✓ 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 hitting every feature with correct physics (Au 19.32 g/cm³, alloy 13.15 g/cm³, same 1000 g mass, correct displaced-volume ratio), polished SVG visuals, bubbles, splash, and Eureka animation; main weakness is that the custom SVG slider lacks a native range element and the submersion fraction uses the crown's initial water Y rather than the rising surface, slightly underestimating submersion depth.
12,497 output tokens · claude-opus-4-6 · end_turn
Comprehensive implementation hitting every feature with correct physics (Au 19.32 g/cm³, alloy 13.15 g/cm³, same 1000 g mass, correct displaced-volume ratio), polished SVG visuals, bubbles, splash, and Eureka animation; main weakness is that the custom SVG slider lacks a native range element and the submersion fraction uses the crown's initial water Y rather than the rising surface, slightly underestimating submersion depth.