✓ 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 (min=0 labeled "Luft" at top, max=100 labeled "Wasser" at bottom is correct labeling, but the vertical slider's native rendering with writing-mode/direction places value=0 at the bottom in most browsers, meaning top of slider = water, bottom = air — direction logic is unreliable cross-browser); all other physics, animation, and feature coverage is impressively thorough.
Slider direction is inverted (min=0 labeled "Luft" at top, max=100 labeled "Wasser" at bottom is correct labeling, but the vertical slider's native rendering with writing-mode/direction places value=0 at the bottom in most browsers, meaning top of slider = water, bottom = air — direction logic is unreliable cross-browser); all other physics, animation, and feature coverage is impressively thorough.