✓ 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
Slider direction is inverted (top=air is correct conceptually but the submersion % label increases downward which maps to crown lowering into water — however, the water-rise math uses broken pixel-to-volume ratios producing implausible rise amounts, and splash particles append to the wrong parent element and fire continuously during drag rather than only on entry.
Slider direction is inverted (top=air is correct conceptually but the submersion % label increases downward which maps to crown lowering into water — however, the water-rise math uses broken pixel-to-volume ratios producing implausible rise amounts, and splash particles append to the wrong parent element and fire continuously during drag rather than only on entry.