:root {
  --pt-duration: 420ms;
  --pt-ease: cubic-bezier(0.16, 1, 0.3, 1);
  --pt-overlay: #161616;
  --pt-overlay-shadow: rgba(0, 0, 0, 0.25);
}

html {
  background: var(--pt-overlay);
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --pt-duration: 0ms;
  }
}

/* Overlay */
.page-transition-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  pointer-events: none;
  background: var(--pt-overlay);
  box-shadow: 0 0 0 1px var(--pt-overlay-shadow) inset;
  opacity: 0;
  clip-path: inset(100% 0 0 0);
  will-change: clip-path, opacity;
  transition: clip-path var(--pt-duration) var(--pt-ease),
    opacity var(--pt-duration) var(--pt-ease);
}

/* Entering: keep overlay covering on the next page, then JS removes the class to reveal */
html.pt-entering .page-transition-overlay {
  opacity: 1;
  pointer-events: auto;
  clip-path: inset(0 0 0 0);
}

/* Leaving: overlay covers from bottom -> top and page sinks/darkens */
body.pt-leaving .page-transition-overlay {
  opacity: 1;
  pointer-events: auto;
  clip-path: inset(0 0 0 0);
}

html.pt-entering .skip-link,
body.pt-leaving .skip-link {
  visibility: hidden !important;
  opacity: 0 !important;
  pointer-events: none !important;
  transform: translateY(calc(-100% - 1rem)) !important;
}

body.pt-leaving > :not(.page-transition-overlay):not(header):not(.square-button):not(.square-nav-panel):not(.skip-link) {
  transform-origin: 50% 40%;
  transform: translate3d(0, 40px, 0) scale(0.99);
  filter: brightness(0.7) saturate(0.9);
  opacity: 0.9;
  transition: transform var(--pt-duration) var(--pt-ease),
    filter var(--pt-duration) var(--pt-ease),
    opacity var(--pt-duration) var(--pt-ease);
  will-change: transform, filter, opacity;
}

/* Prevent accidental double clicks during transition */
body.pt-leaving a,
body.pt-leaving button {
  pointer-events: none !important;
}

/* If a legacy preload overlay exists, keep it aligned with the transition overlay color */
.preloader-screen {
  background-color: var(--pt-overlay);
}