✓ 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 on most browsers (writing-mode vertical-lr + direction:rtl maps value=0 to bottom visually, not top), and crown position is driven continuously by slider value with no autonomous fall animation.
Slider direction is inverted on most browsers (writing-mode vertical-lr + direction:rtl maps value=0 to bottom visually, not top), and crown position is driven continuously by slider value with no autonomous fall animation.