✓ 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 at top label "Luft"/air maps to crowns in air, but the writing-mode/direction CSS flips the visual so the physical top of the slider corresponds to slider value 0, which is correct logically — however the native vertical range with direction:rtl and writing-mode:vertical-lr means dragging up increases value, placing crowns in water, making top=water behaviorally, which is inverted); no autonomous fall animation (crowns only move via slider drag, no timed drop sequence); mass/density/volume values are static not recalculated live (they are hardcoded strings in the SVG, not truly dynamic).
Slider direction is inverted (min=0 at top label "Luft"/air maps to crowns in air, but the writing-mode/direction CSS flips the visual so the physical top of the slider corresponds to slider value 0, which is correct logically — however the native vertical range with direction:rtl and writing-mode:vertical-lr means dragging up increases value, placing crowns in water, making top=water behaviorally, which is inverted); no autonomous fall animation (crowns only move via slider drag, no timed drop sequence); mass/density/volume values are static not recalculated live (they are hardcoded strings in the SVG, not truly dynamic).