✓ 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 but the writing-mode/rtl combination makes dragging upward increase submersion, counter to the prompt's "top=air, bottom=water" UX expectation); otherwise physics, visuals, and Heureka overlay are well-implemented.
Slider direction is inverted (value=0 at top means crowns in air is correct but the writing-mode/rtl combination makes dragging upward increase submersion, counter to the prompt's "top=air, bottom=water" UX expectation); otherwise physics, visuals, and Heureka overlay are well-implemented.