✓ 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 present and physically coherent (gold ρ=19.3, gilded ρ=13.0, same mass, correct buoyancy formula), but the slider is a rotated horizontal input rather than a native vertical one, and the immersion-logic bug (cTop >= waterY → immersion=1 check fires before the water-rises iteration converges) can cause the crowns to jump to fully submerged slightly too early.
9,564 output tokens · claude-opus-4-6 · end_turn
All required features are present and physically coherent (gold ρ=19.3, gilded ρ=13.0, same mass, correct buoyancy formula), but the slider is a rotated horizontal input rather than a native vertical one, and the immersion-logic bug (cTop >= waterY → immersion=1 check fires before the water-rises iteration converges) can cause the crowns to jump to fully submerged slightly too early.