✓ 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 is inverted (min=0/top=air maps correctly by HTML default but `appearance: slider-vertical` on a range with value=0 at top actually renders bottom=0 in most browsers, so top=fully-submerged, bottom=in-air); no fall animation (crowns jump instantly); displaced volume is a fraction of total crown volume but the submergedDepth/60 ratio is arbitrary and not tied to real geometry; water level rise formula uses a nonsensical area calculation.
Slider is inverted (min=0/top=air maps correctly by HTML default but `appearance: slider-vertical` on a range with value=0 at top actually renders bottom=0 in most browsers, so top=fully-submerged, bottom=in-air); no fall animation (crowns jump instantly); displaced volume is a fraction of total crown volume but the submergedDepth/60 ratio is arbitrary and not tied to real geometry; water level rise formula uses a nonsensical area calculation.