✓ 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, visually polished implementation with correct physics (ρ_gold=19.3, ρ_fake=9.0, same mass=1000g) and a nice Heureka overlay, but crown positions are recalculated by rebuilding DOM nodes on every slider tick rather than using transforms, and the fall animation is stepwise/immediate rather than a smooth timed drop since it's purely slider-driven with no autonomous fall sequence.
Comprehensive, visually polished implementation with correct physics (ρ_gold=19.3, ρ_fake=9.0, same mass=1000g) and a nice Heureka overlay, but crown positions are recalculated by rebuilding DOM nodes on every slider tick rather than using transforms, and the fall animation is stepwise/immediate rather than a smooth timed drop since it's purely slider-driven with no autonomous fall sequence.