✓ 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 (label says top=Luft/air but the slider's vertical-lr+rtl orientation and value=0 at top maps to crowns above water correctly in DOM — however the crown animation is absent as a smooth fall; no CSS/JS transition animates crown movement frame-by-frame, the crown simply jumps to the slider position without a timed fall sequence.
Slider direction is inverted (label says top=Luft/air but the slider's vertical-lr+rtl orientation and value=0 at top maps to crowns above water correctly in DOM — however the crown animation is absent as a smooth fall; no CSS/JS transition animates crown movement frame-by-frame, the crown simply jumps to the slider position without a timed fall sequence.