Outer <div>:
Width: 100%

Height: 100%

Margin Top: 0%

Margin Left: 0%

Middle <div>:
Width: 50%

Height: 50%

Margin Top: 0%

Margin Left: 0%

Inner <div>:
Width: 50%

Height: 50%

Margin Top: 0%

Margin Left: 0%