✓ 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
Comprehensively implements all required features with correct Archimedes physics (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000 g mass), live data panels, splash particles, and Heureka overlay — minor weakness is that mass and density fields are static strings rather than dynamically computed, and the water-rise pixel scale is arbitrarily chosen rather than derived from a consistent unit system.
Comprehensively implements all required features with correct Archimedes physics (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000 g mass), live data panels, splash particles, and Heureka overlay — minor weakness is that mass and density fields are static strings rather than dynamically computed, and the water-rise pixel scale is arbitrarily chosen rather than derived from a consistent unit system.