✓ 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 (LUFT at top label but slider max=100 maps to water, yet value=0 starts at top which is the HTML range default top-position, and the crown logic uses `100 - position` making top=air correctly — however the label says LUFT top / WASSER bottom while slider value increases downward, which is consistent, but no fall animation, no splash effects, and the ASCII crown rendering is glitchy (crown disappears/misplaces across rows due to fragile row arithmetic).
Slider direction is inverted (LUFT at top label but slider max=100 maps to water, yet value=0 starts at top which is the HTML range default top-position, and the crown logic uses `100 - position` making top=air correctly — however the label says LUFT top / WASSER bottom while slider value increases downward, which is consistent, but no fall animation, no splash effects, and the ASCII crown rendering is glitchy (crown disappears/misplaces across rows due to fragile row arithmetic).