✓ 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
Physics values are directionally correct (same mass, gold ~19.3 vs gilded ~13.3 g/cm³, larger volume displaces more) but the water-level rise calculation is dimensionally inconsistent (mixes px-based submerged ratios with cm³ volumes divided by an arbitrary container width constant), making the water rise numbers physically meaningless; the custom drag-based vertical slider works but lacks a native range input and has no touch-prevention on scroll, and the gilded crown's density of 13.3 g/cm³ is plausible but unlabeled as a gold-silver alloy.
Physics values are directionally correct (same mass, gold ~19.3 vs gilded ~13.3 g/cm³, larger volume displaces more) but the water-level rise calculation is dimensionally inconsistent (mixes px-based submerged ratios with cm³ volumes divided by an arbitrary container width constant), making the water rise numbers physically meaningless; the custom drag-based vertical slider works but lacks a native range input and has no touch-prevention on scroll, and the gilded crown's density of 13.3 g/cm³ is plausible but unlabeled as a gold-silver alloy.