✓ 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
Physics values are correct (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000g mass) and water displacement updates live, but mass/volume/density are static labels rather than live values, there is no smooth fall animation (crowns teleport), and the water height calculation has a circular dependency bug (submersion fraction uses water1.offsetHeight which itself depends on displaced volume, creating an inconsistent feedback loop).
Physics values are correct (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000g mass) and water displacement updates live, but mass/volume/density are static labels rather than live values, there is no smooth fall animation (crowns teleport), and the water height calculation has a circular dependency bug (submersion fraction uses water1.offsetHeight which itself depends on displaced volume, creating an inconsistent feedback loop).