✓ 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 crowns-in-air correctly in logic but the vertical slider's writing-mode/rtl rendering visually places high values at top, making the UX direction ambiguous/wrong); mass and density are static labels not live-updated spans, and there is no autonomous fall animation — crowns only move via manual slider drag.
Slider direction is inverted (min=0 at top maps to crowns-in-air correctly in logic but the vertical slider's writing-mode/rtl rendering visually places high values at top, making the UX direction ambiguous/wrong); mass and density are static labels not live-updated spans, and there is no autonomous fall animation — crowns only move via manual slider drag.