integer 1 (orbit) so it commits, then hold past it WHILE STILL DRAGGING
+  // (the live blend holds wherever the knob is held; the snap happens only on release).
   await page.mouse.move(cx, cy - 30);
   await page.mouse.down();
   await page.mouse.move(cx + 30, cy + 6, { steps: 14 });
@@ -271,3 +272,30 @@ test("crossing a detent commits and locks the destination clip", async ({ page }
   expect(st2.activeClipId).toBe(st.activeClipId);
   await page.mouse.up();
 });
+
+test("releasing a partial drag snaps to the closest altitude (no held mid-blend)", async ({ page }) => {
+  // The operator can grab the dial, turn it PART of a detent, and let go between two
+  // altitudes. On release the knob must auto-scrub to the CLOSEST altitude and settle
+  // there (integer position, frac 0) — landing on a discrete altitude exactly as if
+  // they had clicked it, rather than holding the half-finished blend.
+  await boot(page);
+  const box = (await page.locator("#dial").boundingBox())!;
+  const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  await page.mouse.move(cx, cy - 30);
+  await page.mouse.down();
+  await page.mouse.move(cx + 18, cy - 24, { steps: 8 });   // ~0.5 detent — parks BETWEEN altitudes
+  // While held we are mid-blend: a fractional knob position.
+  await page.waitForFunction(
+    () => { const p = (window as any).__hefState().pos; return Math.abs(p - Math.round(p)) > 0.05; },
+    null, { timeout: 5000 },
+  );
+  await page.mouse.up();
+  // After release the position settles on an integer altitude (the snap).
+  await page.waitForFunction(
+    () => Number.isInteger((window as any).__hefState().pos),
+    null, { timeout: 10000 },
+  );
+  const st = await page.evaluate(() => (window as any).__hefState());
+  expect(Number.isInteger(st.pos)).toBe(true);   // landed on an altitude, not held mid-blend
+  expect(st.ringIndex).toBe(st.pos);             // committed altitude == the position it landed on
+});
diff --git a/simulator/e2e/tests/welcome.spec.ts b/simulator/e2e/tests/welcome.spec.ts
index d190932..172aa63 100644
--- a/simulator/e2e/tests/welcome.spec.ts
+++ b/simulator/e2e/tests/welcome.spec.ts
@@ -25,12 +25,12 @@ test("welcome screen shows on load with the expected defaults; the panel is hidd
   await expect(page.locator("#welcome")).toBeVisible();
   await expect(page.locator("#welcome")).toHaveClass(/welcoming/);
 
-  // Defaults: Video ON, Reduce motion OFF, Audio 2, English.
-  await expect(page.locator("#welcome-visual")).toBeChecked();
-  await expect(page.locator("#welcome-reduce-motion")).not.toBeChecked();
+  // Defaults: Language English, Speed 1, Audio 2.
+  await expect(page.locator("#welcome-lang")).toHaveValue("en");
+  await expect(page.locator("#welcome-play-speed")).toHaveValue("1");
+  await expect(page.locator("#welcome-play-speed-val")).toHaveText("1.00×");
   await expect(page.locator("#welcome-audio")).toHaveValue("2");
   await expect(page.locator("#welcome-audio-val")).toHaveText("2");
-  await expect(page.locator("#welcome-lang")).toHaveValue("en");
 
   // Heads-up + Launch button present; "Loading Universe" progress present.
   await expect(page.locator("#welcome-title")).toBeVisible();
@@ -66,7 +66,7 @@ test("Launch when already loaded enters the simulation directly and reveals the
   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
   await expect(page.locator(".panel")).toBeVisible();
 
