HTML Opus #15
7.8
Evaluation
7.8 avg
8.5 physics accuracy
8.5 design quality
8 animation quality
5.5 slider ux
8.5 completeness
7.8 overall
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 (min=0 at left/top maps to crowns above water, which is correct semantically, but the CSS `rotate(-90deg)` horizontal-to-vertical transform means dragging "up" visually increases the value — this creates an unintuitive feel); all physics (Archimedes, displaced volume, buoyancy force) are correctly implemented with plausible values, and the Heureka overlay, splash particles, rising water, and live data panel are all well-executed.

11,328 output tokens · claude-opus-4-6 · end_turn

Slider direction is inverted (min=0 at left/top maps to crowns above water, which is correct semantically, but the CSS `rotate(-90deg)` horizontal-to-vertical transform means dragging "up" visually increases the value — this creates an unintuitive feel); all physics (Archimedes, displaced volume, buoyancy force) are correctly implemented with plausible values, and the Heureka overlay, splash particles, rising water, and live data panel are all well-executed.