Windlass

Build a tiny browser game called "Windlass".

Game spec
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A well-head windlass puzzle. A bucket is chained down a stone well and you must raise it to the rim without spilling the water it carries and without snapping the chain. Hold Space or W (touch: hold the CRANK pad) to crank the drum and take up chain, release to stop; the crank has inertia, so it keeps turning a moment after you let go and can overrun. The bucket swings on the chain like a pendulum, and the swing is what spills: crank too fast and the bucket arcs against the shaft wall, losing water and damaging the chain, whose tension is shown on a live needle gauge. The well narrows near the top, so a wide swing up there is the dangerous part — ease off and let it settle. Hold Shift or the BRACE pad to brace the drum and kill the swing at the cost of time. Each bucket delivered pays by water remaining, chain condition and time; the next well is deeper, the bucket is smaller, and icy rims make the crank slip. Three buckets on easy, one on hard, with a bucket lost to a snapped chain or a dry delivery ending the run. Old stone well look: mossy coping, a wet chain with link highlights, a wooden crank with brass ferrule, a dark shaft with a water mirror that ripples as the bucket nears, and a chain-rattle sound in WebAudio.

Hard constraints — the game will be embedded in a sandboxed iframe on a static gallery site, and a headless browser will screenshot it:

1. Output exactly ONE self-contained HTML file. All CSS and JS inline. Zero external requests: no CDNs, no external fonts, images, or sounds, no fetch/XHR/WebSocket. Any sound must be synthesized with WebAudio.
2. The iframe sandbox is "allow-scripts allow-pointer-lock" (plus an autoplay permission). So: no localStorage, cookies, or indexedDB (opaque origin — access throws); no popups, window.open, or navigation; no access to the parent page; alert()/prompt()/confirm() are silently blocked.
3. The playfield must be visible within 800 ms of load — that is when the screenshot is taken. No dead white screen. If there is a start screen, make it visually rich.
4. Controls: keyboard AND mouse must both work, plus on-screen touch buttons for phones. Call preventDefault() on game keys (arrows, space) so the page never scrolls.
5. The view is 16:9 and must scale to fill the viewport with no overflow or scrollbars.
6. Show a visible score. If the genre has a losing state, show a game-over screen with a restart (button and a key). Idle/clicker games skip game over but still need clear numeric feedback.
7. If you track a score, report it to the arcade shell so the player's best is remembered between visits: on every score change, call parent.postMessage({ source: "ai-arcade", type: "score", score: <number> }, "*"). It is safe to call it no matter what the parent does with it.
8. Keep it tiny: aim for under 400 lines, 60 fps, no frameworks. That 400-line target does not apply to 3D games — true 3D (a camera and perspective-projected world) or pseudo-3D (projected road/track, depth-sorted sprites) — which need their own software renderer and typically land at 800–1400 lines. The rest of this constraint still binds every game: 60 fps, no frameworks, no external assets, and no padding to reach a length.
9. Difficulty: the arcade shell passes the player's chosen difficulty as a URL query parameter. Read it with new URLSearchParams(location.search).get("difficulty") — the value is "easy", "medium", or "hard" (missing or unknown means "medium"). Make the three levels meaningfully different — speed, lives, enemy pressure, reaction time, whatever fits the genre; clicker/idle games with no losing state use starting resources and upgrade cost curves instead. Show the active level in the HUD. Without the parameter the game must be fully playable at its default (medium) tuning.

Return only the complete HTML file, no commentary.