✓ 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 technically correct internally, but the visual thumb logic and the "Ins Wasser eintauchen ▼" label with water at bottom of track means increasing slider value = crowns descend into water — however the slider's writing-mode/direction CSS means the native slider thumb moves opposite to expectation, making UX confusing); buoyancy force calculation uses raw cm³ without the 1e-6 m³ conversion yielding near-zero Newton values (~5e-4 N instead of ~0.5 N), a physics display error.
Slider direction is inverted (value=0 at top maps to crowns in air, which is technically correct internally, but the visual thumb logic and the "Ins Wasser eintauchen ▼" label with water at bottom of track means increasing slider value = crowns descend into water — however the slider's writing-mode/direction CSS means the native slider thumb moves opposite to expectation, making UX confusing); buoyancy force calculation uses raw cm³ without the 1e-6 m³ conversion yielding near-zero Newton values (~5e-4 N instead of ~0.5 N), a physics display error.