fill {
  child: transform {
    transform: translate3d(0, 0, 1);
    child: color {
      bounds: 0 0 50 50;
      color: rgb(0,255,0);
    }
  }
  path: "\
M 10 0\
L 40 0\
L 40 10\
L 50 10\
L 50 40\
L 40 40\
L 40 50\
L 10 50\
L 10 40\
L 0 40\
L 0 10\
L 10 10\
Z";
  fill-rule: winding;
}