✓ 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
Exceptionally complete implementation hitting every required feature with correct physics (ρ_gold=19300, ρ_fake=7800, same 1kg mass, ~2.5× volume ratio), SMIL-based splash particles, animated Heureka overlay, and live panel readouts; main weaknesses are that the volume display misleadingly shows "displaced so far / total" rather than a clean displaced value, and the water-rise delta-h numbers (using an assumed 400 cm² tank area) are not grounded in the SVG geometry actually shown.
Exceptionally complete implementation hitting every required feature with correct physics (ρ_gold=19300, ρ_fake=7800, same 1kg mass, ~2.5× volume ratio), SMIL-based splash particles, animated Heureka overlay, and live panel readouts; main weaknesses are that the volume display misleadingly shows "displaced so far / total" rather than a clean displaced value, and the water-rise delta-h numbers (using an assumed 400 cm² tank area) are not grounded in the SVG geometry actually shown.