html,
body {
   margin:5px;
   padding:0;
   height:100%;
}
#container {
   min-height:100%;
   position:relative;
}
#header {
   background:#ff0;
   padding:10px;
}
#body {
   padding:10px;
   padding-bottom:60px;   /* Height of the footer */
}
#footer {
   position:absolute;
   bottom:0;
   width:100%;
   height:60px;   /* Height of the footer */
}

div.left {
    float: left;
    width: 50%;
}

div.right {
    float: right;
    width: 50%;
}