✓ 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 places crowns in air but SVG-vertical behavior maps top=low value, bottom=high value incorrectly for a vertical range); mass, volume, and density are static labels rather than live-updating values; no smooth fall animation (crowns teleport proportionally with slider); Heureka animation uses a zero-duration initial state then re-triggers correctly.
Slider direction is inverted (value=0 places crowns in air but SVG-vertical behavior maps top=low value, bottom=high value incorrectly for a vertical range); mass, volume, and density are static labels rather than live-updating values; no smooth fall animation (crowns teleport proportionally with slider); Heureka animation uses a zero-duration initial state then re-triggers correctly.