✓ 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 (0=air at top label, 100=water at bottom label maps correctly in UI text, but the vertical range input's visual top corresponds to value=100/water, making the physical drag direction backwards); no smooth fall animation — crown teleports based on slider ratio; splash is random noise pixels rather than a real particle effect.
Slider direction is inverted (0=air at top label, 100=water at bottom label maps correctly in UI text, but the vertical range input's visual top corresponds to value=100/water, making the physical drag direction backwards); no smooth fall animation — crown teleports based on slider ratio; splash is random noise pixels rather than a real particle effect.