HTML Opus #19
7.8
Evaluation
7.8 avg
8.2 physics accuracy
8.5 design quality
7.8 animation quality
5.5 slider ux
9 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 is CSS-rotated (not a true vertical input) and its direction is inverted — dragging down increases value from 0→100, meaning slider-bottom=water is correct logically but the visual orientation with rotate(-90deg) makes top of the rendered thumb correspond to max/water, which is direction-correct by feel but ambiguous; the bigger flaw is the splash triggers at a fixed t=0.3 threshold regardless of actual crown-water contact, making timing imprecise.

10,198 output tokens · claude-opus-4-6 · end_turn

Slider is CSS-rotated (not a true vertical input) and its direction is inverted — dragging down increases value from 0→100, meaning slider-bottom=water is correct logically but the visual orientation with rotate(-90deg) makes top of the rendered thumb correspond to max/water, which is direction-correct by feel but ambiguous; the bigger flaw is the splash triggers at a fixed t=0.3 threshold regardless of actual crown-water contact, making timing imprecise.