✓ 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 at top = crowns in air is correct by default HTML range behavior, but the vertical slider via writing-mode renders top as max=100 visually, making full-down = crowns out of water); crown animation is ASCII-only with no smooth fall, and the crowns disappear rather than visually submerge when fully underwater.
Slider direction is inverted (value=0 at top = crowns in air is correct by default HTML range behavior, but the vertical slider via writing-mode renders top as max=100 visually, making full-down = crowns out of water); crown animation is ASCII-only with no smooth fall, and the crowns disappear rather than visually submerge when fully underwater.