✓ 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
Comprehensive implementation with correct physics (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000g mass, volumes 51.8 vs 76.9 cm³), clearly visible differential water rise, live readouts, splash effects, and Heureka animation, but crowns jump/teleport with the slider rather than animating a fall, and the splash animation has a minor determinism issue (random mid-animation call) that limits particle realism.
Comprehensive implementation with correct physics (gold 19.3 g/cm³, gilded 13.0 g/cm³, same 1000g mass, volumes 51.8 vs 76.9 cm³), clearly visible differential water rise, live readouts, splash effects, and Heureka animation, but crowns jump/teleport with the slider rather than animating a fall, and the splash animation has a minor determinism issue (random mid-animation call) that limits particle realism.