/* CPO: lateral photographic shutters, opposed panels, short row arrivals.
   Fully visible base state; animation exists only after an observed entry. */
main { overflow-x: clip; }
[data-cpo-motion] { --cpo-travel: 64px; }
[data-cpo-motion="photo"] { --cpo-travel: 128px; }
[data-cpo-motion="row"] { --cpo-travel: 22px; }
.operations-v4 .chapter-frame { min-width: 0; overflow: hidden; aspect-ratio: 16/10; align-self: center; }
.operations-v4 .chapter-frame .chapter-photo {
  width: 100%; height: 100%; aspect-ratio: auto;
  transform: translateX(var(--cpo-depth-x, 0px)) scale(1.075);
  transition: none;
}
@media(min-width:900px) { #services-maintenance .chapter-frame { order: 2; } }
.field-chapters button { position: relative; }
.field-chapters button::after {
  content: ''; position: absolute; left: 0; right: 0; bottom: 0;
  height: 2px; background: currentColor; transform: scaleX(0);
  transform-origin: left; transition: transform 250ms ease;
}
.field-chapters button[aria-pressed="true"]::after { transform: scaleX(1); }
@media(max-width:899px) {
  .operations-v4 .chapter-frame { aspect-ratio: 16/9; }
  [data-cpo-motion] { --cpo-travel: 25px; }
  [data-cpo-motion="photo"] { --cpo-travel: 36px; }
}
@media(max-width:600px) {
  [data-cpo-motion], [data-cpo-motion="row"] { --cpo-travel: 14px; }
  [data-cpo-motion="photo"] { --cpo-travel: 20px; }
}
@media(prefers-reduced-motion:reduce) {
  .operations-v4 .chapter-frame .chapter-photo { transform: none; }
  .field-chapters button::after { transition: none; }
}