Div side by side display perfect solution

Div side-by-side display perfect solution ~
It's really easy to use.
CSS:
# Mainbg {
Float: left;
Width: 750px;
Margin: 0;
Padding: 0;
Background: URL ("mainbg.gif") Repeat-y top left;
}
# Left {
Float: left;
Width: 150px;
Margin: 0;
Padding: 0;
Background: #333;
}
# Right {
Float: left;
Width: 600px;
Margin: 0;
Padding: 0;
Background: #666;
}

HTML section:
<Div id = "mainbg">
<Div id = "Left"> content on the left </div>
<Div id = "right"> content on the right </div>
</Div>

This leftt and rightare nested in a divblock named mainbg. mainbg.gif is a horizontal straight line with a length of 150 PX. The first 600 pixels are the same color as the left background, and the last pixels are the same color as the right side.

In this way, the blank space under the two short blocks will be added by the same background color. Creates an illusion of the same height. Hey. .