✓ 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 is horizontal (not vertical) and direction is inverted (0=air at left, 100=water at right rather than top=air/bottom=water); ASCII-art canvas is functional but crude, and both crowns move identically with no visual differentiation of displacement between them.
Slider is horizontal (not vertical) and direction is inverted (0=air at left, 100=water at right rather than top=air/bottom=water); ASCII-art canvas is functional but crude, and both crowns move identically with no visual differentiation of displacement between them.