Gray expanding circle was caused by UA default animations (fade-in/out)
and mix-blend-mode: plus-lighter not being fully overridden by WAAPI
opacity animations alone.
Fix: use CSS with !important to hard-lock the VT pseudo-elements:
- animation: none !important — kills UA fade-in/out
- opacity: 1 !important — both layers stay fully opaque
- mix-blend-mode: normal !important — no color addition
WAAPI now only controls clip-path on ::view-transition-new(root),
which doesn't conflict with any CSS property (no CSS clip-path exists).
This cleanly separates concerns: CSS handles static properties,
WAAPI handles the dynamic circle expansion.