✓ 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 which is correct, BUT the slider's default HTML orientation means dragging down increases value → crowns go down, which is physically correct but the visual slider top≠air labeling is ambiguous; more critically, crown motion is continuous but there is no discrete fall/drop animation — crowns simply translate smoothly without a timed drop sequence, and the Eureka trigger only fires on a single transition threshold making it unreliable on repeated use.
Slider direction is inverted (value=0 at top maps to crowns in air which is correct, BUT the slider's default HTML orientation means dragging down increases value → crowns go down, which is physically correct but the visual slider top≠air labeling is ambiguous; more critically, crown motion is continuous but there is no discrete fall/drop animation — crowns simply translate smoothly without a timed drop sequence, and the Eureka trigger only fires on a single transition threshold making it unreliable on repeated use.