tam istediğinizi anlayamasamda şöyle bişey olabilir belki diye düşündüm ...
<!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" lang="en" xml:lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Dynamic Drive: CSS Liquid Layout #3.5- (Fluid-Fluid-Fixed)</title>
<style type="text/css">
body{
margin:0;
padding:0;
line-height: 1.5em;
}
b{font-size: 110%;}
em{color: red;}
#topsection{
width:600px;
background: #EAEAEA;
height: 90px;
}
#topsection h1{
margin: 0;
padding-top: 15px;
}
#maincontainer{
width:100%;
}
#contentwrapper{
margin-top:-90px;
float: right;
width: 200px;
}
#contentcolumn{
margin: 0 20px 0 0px
}
#leftcolumn{
width: 600px;
background: #C8FC98;
}
#rightcolumn{
width: 600px;
background: #FDE95E;
}
#footer{
clear: both;
width: 100%;
background: black;
color: #FFF;
text-align: center;
padding: 4px 0;
}
#footer a{
color: #FFFF80;
}
.innertube{
margin: 10px;
margin-top: 0;
}
</style>
<script type="text/javascript">
var gibberish=["This is just some filler text", "Welcome to Dynamic Drive CSS Library", "Demo content nothing to read here"]
function filltext(words){
for (var i=0; i<words; i++)
document.write(gibberish[Math.floor(Math.random()*3)]+" ")
}
</script>
</head>
<body>
<div id="maincontainer">
<div id="topsection"><div class="innertube"><h1>CSS Liquid Layout #3.5- (Fluid-Fluid-Fixed)</h1></div></div>
<div id="contentwrapper">
<div id="contentcolumn">
<div class="innertube"><b>Content Column: <em>Fluid</em></b> <script type="text/javascript">filltext(45)</script></div>
</div>
</div>
<div id="leftcolumn">
<div class="innertube"><b>Left Column: <em>20%</em></b> <script type="text/javascript">filltext(20)</script></div>
</div>
<div id="rightcolumn">
<div class="innertube"><b>Right Column: <em>180px</em></b> <script type="text/javascript">filltext(15)</script></div>
</div>
<div id="footer"><a href="http://www.dynamicdrive.com/style/">Dynamic Drive CSS Library</a></div>
</div>
</body>
</html>