✓ 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
All required features are implemented with correct physics (ρ_gold=19.32, ρ_fake=11.0, same 1000g mass), live data panel, comparison bar chart, splash/ripple/bubble effects, and Heureka overlay; main weakness is the CSS-rotated horizontal slider which is less ergonomic than a native vertical input, and the submerged-fraction calculation uses the raw slider value for data display rather than the geometrically computed value.
12,444 output tokens · claude-opus-4-6 · end_turn
All required features are implemented with correct physics (ρ_gold=19.32, ρ_fake=11.0, same 1000g mass), live data panel, comparison bar chart, splash/ripple/bubble effects, and Heureka overlay; main weakness is the CSS-rotated horizontal slider which is less ergonomic than a native vertical input, and the submerged-fraction calculation uses the raw slider value for data display rather than the geometrically computed value.