✓ 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 maps to crowns in air via label "Oben", but the slider's vertical-lr/rtl CSS with min=0 at top actually sends crowns DOWN as you drag down — however the label says "Oben" at top and "Unten" at bottom which is correct in labeling, but the fall animation is absent (crowns jump instantly; no timed fall sequence), and mass/density/volume panels are static (not dynamically updated per slider position — only displaced water, buoyancy, and immersion update live).
Slider direction is inverted (value=0 at top maps to crowns in air via label "Oben", but the slider's vertical-lr/rtl CSS with min=0 at top actually sends crowns DOWN as you drag down — however the label says "Oben" at top and "Unten" at bottom which is correct in labeling, but the fall animation is absent (crowns jump instantly; no timed fall sequence), and mass/density/volume panels are static (not dynamically updated per slider position — only displaced water, buoyancy, and immersion update live).