✓ 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 at top maps crowns to air correctly, but HTML range sliders render min at bottom, so dragging up moves crowns into water — opposite of stated intent); mass/volume/density values are static labels, not live-updating displays; no smooth fall animation, crowns teleport with slider position.
Slider direction is inverted (min=0 at top maps crowns to air correctly, but HTML range sliders render min at bottom, so dragging up moves crowns into water — opposite of stated intent); mass/volume/density values are static labels, not live-updating displays; no smooth fall animation, crowns teleport with slider position.