✓ 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
Slider controls water level rather than crown positions (crowns drift via autonomous animation logic, not directly tied to slider), direction is inverted (value=0 means crowns in air, value=100 means water rising but that's framed as "water level" not crown descent), and the "fall animation" is a slow autonomous drift rather than a responsive slider-driven fall, breaking the core interaction mechanic.
Slider controls water level rather than crown positions (crowns drift via autonomous animation logic, not directly tied to slider), direction is inverted (value=0 means crowns in air, value=100 means water rising but that's framed as "water level" not crown descent), and the "fall animation" is a slow autonomous drift rather than a responsive slider-driven fall, breaking the core interaction mechanic.