✓ 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 — dragging down (max value) submerges crowns, but the labels say "▲ Luft" at top and "▼ Wasser" at bottom with slider min=0 at top, which in a vertical range with writing-mode+direction:rtl actually maps slider=0 to the bottom visually, making the physical mapping ambiguous/incorrect for native browser rendering of vertical sliders.
Slider direction is inverted — dragging down (max value) submerges crowns, but the labels say "▲ Luft" at top and "▼ Wasser" at bottom with slider min=0 at top, which in a vertical range with writing-mode+direction:rtl actually maps slider=0 to the bottom visually, making the physical mapping ambiguous/incorrect for native browser rendering of vertical sliders.