✓ 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 (value=0 at top = crowns in air, but slider thumb starts at top and increasing value should move crowns down — however the crown Y position formula `22 - depth*0.15` moves the crown UP as depth increases, which is backwards); particle splash exists but is computed in ASCII-space and rarely visible; no actual fall animation, just instant repositioning; Heureka triggers correctly at depth=100.
Slider direction is inverted (value=0 at top = crowns in air, but slider thumb starts at top and increasing value should move crowns down — however the crown Y position formula `22 - depth*0.15` moves the crown UP as depth increases, which is backwards); particle splash exists but is computed in ASCII-space and rarely visible; no actual fall animation, just instant repositioning; Heureka triggers correctly at depth=100.