✓ 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, complete implementation with correct physics (same mass 1000g, gold 19.3 g/cm³ vs alloy 13.0 g/cm³, rightful volume/displacement ratio), shimmer loop, splash/ripple on water entry, and Heureka animation at slider end — but lacks a true fall animation (crowns teleport to position rather than animating independently) and mass/volume values are static in infoL1/infoR1 rather than being live-computed text elements.
Solid, complete implementation with correct physics (same mass 1000g, gold 19.3 g/cm³ vs alloy 13.0 g/cm³, rightful volume/displacement ratio), shimmer loop, splash/ripple on water entry, and Heureka animation at slider end — but lacks a true fall animation (crowns teleport to position rather than animating independently) and mass/volume values are static in infoL1/infoR1 rather than being live-computed text elements.