✓ 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
Solid implementation with correct physics (gold 19.3 g/cm³ vs alloy 13.0 g/cm³, same 1000g mass, proportionally larger displacement for gilded crown), but lacks a true fall animation — crowns teleport linearly with the slider rather than animating autonomously, and density/mass/volume values are static text rather than dynamically computed live values.
Solid implementation with correct physics (gold 19.3 g/cm³ vs alloy 13.0 g/cm³, same 1000g mass, proportionally larger displacement for gilded crown), but lacks a true fall animation — crowns teleport linearly with the slider rather than animating autonomously, and density/mass/volume values are static text rather than dynamically computed live values.