-  // Welcome defaults carried into the panel: Video on, Audio 2.
+  // Welcome assumes Video on; Audio default 2 carried into the panel.
   await expect(page.locator("#visual")).toBeChecked();
   await expect(page.locator("#audio")).toHaveValue("2");
 });
@@ -76,14 +76,13 @@ test("welcome control values carry into the panel on entry", async ({ page }) =>
   await ready(page);
 
   await setRange(page, "welcome-audio", "5");
-  await page.locator('label[for="welcome-visual"]').click(); // default-on → off
-  await page.locator('label[for="welcome-reduce-motion"]').click(); // default-off → on
+  await setRange(page, "welcome-play-speed", "2"); // mirrors into the panel slider live
   await page.locator("#welcome-launch").click();
 
   await expect(page.locator("#welcome")).toHaveCount(0, { timeout: 5_000 });
   await expect(page.locator("#audio")).toHaveValue("5");
-  await expect(page.locator("#visual")).not.toBeChecked();
-  await expect(page.locator("#reduce-motion")).toBeChecked();
+  await expect(page.locator("#play-speed")).toHaveValue("2");
+  await expect(page.locator("#visual")).toBeChecked(); // welcome assumes video on
 });
 
 test("Launch while still loading shows the centered loader with controls, then auto-enters", async ({ page }) => {
diff --git a/simulator/static/app.js b/simulator/static/app.js
index 0f6b543..f353e5d 100644
--- a/simulator/static/app.js
+++ b/simulator/static/app.js
@@ -313,7 +313,7 @@ function loadLoop(clip, landFrame) {
 
 function playLoop() {
   if (isReduced()) return;     // reduced motion holds a still frame — never auto-play the loop
-  if (loopVid.paused) loopVid.play().catch(() => {});
+  applyPlaySpeed();            // honor the chosen speed/direction (forward, freeze, or reverse)
 }
 
 function ensureClipMedia() {
@@ -1076,7 +1076,11 @@ function onDialUp(e) {
     }
     return;
   }
-  // No auto-complete: hold the blend wherever the knob stopped (continuous-encoder model).
+  // Snap on release: a drag is a way of GRABBING the dial, not a free-standing
+  // encoder detent — so when the operator lets go between altitudes, auto-scrub the
+  // short way to the CLOSEST one and settle there (frac 0 locks). The result is the
+  // same as a tap/label-click: a grab-and-release always lands on a discrete altitude.
+  autoScrub(Math.round(pos));
 }
 
 // Click a label → auto-scrub the SHORTEST signed way around the ring to that scale.
@@ -1115,47 +1119,112 @@ function onDialKey(e) {
 // data the renderer already has (clips, ring, the alteration response, the preload
 // cache) — no server endpoints. Editing labels stays in /author.html.
 const DEV_KEY = "hef.devMode";
-const RM_KEY = "hef.reduceMotion";
+const SPEED_KEY = "hef.playSpeed";
 let devMode = false;
 let devStatsTimer = null;
 
