✓ 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 per label ("hochziehen um Kronen ins Wasser zu lassen" — drag up = submerge, but HTML range sliders default bottom=min/top=max making the mapping confusing), and crowns move linearly without a proper gravity/fall animation; water displacement math uses a rough pixel-to-volume proxy that undermines physics fidelity.
Slider direction is inverted per label ("hochziehen um Kronen ins Wasser zu lassen" — drag up = submerge, but HTML range sliders default bottom=min/top=max making the mapping confusing), and crowns move linearly without a proper gravity/fall animation; water displacement math uses a rough pixel-to-volume proxy that undermines physics fidelity.