/* Native scrolling underneath a measured, bounded desktop chapter. */
.season-scroll { position:relative; }
.season-scroll.motion-season-active { height:var(--season-height); margin:92px auto; }
.season-scroll.motion-season-active > .chapter { position:sticky; top:24px; margin-block:0; padding-top:24px; padding-bottom:36px; }
.motion-season-active .episode-rail { scroll-snap-type:none; scroll-behavior:auto; }
.motion-season-active .chapter-heading p { transform:translateY(var(--season-text-y, 0px)); }
.motion-season-active .cover-link img,.motion-season-active .episode-card .cover-link:hover img { transform:scale(1.09) translateX(var(--season-image-x, 0px)); transition:none; }

/* The cover moves; the film's title, duration and purchase link remain stable. */
.episode-rail--coverflow { perspective:1100px; padding-top:18px; padding-bottom:30px; }
.episode-rail--coverflow .episode-card { perspective:1100px; }
.episode-rail--coverflow .cover-link { transform:rotateY(var(--cover-turn, 0deg)) rotateX(var(--hover-x, 0deg)) rotateY(var(--hover-y, 0deg)) scale(var(--cover-scale, 1)); transform-origin:center; transition:transform .22s cubic-bezier(.16, 1, .3, 1); backface-visibility:hidden; }
.episode-rail--coverflow .cover-link img,.episode-rail--coverflow .episode-card .cover-link:hover img { transform:none; }

/* Measured chapter progress extends the existing chapter navigation dots. */
.chapter-nav a { position:relative; }
.chapter-nav a::after { content:""; position:absolute; pointer-events:none; top:31px; left:21px; width:1px; height:17px; transform-origin:top; background:var(--blue); transform:scaleY(var(--chapter-progress, 0)); }
.chapter-nav a:last-child::after { display:none; }

@media (hover:none), (pointer:coarse) {
  .episode-rail--coverflow .cover-link { transition:none; }
}
@media (prefers-reduced-motion:reduce) {
  .season-scroll.motion-season-active { height:auto; margin:0; }
  .season-scroll.motion-season-active > .chapter { position:relative; top:auto; margin:92px auto; padding-block:0; }
  .motion-season-active .episode-rail { scroll-snap-type:x mandatory; }
  .motion-season-active .chapter-heading p,.motion-season-active .cover-link img,.episode-rail--coverflow .cover-link { transform:none; transition:none; }
}