-// --- Reduced motion (freeze-to-stills) ---------------------------------------
-// Default follows the OS `prefers-reduced-motion` until the visitor chooses, then
-// their choice persists. When ON: video holds a frame (paused), auto transitions
-// jump instantly instead of tweening — knob changes still re-grade the still.
-let reduceMotion = false;
-function isReduced() { return reduceMotion; }
-// Two checkboxes drive the same reduceMotion state: the welcome screen's and the
-// panel's. Either flips the flag, persists it, mirrors the other, and re-applies.
-const RM_BOXES = ["welcome-reduce-motion", "reduce-motion"];
-function syncReduceMotionBoxes() {
-  for (const id of RM_BOXES) { const b = $(id); if (b && b.checked !== reduceMotion) b.checked = reduceMotion; }
+// --- Playback speed + reduced motion -----------------------------------------
+// "Reduce motion" is no longer a visible toggle — its accessibility behavior is
+// derived LIVE from the OS `prefers-reduced-motion` setting (no persisted
+// override). The visible control is the Playback Speed slider, which drives ONLY
+// the resting altitude loop video (#vid-loop); the morph/transition video (#vid)
+// is scrub-driven and is never speed-controlled. Below 0x the loop plays in
+// reverse via a manual rAF loop (native negative playbackRate is unreliable —
+// Chrome ignores it). When the OS asks for reduced motion the loop stays frozen
+// and the slider is disabled, so a vestibular/photosensitive visitor never gets
+// motion they did not ask for.
+const SPEED_EPS = 0.02;               // |speed| below this = freeze (treat as 0)
+let playSpeed = 1;
+let revRaf = 0;                       // rAF handle for the manual reverse loop
+let revLast = 0;                      // last rAF timestamp (ms) for dt
+const reduceMq = (window.matchMedia && window.matchMedia("(prefers-reduced-motion: reduce)")) || null;
+function isReduced() { return !!(reduceMq && reduceMq.matches); }
+
+function stopReverse() {
+  if (revRaf) { cancelAnimationFrame(revRaf); revRaf = 0; }
 }
-function initReduceMotion() {
+// One reverse-loop frame: step #vid-loop's currentTime backward via the pure
+// HEFScrub.reverseStep math, then schedule the next. dt is capped so a stalled
+// tab can't make a giant jump.
+function reverseTick(now) {
+  if (!revRaf) return;
+  const dt = revLast ? Math.min((now - revLast) / 1000, 0.1) : 0;
+  revLast = now;
+  const dur = loopVid.duration;
+  if (Number.isFinite(dur) && dur > 0 && dt > 0) {
+    const r = HEFScrub.reverseStep(loopVid.currentTime, Math.abs(playSpeed), dt, loopStartFrame(), dur);
+    try { loopVid.currentTime = r.next; } catch (_) { /* not seekable yet */ }
+  }
+  revRaf = requestAnimationFrame(reverseTick);
+}
+function startReverse() {
+  if (revRaf) return;
+  loopVid.pause();                    // the rAF owns the element while reversing
+  revLast = 0;
+  revRaf = requestAnimationFrame(reverseTick);
+}
+// Apply the chosen slider speed to the resting loop video. When reduced motion
+// holds or video output is off, the freeze/play decision belongs to
+// syncReducedMotion / playLoop — here we only make sure no reverse loop is left
