---
root:
  items:
    - type: stacking-context
      bounds: 50 50 100 100
      items:
        - type: rect
          bounds: 0 0 100 100
          color: black
        - type: rect
          bounds: 100 0 100 100
          color: red
        - type: rect
          bounds: 100 100 100 100
          color: green
        - type: rect
          bounds: 0 100 100 100
          color: blue