html.page-initializing body { visibility: hidden; }
/* Keep the persistent GPU layer inside a stable page stacking context. */
body { isolation: isolate; }
.fog-background {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
  opacity: 0;
}
.fog-background[data-ready="true"] { opacity: 1; }
.fog-background canvas { display: block; width: 100%; height: 100%; }
@media (prefers-reduced-motion: reduce) {
  .fog-background { display: none; }
}