+// running and the forward rate is sane for when it resumes.
+function applyPlaySpeed() {
+  stopReverse();
+  if (isReduced() || !videoEverOn || !$("visual").checked) {
+    loopVid.playbackRate = Math.max(0.0625, Math.abs(playSpeed) || 1);
+    return;
+  }
+  if (playSpeed > SPEED_EPS) {
+    loopVid.playbackRate = playSpeed;
+    if (loopVid.paused) loopVid.play().catch(() => {});
+  } else if (playSpeed < -SPEED_EPS) {
+    startReverse();
+  } else {
+    loopVid.pause();                  // ~0x → freeze on the current frame
+  }
+}
+// Both the welcome screen's slider and the panel's drive the same playSpeed; each
+// mirrors the other and the shared "1.00×" readout.
+const SPEED_SLIDERS = ["welcome-play-speed", "play-speed"];
+const SPEED_VALS = ["welcome-play-speed-val", "play-speed-val"];
+function syncSpeedSliders() {
+  for (const id of SPEED_SLIDERS) { const s = $(id); if (s && s.value !== String(playSpeed)) s.value = String(playSpeed); }
+}
+function updateSpeedLabel() {
+  const txt = playSpeed.toFixed(2).replace("-", "−") + "×";
+  for (const id of SPEED_VALS) { const el = $(id); if (el) el.textContent = txt; }
+}
+function initPlaySpeed() {
   let stored = null;
-  try { stored = localStorage.getItem(RM_KEY); } catch (_) {}
-  const prefers = window.matchMedia && window.matchMedia("(prefers-reduced-motion: reduce)").matches;
-  reduceMotion = stored === null ? !!prefers : stored === "1";
-  syncReduceMotionBoxes();
-  for (const id of RM_BOXES) {
-    const box = $(id);
-    if (!box) continue;
-    box.addEventListener("change", () => {
-      reduceMotion = box.checked;
-      try { localStorage.setItem(RM_KEY, reduceMotion ? "1" : "0"); } catch (_) {}
-      syncReduceMotionBoxes();
-      applyReduceMotion();
+  try { stored = localStorage.getItem(SPEED_KEY); } catch (_) {}
+  playSpeed = stored === null ? 1 : (parseFloat(stored) || 0);
+  syncSpeedSliders();
+  for (const id of SPEED_SLIDERS) {
+    const slider = $(id);
+    if (!slider) continue;
+    slider.addEventListener("input", () => {
+      playSpeed = parseFloat(slider.value) || 0;
+      try { localStorage.setItem(SPEED_KEY, String(playSpeed)); } catch (_) {}
+      syncSpeedSliders();
+      updateSpeedLabel();
+      applyPlaySpeed();
     });
   }
-  applyReduceMotion();
+  updateSpeedLabel();
+  syncReducedMotion();                // initial enable/disable + freeze/play state
+  if (reduceMq && reduceMq.addEventListener) reduceMq.addEventListener("change", syncReducedMotion);
 }
-function applyReduceMotion() {
-  if (reduceMotion) {
+// Reconcile to the OS prefers-reduced-motion setting: when reduced, freeze both
+// videos and disable the speed slider; otherwise (re)apply the chosen speed.
+function syncReducedMotion() {
+  const reduced = isReduced();
+  for (const id of SPEED_SLIDERS) { const s = $(id); if (s) s.disabled = reduced; }
+  if (reduced) {
+    stopReverse();
     if (autoRaf) { cancelAnimationFrame(autoRaf); autoRaf = 0; }
     vid.pause();
     loopVid.pause();
   } else if (videoEverOn && $("visual").checked) {
-    playLoop();                         // resume the held loop on opt-out
+    applyPlaySpeed();                   // resume the held loop at the chosen speed
   }
 }
 
