Dead Straight

Build "Dead Straight" — a polished mobile-first portrait web app for the Eazo community.

CONCEPT
A minimalist graphite-on-paper canvas. Draw one line in a single stroke: the app scores it live on straightness AND length — a short straight line is easy, a long straight line is legend. As you draw, your line glows greener the straighter it stays, flaring red where you wobble; a live protractor readout follows your fingertip.

RULES & STATES
- Score = straightness (0-100, from max perpendicular deviation) multiplied by a length bonus (up to x3 for edge-to-edge strokes).
- The stroke ends on finger lift; wobble zones are highlighted with small annotations ("the 8-pixel tremble").
- Three grades of flourish on reveal: confetti rule-lines for 90+, polite ruler stamp for 70+, a sympathetic wobbly doctor’s-signature joke below 50.
- Result card: your line drawn on a certificate with score, length, steadiest segment, and a rank title from Spaghetti Hands to Laser Level.

OPENING
No cover page: the app opens straight into the live interactive scene, playable on first paint. A floating title chip and one animated gesture hint dissolve on the first touch. Keep gentle ambient motion (drift, breathing, particles) at all times so the scene never looks frozen.

GLOBAL REQUIREMENTS
- Language: ship a lightweight built-in i18n layer with exactly two locales, English (en) and Chinese (zh). The app ALWAYS opens in English — never auto-detect or follow the system/browser language. Provide one small, comfortably tappable EN / 中文 toggle placed top-right, about 56px down from the top edge, clear of the device status bar. Chinese appears only after the user actively switches. All share output stays English regardless of locale. Never mix two languages on one screen.
- Fully self-contained: absolutely no external APIs of any kind — no AI calls, no third-party data, media or font services, no remote backend, no login. Embed all data and content in the app code.
- Real Share to the Eazo Community: on the result screen add a real Share button. Compose the result card as an image on a canvas and share it through the Eazo SDK community share (share.compose with the image attachment plus a short English text). Read the resolved { accepted } value: only when accepted is true may the button say "Sent to Eazo"; when accepted is false the button must read "Open in the Eazo app to share"; on error keep the original button. Never claim the post was shared on the plain web. Keep a Replay button next to Share.
- Mobile-first portrait, touch-only, no hover dependence. The app root must follow the host container height (position: fixed; inset: 0; height: 100%) — never 100dvh or 100svh. Size any canvas from its PARENT element using a ResizeObserver (run the fit once on mount), and convert every touch event through getBoundingClientRect() read at event time — never cache the rect and never use window.innerWidth/innerHeight for canvas sizing.
- Safe areas: keep all top UI at least 56px from the top edge. Keep every core interactive control (start button, submit, share, play controls) fully above the bottom 88px of the viewport — the Eazo mobile app overlays a native toolbar there that your code cannot detect.
- No background music and no autoplay audio.
- Complete real states: loading, empty, success, error where relevant. Every control must actually work — no alerts, console-log placeholders or fake results.
- Visual bar: rich, generous visual feedback on every touch (motion, particles, deformation, color, light) while keeping exactly ONE core rule understood within 3 seconds. Canvas 2D preferred for effects; do not use the canvas roundRect API (older iOS Safari lacks it). Never hardcode light text colors onto possibly-light backgrounds — derive text color from the theme.