✓ 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 (value=0 starts crowns in air which is correct directionally, but the CSS rotation of the range input means the physical top of the slider corresponds to value=100/submerged, making the direction wrong for the user); water level drops rather than rises on submersion (y increases, height decreases — the math subtracts instead of adds); mass/volume/density values are static not live; fall animation is absent (crown teleports with no easing).
Slider is inverted (value=0 starts crowns in air which is correct directionally, but the CSS rotation of the range input means the physical top of the slider corresponds to value=100/submerged, making the direction wrong for the user); water level drops rather than rises on submersion (y increases, height decreases — the math subtracts instead of adds); mass/volume/density values are static not live; fall animation is absent (crown teleports with no easing).