Hi all, please see the code and show me what I am doing wrong, my goal is to have a position: fixed;, header and position : fixed; right column, the left column and footer will be scrollable, whenever I place the property "fixed" on the header and right column I break the html markup, my original understanding is that all fixed or absolutely positioned elements must come after the scrollable elements, can someone point out what I am doing wrong with the included code, I have moved the elements around up, down and sideways to no avail. Although I am not applying the properties in the following code that are required for the design to allow a fixed header and right column. The example is the most rational of all my iterations, although the right column is not behaving... (And yes, I know, I know just enough to be dangerous) .

Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>header footer right col fixed, left scrollable</title>
<style type='text/css'>
html body {
   padding: 0px;
   margin: 0px;
   }
.wrapper{
   margin: 0px auto;
   width: 960px;
   height:100%;
   background-color: aqua
}
.header{

  top:0;
  left:0;
  width: 960px;
  height: 160px;
  background-color: purple
}
.left{
   float: left;   
   width: 710px;
   margin-right:710px;
   height: 100%;
   background-color: yellow
}
.right{
	float:right;
	position:fixed;
	top:160px;
	margin-left:-710px;
   width: 240px;
   height: 100%;   
   background-color: blue
}
.footer{
	float:left;
   width: 710px;
   margin-right:250px;
   height: 160px;
   background-color: purple
}
</style>
</head>
<body>
<div class="wrapper">
    <div class="header">
        header
    </div>
    
        <div class="left">
            left
        </div>
        <div class="right">
            right
        </div> 
    <div class="footer">
        footer
    </div>
</div>
</body>
</html>