✓ 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 (min=0 labeled "Luft" at top, max=100 labeled "Wasser" at bottom, but HTML range inputs render vertically with max at top when using writing-mode:vertical-lr + direction:rtl, making top=water and bottom=air in practice); physics values (gold 19.3, fake 8.5 g/cm³, same 1000g mass) are correct and displacement is proportional, but the "water rise" is displayed in pixels rather than physical units.
Slider direction is inverted (min=0 labeled "Luft" at top, max=100 labeled "Wasser" at bottom, but HTML range inputs render vertically with max at top when using writing-mode:vertical-lr + direction:rtl, making top=water and bottom=air in practice); physics values (gold 19.3, fake 8.5 g/cm³, same 1000g mass) are correct and displacement is proportional, but the "water rise" is displayed in pixels rather than physical units.