✓ 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 means crowns in air, but the HTML uses writing-mode/direction tricks on a standard range so dragging down increases value and submerges crowns — functionally inverted from the spec); all physics values are plausible and Heureka overlay with spinning rays is a standout feature.
Slider direction is inverted (value=0 at top means crowns in air, but the HTML uses writing-mode/direction tricks on a standard range so dragging down increases value and submerges crowns — functionally inverted from the spec); all physics values are plausible and Heureka overlay with spinning rays is a standout feature.