— 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
Implements a competent general Archimedes buoyancy demo with correct physics and a diagram tab, but is entirely off-brief: no two crowns (pure gold vs. gilded), no vertical immersion slider, no fall animation, no splash, no rising water level, no Heureka moment, and uses a dark background — nearly every Archimedes-crown-specific requirement is missing.
Implements a competent general Archimedes buoyancy demo with correct physics and a diagram tab, but is entirely off-brief: no two crowns (pure gold vs. gilded), no vertical immersion slider, no fall animation, no splash, no rising water level, no Heureka moment, and uses a dark background — nearly every Archimedes-crown-specific requirement is missing.