✓ 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 feature completeness with correct physics (gold 19.3 g/cm³, gilded 8.0 g/cm³, same 1000g mass), Eureka modal, and rising water level, but the slider direction is inverted (writing-mode bt-lr + rotate(180deg) means dragging down increases depth, i.e. top=water/bottom=air), and the ASCII-art rendering is rudimentary with crowns represented as single characters making the "fall animation" and submersion visuals minimal.
Solid feature completeness with correct physics (gold 19.3 g/cm³, gilded 8.0 g/cm³, same 1000g mass), Eureka modal, and rising water level, but the slider direction is inverted (writing-mode bt-lr + rotate(180deg) means dragging down increases depth, i.e. top=water/bottom=air), and the ASCII-art rendering is rudimentary with crowns represented as single characters making the "fall animation" and submersion visuals minimal.