/* V47 — selected Monolite material, symmetric inset rails. Only this overlay moves. */
.chapter-shutter-left,.opening-shutter--left{
  clip-path:none;
  background:#0b0c0e url('transition-assets/monolith-black-laser-v55-4k.webp') center/cover no-repeat;
  will-change:transform;
}
.opening-shutter--left{transform:translateX(101%)}
.chapter-shutter-right,.opening-shutter--right,.chapter-edge,.opening-shutter-edge{display:none!important}
/* Recompose the two original edge rails above the central cover crop.
   Each rail renders the SAME complete asset at height:100%, with width:auto:
   source details keep their aspect ratio and their original 46.7% vertical anchor.
   Only its outer slice is visible. A short inner feather merges into the steel.
   Both rails use the same left slice (mirrored on the right), avoiding source
   asymmetry. 1px compensates the panel overscan; 3px keeps the glow inside. */
.chapter-shutter-left::before,.chapter-shutter-left::after,
.opening-shutter--left::before,.opening-shutter--left::after{
  content:"";
  display:block!important;
  position:absolute;
  top:0;bottom:0;
  width:max(18px,2.5vh);
  clip-path:none;
  background-image:url('transition-assets/monolith.png');
  background-size:auto 100%;
  background-repeat:no-repeat;
  opacity:1;
  pointer-events:none;
}
.chapter-shutter-left::before,.opening-shutter--left::before{
  left:4px;right:auto;
  background-position:left center;
  -webkit-mask-image:linear-gradient(to right,#000 0%,#000 72%,transparent 100%);
  mask-image:linear-gradient(to right,#000 0%,#000 72%,transparent 100%);
}
.chapter-shutter-left::after,.opening-shutter--left::after{
  right:4px;left:auto;
  background-position:left center;
  transform:scaleX(-1);
  -webkit-mask-image:linear-gradient(to right,#000 0%,#000 72%,transparent 100%);
  mask-image:linear-gradient(to right,#000 0%,#000 72%,transparent 100%);
}
/* Wide viewports retain the original full-width edges under cover already. */
@media(min-aspect-ratio:3/4){
  .chapter-shutter-left::before,.chapter-shutter-left::after,
  .opening-shutter--left::before,.opening-shutter--left::after{display:none!important}
}
@media(prefers-reduced-motion:reduce){
  .chapter-shutter-left,.opening-shutter--left{will-change:auto}
  .chapter-curtain{background:#000}
}