/* Scroll-sequence layout. The section is TALL (--seq-scroll) to give
   scrub distance; the canvas is PINNED (sticky) so the product holds
   still on screen while you scroll through its frames. */

.seq {
  position: relative;
  height: var(--seq-scroll, 300vh);   /* runway: more = slower scrub */
  background: #000;                    /* pure black to match the frame backgrounds */
}

.seq__pin {
  position: sticky;
  top: 0;
  height: 100vh;
  height: 100svh;                      /* respects mobile browser chrome */
  display: grid;
  place-items: center;
  overflow: clip;
}

.seq__canvas {
  width: 100%;
  height: 100%;
}

/* Copy overlaid on the pinned stage. The overlay lives INSIDE .seq__pin so it
   overlaps the canvas (a sibling after the pin would start below the fold).
   Captions are absolutely placed and toggled .in at scroll depth. */
.seq__overlay {
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
}

@media (max-width: 640px) {
  /* Shorter runway on mobile: fewer frames, quicker scrub, less scrolling. */
  .seq { height: var(--seq-scroll-mobile, 220vh); }
}