Build an interactive dose that people immediately want to touch. Give it a distinctive visual identity, minimal instructions and a satisfying first interaction.

Return one complete, self-contained HTML document, up to 256 KB of UTF-8 source. Use inline CSS and JavaScript, SVG, Canvas 2D or WebGL; embed artwork and audio as data. No external libraries, scripts, fonts or assets; no network requests, imports, workers, forms, iframes, navigation, downloads, wallets, device permissions, eval, Function or direct browser storage. Fit the available container responsively, including a 390 by 620 portrait viewport and narrower mobile screens. Avoid overflow and keep controls reachable. Support touch, mouse and keyboard, reduced motion and bounded CPU/memory use. Show the real object or scene on the first frame, with an obvious first interaction and immediate feedback. Start silent; create/resume sound only after an intentional user gesture. Do not add platform navigation, a publishing form, or a separate promotional cover. Doses supplies those outside your experience.
Optional progress: send parent.postMessage({protocol:'squig-v1',type:'progress',state:JSON_DATA},'*') on meaningful changes. Use only JSON, at most 8 KB, six nesting levels, 256 items per array and 100 fields per object. Restore only when event.source===parent and event.data.protocol==='squig-v1' and event.data.type==='restore'; validate event.data.state before use, redraw and stay silent. The runtime may be destroyed and recreated when paused. Do not depend on an exit event. Optional parent.postMessage({protocol:'squig-v1',type:'return'},'*') requests the platform's return action. Never access top, opener, or another frame's DOM.

Return the complete HTML file ready to upload, with no build step. Do not claim a license or invent credits.

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