✓ 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 (1000 g, ρ_gold=19.32, ρ_fake=13.10), but the water-rise scale factor (0.5 px/cm³) is arbitrary and visually understates the displacement difference; mass/density panels are static (not truly "live" beyond displaced-water), and the SVG-native slider requires a drag-only interaction that lacks a clickable track highlight for UX polish.
11,258 output tokens · claude-opus-4-6 · end_turn
All required features are implemented with correct physics (1000 g, ρ_gold=19.32, ρ_fake=13.10), but the water-rise scale factor (0.5 px/cm³) is arbitrary and visually understates the displacement difference; mass/density panels are static (not truly "live" beyond displaced-water), and the SVG-native slider requires a drag-only interaction that lacks a clickable track highlight for UX polish.