✓ 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 (value=0/top maps to crowns in air, but the range input's visual top in vertical mode renders 0 at bottom, so dragging up submerges crowns rather than the expected top=air/bottom=water UX); ASCII-art scene is functional but fall animation is absent — crowns teleport rather than animate independently of slider movement.
Slider direction is inverted (value=0/top maps to crowns in air, but the range input's visual top in vertical mode renders 0 at bottom, so dragging up submerges crowns rather than the expected top=air/bottom=water UX); ASCII-art scene is functional but fall animation is absent — crowns teleport rather than animate independently of slider movement.