✓ 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
Physics values are correct (1000 g, 19.3 vs 13.0 g/cm³) and displacement scales properly, but crown animation is absent — the crown Y moves upward (not downward into water) as slider increases, the crown visually rises rather than falls/sinks, making the motion counterintuitive; splash effects are static random dots re-drawn each frame rather than true animated particles.
Physics values are correct (1000 g, 19.3 vs 13.0 g/cm³) and displacement scales properly, but crown animation is absent — the crown Y moves upward (not downward into water) as slider increases, the crown visually rises rather than falls/sinks, making the motion counterintuitive; splash effects are static random dots re-drawn each frame rather than true animated particles.