✓ 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 means crowns in air is correct conceptually, but the vertical slider uses writing-mode + rotate(180deg) causing the physical top handle to map to max=100/water, making it unintuitive); no true fall animation (crown teleports based on slider value rather than animating a fall); ASCII art water shimmer uses Math.random() causing constant re-render flicker; physics values are plausible but the water-level calculation uses an arbitrary divisor (CONTAINER_WIDTH*10) rather than a properly scaled formula.
Slider direction is inverted (value=0 at top means crowns in air is correct conceptually, but the vertical slider uses writing-mode + rotate(180deg) causing the physical top handle to map to max=100/water, making it unintuitive); no true fall animation (crown teleports based on slider value rather than animating a fall); ASCII art water shimmer uses Math.random() causing constant re-render flicker; physics values are plausible but the water-level calculation uses an arbitrary divisor (CONTAINER_WIDTH*10) rather than a properly scaled formula.