✓ 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, well-structured implementation with correct Archimedes physics (same mass 1000 g, gold 51.8 cm³ vs. gilded 76.9 cm³), working vertical slider (0=air, 100=water), live data panels, splash particles, and Heureka animation — but crowns jump discretely to position rather than animating a smooth fall, and the buoyancy mN calculation is redundantly overwritten in the same block before being corrected.
Solid, well-structured implementation with correct Archimedes physics (same mass 1000 g, gold 51.8 cm³ vs. gilded 76.9 cm³), working vertical slider (0=air, 100=water), live data panels, splash particles, and Heureka animation — but crowns jump discretely to position rather than animating a smooth fall, and the buoyancy mN calculation is redundantly overwritten in the same block before being corrected.