/* Short control feedback, with no scroll listeners or persistent GPU layers. */
@media (prefers-reduced-motion: no-preference) {
  /* Prepare only offscreen headings, so entering never dims visible text first. */
  .section-heading.motion-pending,.section-intro.motion-pending { opacity:.72; transform:translateY(8px); }
  .results-modes button,.quiet-button,.archive-lab-toggle,.archive-model,.usage-table thead button {
    transition: color 160ms ease, border-color 160ms ease, background-color 160ms ease;
  }
  .paper details > summary { transition:color 160ms ease; }
  .paper details > summary:is(:hover,:focus-visible) { color:var(--blue); }
  .results-modes button:active,.quiet-button:active { transform:translateY(1px); }
  .archive-lab-menu:popover-open { animation: model-menu-enter 160ms cubic-bezier(.22,1,.36,1); }
}
@keyframes model-menu-enter {
  from { opacity:0;transform:translateY(-4px); }
  to { opacity:1;transform:translateY(0); }
}