CSS 2 div size auto same height

Question

i have an question in CSS:

How i can do that:

When the green div has (auto)

Answer 1

First, read this excellent article. Then, check out the fiddle:

http://jsfiddle.net/UnsungHero97/qUT3d/

HTML

    

        

            
Column 1
            
Column 2
            
Column 3
        
    

CSS

#container3 {
    float:left;
    width:100%;
    background:green;
    overflow:hidden;
    position:relative;
}
#container2 {
    float:left;
    width:100%;
    background:yellow;
    position:relative;
    right:30%;
}
#container1 {
    float:left;
    width:100%;
    background:red;
    position:relative;
    right:40%;
}
#col1 {
    float:left;
    width:26%;
    position:relative;
    left:72%;
    overflow:hidden;
}
#col2 {
    float:left;
    width:36%;
    position:relative;
    left:76%;
    overflow:hidden;
}
#col3 {
    float:left;
    width:26%;
    position:relative;
    left:80%;
    overflow:hidden;
}​