@@ -1478,22 +1547,24 @@ let videoEverOn = false;      // has Video ever been switched on this session?
 let universeReady = false;    // has phase-1 preload finished (safe to enter)?
 let launchPending = false;    // did the visitor press Launch while still loading?
 
-// Begin the experience: mark video-on and play the soundtrack at the chosen
-// level. Called from the Launch gesture so the audio play() unlocks on Safari
-// (which blocks play() outside a user gesture). Idempotent via videoEverOn.
+// Begin the experience: mark video-on, play the soundtrack at the chosen level,
+// and start the resting loop at the chosen speed. Called from the Launch gesture
+// so the audio play() unlocks on Safari (which blocks play() outside a user
+// gesture). Idempotent via videoEverOn.
 function beginExperience() {
   videoEverOn = true;
   updateAudioLevelLabel();
   applyAudio();
+  applyPlaySpeed();
 }
 
 // Welcome screen ----------------------------------------------------------------
-// The welcome controls are mirrors of the panel controls. Reduce-motion and
-// language drive shared state live (see initReduceMotion / setLanguage); Video and
-// Audio are copied into the panel inputs at entry.
+// The welcome controls mirror the panel controls. Speed and Language drive shared
+// state live (see initPlaySpeed / setLanguage). Video is assumed ON at entry; the
+// Audio level is copied into the panel input.
 function applyWelcomeToPanel() {
-  const wv = $("welcome-visual"), wa = $("welcome-audio");
-  if (wv) $("visual").checked = wv.checked;
+  $("visual").checked = true;   // the welcome screen assumes Video on (no toggle)
+  const wa = $("welcome-audio");
   if (wa) { $("audio").value = wa.value; updateAudioLevelLabel(); }
 }
 function updateWelcomeAudioLabel() {
@@ -1544,7 +1615,7 @@ async function main() {
   buildDial();                // draw the altitude knob from the ring's scales
   initDev();                  // wire the Dev Mode toggle + pool picker (reads persisted state)
   initLanguage();             // populate both language dropdowns + wire live switching
-  initReduceMotion();         // reduced-motion state + both toggles (default from OS pref)
+  initPlaySpeed();            // playback-speed sliders (welcome + panel) + OS-derived reduced motion
   initWelcome();              // wire the welcome-screen controls + Launch button
   renderScaleReadout();
   // Sliders stream on "input"; the toggles fire on "change".
diff --git a/simulator/static/i18n.js b/simulator/static/i18n.js
index 455e5ce..c131e86 100644
--- a/simulator/static/i18n.js
+++ b/simulator/static/i18n.js
@@ -31,9 +31,9 @@
     "knobs.feel":     { en: "Feel", es: "Sentir", fr: "Ressentir", ja: "感じる" },
     "knobs.mood":     { en: "Mood — dark ◀ 0 ▶ light", es: "Ánimo — oscuro ◀ 0 ▶ claro", fr: "Humeur — sombre ◀ 0 ▶ clair", ja: "ムード — 暗 ◀ 0 ▶ 明" },
     "devmode.label":  { en: "Dev Mode", es: "Modo desarrollo", fr: "Mode dév", ja: "開発モード" },
-    "rm.label":       { en: "Reduce motion", es: "Reducir movimiento", fr: "Réduire les animations", ja: "動きを減らす" },
+    "speed.label":    { en: "Speed", es: "Velocidad", fr: "Vitesse", ja: "再生速度" },
     "warn.title":     { en: "Heads up — motion & flashing", es: "Atención — movimiento y destellos", fr: "Attention — mouvement et flashs", ja: "ご注意 — 動きと点滅" },
-    "warn.body":      { en: "This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on “Reduce motion” below before you launch.", es: "Esta experiencia contiene movimiento continuo, destellos e imágenes cambiantes. Si eres sensible al movimiento o a las luces parpadeantes, activa «Reducir movimiento» abajo antes de iniciar.", fr: "Cette expérience contient des mouvements continus, des flashs et des images changeantes. Si vous êtes sensible au mouvement ou aux lumières clignotantes, activez « Réduire les animations » ci-dessous avant de lancer.", ja: "この体験には連続した動き、点滅、変化する映像が含まれます。動きや点滅する光に敏感な方は、起動する前に下の「動きを減らす」をオンにしてください。" },
+    "warn.body":      { en: "This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you launch — the experience honours it automatically.", es: "Esta experiencia contiene movimiento continuo, destellos e imágenes cambiantes. Si eres sensible al movimiento o a las luces parpadeantes, activa el ajuste «Reducir movimiento» de tu dispositivo antes de iniciar — la experiencia lo respeta automáticamente.", fr: "Cette expérience contient des mouvements continus, des flashs et des images changeantes. Si vous êtes sensible au mouvement ou aux lumières clignotantes, activez le réglage « Réduire les animations » de votre appareil avant de lancer — l’expérience le respecte automatiquement.", ja: "この体験には連続した動き、点滅、変化する映像が含まれます。動きや点滅する光に敏感な方は、起動する前にデバイスの「視差効果を減らす」設定をオンにしてください — 体験は自動的にそれに従います。" },
