HTML Opus #49
7.7
Evaluation
7.7 avg
8.5 physics accuracy
8.2 design quality
7.5 animation quality
5.5 slider ux
8.8 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 — the CSS rotates a horizontal range input with transform:rotate(-90deg) instead of using a native vertical input, and moving the thumb downward visually increases the value (crown submerges), but HTML range inputs when rotated this way actually map min at bottom and max at top, meaning top of the physical slider = fully submerged (100%) rather than in-air (0%), violating the spec; all other features are solid and physically grounded.

10,605 output tokens · claude-opus-4-6 · end_turn

Slider direction is inverted — the CSS rotates a horizontal range input with transform:rotate(-90deg) instead of using a native vertical input, and moving the thumb downward visually increases the value (crown submerges), but HTML range inputs when rotated this way actually map min at bottom and max at top, meaning top of the physical slider = fully submerged (100%) rather than in-air (0%), violating the spec; all other features are solid and physically grounded.