✓ 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 controls water level but NOT crown position — crowns are drawn statically above the tank rather than descending into the water, so the core "falling crown" mechanic is absent and slider direction mapping is semantically inverted (value 0 = crowns fully above water, value 100 = water fills to top, but crowns never move).
Slider controls water level but NOT crown position — crowns are drawn statically above the tank rather than descending into the water, so the core "falling crown" mechanic is absent and slider direction mapping is semantically inverted (value 0 = crowns fully above water, value 100 = water fills to top, but crowns never move).