     "about.link":     { en: "About", es: "Acerca de", fr: "À propos", ja: "概要" },
     "scale.cosmos":   { en: "cosmos", es: "cosmos", fr: "cosmos", ja: "宇宙" },
     "scale.orbit":    { en: "orbit", es: "órbita", fr: "orbite", ja: "軌道" },
diff --git a/simulator/static/index.html b/simulator/static/index.html
index 7e44693..406d9a4 100644
--- a/simulator/static/index.html
+++ b/simulator/static/index.html
@@ -15,26 +15,21 @@
     <div class="welcome-inner">
       <div class="welcome-message">
         <h2 id="welcome-title" data-i18n="warn.title">Heads up — motion &amp; flashing</h2>
-        <p data-i18n="warn.body">This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on “Reduce motion” below before you launch.</p>
+        <p data-i18n="warn.body">This experience contains continuous motion, flashing, and shifting imagery. If you are sensitive to motion or flashing light, turn on your device’s “Reduce motion” setting before you launch — the experience honours it automatically.</p>
       </div>
       <div class="welcome-controls">
-        <label class="dev-switch" for="welcome-visual">
-          <input type="checkbox" id="welcome-visual" checked />
-          <span class="dev-switch-track"><span class="dev-switch-thumb"></span></span>
-          <span class="dev-switch-label" data-i18n="output.video">Video</span>
+        <label class="lang-pick">🌐
+          <select id="welcome-lang" aria-label="Language"></select>
+        </label>
+        <label class="audio-level play-speed"><span data-i18n="speed.label">Speed</span>
+          <input type="range" id="welcome-play-speed" min="-2" max="2" step="any" value="1"
+                 list="play-speed-ticks" aria-describedby="welcome-play-speed-val" />
+          <span id="welcome-play-speed-val">1.00×</span>
         </label>
         <label class="audio-level"><span data-i18n="output.audio">Audio</span>
           <input type="range" id="welcome-audio" min="0" max="10" value="2" step="1" />
           <span id="welcome-audio-val">2</span>/10
         </label>
-        <label class="dev-switch" for="welcome-reduce-motion">
-          <input type="checkbox" id="welcome-reduce-motion" />
-          <span class="dev-switch-track"><span class="dev-switch-thumb"></span></span>
-          <span class="dev-switch-label" data-i18n="rm.label">Reduce motion</span>
-        </label>
-        <label class="lang-pick">🌐
-          <select id="welcome-lang" aria-label="Language"></select>
-        </label>
       </div>
       <button type="button" id="welcome-launch" class="run-sim" data-i18n="welcome.launch">Launch Simulator</button>
       <div class="welcome-loading">
@@ -76,11 +71,19 @@
           <input type="range" id="audio" min="0" max="10" value="0" step="1" />
           <span id="audio-level-val">0</span>/10
         </label>
-        <label class="dev-switch" for="reduce-motion">
-          <input type="checkbox" id="reduce-motion" />
-          <span class="dev-switch-track"><span class="dev-switch-thumb"></span></span>
-          <span class="dev-switch-label" data-i18n="rm.label">Reduce motion</span>
+        <label class="audio-level play-speed"><span data-i18n="speed.label">Speed</span>
+          <input type="range" id="play-speed" min="-2" max="2" step="any" value="1"
+                 list="play-speed-ticks" aria-describedby="play-speed-val" />
+          <span id="play-speed-val">1.00×</span>
         </label>
+        <datalist id="play-speed-ticks">
+          <option value="-2"></option><option value="-1.75"></option><option value="-1.5"></option>
+          <option value="-1.25"></option><option value="-1"></option><option value="-0.75"></option>
+          <option value="-0.5"></option><option value="-0.25"></option><option value="0"></option>
+          <option value="0.25"></option><option value="0.5"></option><option value="0.75"></option>
+          <option value="1"></option><option value="1.25"></option><option value="1.5"></option>
+          <option value="1.75"></option><option value="2"></option>
+        </datalist>
         <label class="lang-pick">🌐
           <select id="lang-select" aria-label="Language"></select>
         </label>
diff --git a/simulator/static/scrub.js b/simulator/static/scrub.js
index 171de04..42f0cb6 100644
--- a/simulator/static/scrub.js
+++ b/simulator/static/scrub.js
@@ -41,6 +41,23 @@
     return dir < 0 ? 0 : loopTailS;
   }
 
