3D CSS

    •
    A hallway viewed from a center top, 90 degree angle. 
    .scene {
  --rotation: 90deg;
  --perspective: 10cm;

  perspective: var(--perspective);
  perspective-origin: top center;
}

.hallway {
  transform-style: preserve-3d;
  rotate: x var(--rotation);
}

.door, .cliff {
  rotate: x calc(-1 * var(--rotation));
}

    For more examples, check out this 'lab' site I've created for experimenting with this technique.