✓ Two crowns ✓ Same mass, different density ✓ Vertical slider ✓ Slider works ✓ Slider controls crowns ✓ Slider direction correct ✓ Full slider range ✓ Fall animation ✓ Water displacement ✓ Rising water level ✓ Splash effects ✓ Physics correct ✓ Live mass value ✓ Live volume value ✓ Live density value ✓ Live displaced water ✓ Gilded displaces more ✓ Heureka animation ✓ No external deps ✓ Light bg / dark text ✓ Self-contained HTML
All required features are implemented with correct physics (gold 19.3 g/cm³, gilded 13.5 g/cm³, same 1000 g mass), but the slider UX relies on raw SVG drag-tracking with imprecise hit detection and no native range input, making interaction fiddly; the Heureka scale transform arithmetic is slightly off (divides x/y by scale instead of using a proper transform-origin).
11,926 output tokens · claude-opus-4-6 · end_turn
All required features are implemented with correct physics (gold 19.3 g/cm³, gilded 13.5 g/cm³, same 1000 g mass), but the slider UX relies on raw SVG drag-tracking with imprecise hit detection and no native range input, making interaction fiddly; the Heureka scale transform arithmetic is slightly off (divides x/y by scale instead of using a proper transform-origin).