✓ 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
Solid ASCII-art implementation with correct physics (gold 19.3 g/cm³, alloy 13.0 g/cm³, same 1000 g mass), smooth interpolated slider, functional splash particles, and heureka reveal — but the ASCII rendering is cramped/overlapping and buoyancy units are displayed as mN when they should be N (off by 1000× with raw cm³ input).
Solid ASCII-art implementation with correct physics (gold 19.3 g/cm³, alloy 13.0 g/cm³, same 1000 g mass), smooth interpolated slider, functional splash particles, and heureka reveal — but the ASCII rendering is cramped/overlapping and buoyancy units are displayed as mN when they should be N (off by 1000× with raw cm³ input).