✓ 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
Slider direction is inverted (min=0 at top maps to crowns in air, but vertical slider renders with 0 at bottom in most browsers, making "Water" label at bottom correspond to low values — direction logic is ambiguous/broken); physics values are plausible (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000g mass), but the data panel layout is broken (data-display div is inside .content flex row instead of below it, causing cramped layout), and the Heureka animation only appears on the left SVG.
Slider direction is inverted (min=0 at top maps to crowns in air, but vertical slider renders with 0 at bottom in most browsers, making "Water" label at bottom correspond to low values — direction logic is ambiguous/broken); physics values are plausible (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000g mass), but the data panel layout is broken (data-display div is inside .content flex row instead of below it, causing cramped layout), and the Heureka animation only appears on the left SVG.