✓ 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 (label says "IN WASSER" at top but value=0 at top means crowns start out of water — confusingly labelled), crown fall animation is absent (crowns jump via CSS top positioning, no smooth transition), splash physics are broken (vx/vy are const-shadowed by let in the interval closure so wind/gravity don't accumulate), water-level rise formula is arbitrary and tiny, and eureka triggers only in the narrow band 95–105 which works for 95–100 but the logic is sound; static mass/volume/density values never update dynamically.
Slider direction is inverted (label says "IN WASSER" at top but value=0 at top means crowns start out of water — confusingly labelled), crown fall animation is absent (crowns jump via CSS top positioning, no smooth transition), splash physics are broken (vx/vy are const-shadowed by let in the interval closure so wind/gravity don't accumulate), water-level rise formula is arbitrary and tiny, and eureka triggers only in the narrow band 95–105 which works for 95–100 but the logic is sound; static mass/volume/density values never update dynamically.