✓ 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 is top/air but crowns start submerged; semantically 0→air is correct in mapping but labeled "Oben=0/Unten=100" which is fine, however the slider HTML input with writing-mode bt-lr means visually dragging down increases value which is correct), no fall or splash animations, crown rendering is a single character with no real submersion visual, and ASCII art water is randomly re-generated on every redraw causing visual noise rather than smooth animation.
Slider direction is inverted (value=0 is top/air but crowns start submerged; semantically 0→air is correct in mapping but labeled "Oben=0/Unten=100" which is fine, however the slider HTML input with writing-mode bt-lr means visually dragging down increases value which is correct), no fall or splash animations, crown rendering is a single character with no real submersion visual, and ASCII art water is randomly re-generated on every redraw causing visual noise rather than smooth animation.