✓ 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 solid physics (gold 19.32 g/cm³, gilded 12.50 g/cm³, same 1000 g mass), smooth canvas animations including splash particles, ripples, bubbles, and a rising water level indicator, but the slider direction uses a non-standard vertical CSS writing-mode approach that may behave inconsistently across browsers, and the water-rise pixel scaling is visually arbitrary rather than geometrically derived from tank dimensions.
12,017 output tokens · claude-opus-4-6 · end_turn
All required features are implemented with solid physics (gold 19.32 g/cm³, gilded 12.50 g/cm³, same 1000 g mass), smooth canvas animations including splash particles, ripples, bubbles, and a rising water level indicator, but the slider direction uses a non-standard vertical CSS writing-mode approach that may behave inconsistently across browsers, and the water-rise pixel scaling is visually arbitrary rather than geometrically derived from tank dimensions.