+  // One frame of REVERSE loop playback for the resting altitude video. Native
+  // negative playbackRate is unreliable (Chrome ignores it), so app.js drives
+  // currentTime by hand; this is the pure math. The visible loop region is
+  // [loopStart, duration] (same frames the forward loop shows). Step back by
+  // absSpeed*dt; if it crosses below loopStart, wrap around to the tail
+  // (duration), carrying the overshoot modulo the region length so a big dt
+  // can't escape the region. Returns the next currentTime and whether a
+  // bottom-boundary wrap happened (so the caller can re-arm its loop state).
+  function reverseStep(t, absSpeed, dt, loopStart, duration) {
+    const L = duration - loopStart;
+    if (!(L > 0)) return { next: duration, wrapped: false };
+    const next = t - Math.abs(absSpeed) * dt;
+    if (next >= loopStart) return { next, wrapped: false };
+    const overshoot = (loopStart - next) % L;
+    return { next: duration - overshoot, wrapped: true };
+  }
+
   // Integers strictly crossed moving prevPos -> pos, in travel order. Landing
   // exactly on an integer counts as crossing it (it commits that altitude).
   function integerCrossings(prevPos, pos) {
@@ -53,5 +70,5 @@
     return out;
   }
 
-  return { clamp01, wrapIndex, segmentOf, accumToPos, fracToTime, crossfadeGains, loopLandFrame, integerCrossings };
+  return { clamp01, wrapIndex, segmentOf, accumToPos, fracToTime, crossfadeGains, loopLandFrame, reverseStep, integerCrossings };
 });
diff --git a/simulator/static/style.css b/simulator/static/style.css
index e8914c3..2bba2f2 100644
--- a/simulator/static/style.css
+++ b/simulator/static/style.css
@@ -153,6 +153,10 @@ input[type=range], select { width: 100%; }
                color: #9af; font-weight: 600; letter-spacing: 0.3px; }
 .audio-level input[type=range] { flex: 1; width: auto; }
 #audio-level-val { font-variant-numeric: tabular-nums; min-width: 1.2em; text-align: right; }
+/* Playback speed (−2×…2×) reuses the audio-level row look; wider value field for the sign + decimals. */
+#play-speed-val, #welcome-play-speed-val { font-variant-numeric: tabular-nums; min-width: 3.4em; text-align: right; }
+.play-speed input[type=range]:disabled { opacity: 0.4; cursor: not-allowed; }
+.play-speed:has(input:disabled) { opacity: 0.6; }
 .dev-panel { display: flex; flex-direction: column; gap: 0.8rem; }
 /* Beat the generic `.hidden` (defined earlier, equal specificity): two classes
    win, so the panel truly collapses when Dev Mode is off. */
diff --git a/simulator/unit/scrub.test.js b/simulator/unit/scrub.test.js
index 709c5f5..85e0ccd 100644
--- a/simulator/unit/scrub.test.js
+++ b/simulator/unit/scrub.test.js
@@ -59,6 +59,31 @@ test("integerCrossings: multiple crossings in travel order", () => {
   assert.deepEqual(S.integerCrossings(3.2, 1.8), [{ index: 3, dir: -1 }, { index: 2, dir: -1 }]);
 });
 
+test("reverseStep: decrements within the loop region without wrapping", () => {
+  // region [loopStart=3, duration=8]; step back absSpeed*dt = 0.5
+  assert.deepEqual(S.reverseStep(5, 1, 0.5, 3, 8), { next: 4.5, wrapped: false });
+  // landing exactly on the bottom boundary is the region edge, not a wrap
+  assert.deepEqual(S.reverseStep(3.5, 1, 0.5, 3, 8), { next: 3, wrapped: false });
+});
+
+test("reverseStep: wraps past the bottom boundary back to the tail (duration)", () => {
+  // 3.2 - 0.5 = 2.7 < 3 -> overshoot 0.3 -> 8 - 0.3 = 7.7
+  const r = S.reverseStep(3.2, 1, 0.5, 3, 8);
+  assert.equal(r.wrapped, true);
+  assert.ok(Math.abs(r.next - 7.7) < 1e-9, `next=${r.next}`);
+});
+
+test("reverseStep: overshoot larger than the region length wraps modulo", () => {
+  // region length L = 5; 3 - 7 = -4 -> overshoot 7 -> 7 % 5 = 2 -> 8 - 2 = 6
+  const r = S.reverseStep(3, 1, 7, 3, 8);
+  assert.equal(r.wrapped, true);
+  assert.ok(Math.abs(r.next - 6) < 1e-9, `next=${r.next}`);
+});
+
+test("reverseStep: degenerate region (duration <= loopStart) holds at duration", () => {
+  assert.deepEqual(S.reverseStep(3, 1, 0.5, 3, 3), { next: 3, wrapped: false });
+});
+
 test("loopLandFrame: descend lands on the morph's tail frame, ascend on its head", () => {
   // A morph spans src@0 (frac 0) -> dst@loopTailS (frac 1). Descending (dir>0) lands
   // on dst at frac 1 -> the base loop must continue from loopTailS. Ascending (dir<0)
diff --git a/tests/test_e2e_audio.py b/tests/test_e2e_audio.py
index 213153a..488ec73 100644
--- a/tests/test_e2e_audio.py
+++ b/tests/test_e2e_audio.py
@@ -120,9 +120,9 @@ def test_panel_silent_until_launch(page):
 
 def test_welcome_launch_shown_after_load_with_defaults(page):
     # Once media is preloaded the welcome screen shows its Launch button with the
-    # default controls (Video on, Audio 2) while the panel stays silent.
+    # default controls (Speed 1, Audio 2) while the panel stays silent.
     assert page.is_visible("#welcome-launch")
-    assert page.is_checked("#welcome-visual") is True
+    assert page.evaluate("document.getElementById('welcome-play-speed').value") == "1"
     assert page.evaluate("document.getElementById('welcome-audio').value") == "2"