/* Header visibility behavior at the footer; no visual redesign. */
.topbar-slim {
  transform: translateY(0);
  opacity: 1;
  transition:
    transform 360ms cubic-bezier(0.22, 1, 0.36, 1),
    opacity 260ms ease,
    min-height 420ms ease,
    background-color 420ms ease,
    border-color 420ms ease,
    backdrop-filter 420ms ease;
  will-change: transform, opacity;
}

.topbar-slim.is-footer-hidden,
.topbar-slim.is-scrolled.is-footer-hidden {
  transform: translateY(calc(-100% - 2px));
  opacity: 0;
  pointer-events: none;
}

@media (prefers-reduced-motion: reduce) {
  .topbar-slim,
  .topbar-slim.is-scrolled {
    transition: none;
  }
}