.media {
  position: relative;
  overflow: hidden;
  /* Optional global knobs */
  --parallax-direction: -1; /* 1 = normal, -1 = reversed */
  /* --parallax-strength: 90px;  If unset, JS auto-sizes per element */
}
.media > .img {
  position: absolute;
  height: calc(100% + var(--bleed, 0px) * 2);
  top: calc(-1 * var(--bleed, 0px));
  will-change: transform;
  transform: translate3d(0, 0, 0);
}

@media (prefers-reduced-motion: reduce) {
  .media > .img {
    transform: none !important;
  }
}