root:
  items:
    - type: stacking-context
      bounds: 0 0 300 100
      transform-style: flat
      perspective: 100
      items:
      - type: stacking-context
        bounds: 0 0 100 100
        transform-style: flat
        transform: rotate-y(-120)
        backface-visible: true
        items:
        - type: rect
          bounds: 0 0 100 100
          color: red