Adaptive layout with an absolute positioning height of 100%

The container height of 100% is frequently used. Any container can be implemented without nested relationships.
Think of the body as a container and set its height to 100% as the upper-layer label of the internal object.
Basic example
* {Margin: 0; padding: 0; border: 0 ;}
Html, body {height: 100%;}/* both set html to be compatible with FF */
# Box_2 {height: 100%; background: #000 ;}
Absolute overlapping height
# Box_1 {position: absolute; top: 0; left: 0; width: 100%; height: 50px; background: # f00; z-index: 2 ;}
# Box_2 {position: absolute; left: 0; top: 0; width: 100%; height: 100%; background: #000; z-index: 1 ;}
Vertical and relative height
# Box_1 {position: absolute; top: 0; left: 0; width: 100%; height: 30%; background: # f00; z-index: 2 ;}
# Box_2 {position: absolute; left: 0; top: 30%; width: 100%; height: 70%; background: #000; z-index: 1 ;}
Horizontal relative width
# Box_1 {position: absolute; top: 0; left: 0; width: 40%; height: 100%; background: # f00; z-index: 2 ;}
# Box_2 {position: absolute; top: 0; right: 0; width: 60%; height: 100%; background: #000; z-index: 1 ;}
This layout does not require float, and there are many changes:
1, N column layout
2, N rows layout
3, N columns plus N rows cross layout
It is worth noting that when you browse the container page of the relative size under FF, the container size is adjusted in real time while the IE is only effective after the window is adjusted.
IE5.0/IE5.5/IE6.0 and FF1.5 passed the test.