✓ 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 top maps to air, max=100 at bottom maps to water, but the vertical slider CSS uses bt-lr writing-mode which physically renders bottom=low value/air, top=high value/water — user drags UP to submerge, opposite of the labeled ☁️ Luft top / 🌊 Wasser bottom intent), undermining the UX despite otherwise strong physics, visuals, and a full feature set.
10,889 output tokens · claude-opus-4-6 · end_turn
Slider direction is inverted (min=0 at top maps to air, max=100 at bottom maps to water, but the vertical slider CSS uses bt-lr writing-mode which physically renders bottom=low value/air, top=high value/water — user drags UP to submerge, opposite of the labeled ☁️ Luft top / 🌊 Wasser bottom intent), undermining the UX despite otherwise strong physics, visuals, and a full feature set.