CodePen

HTML

            
              <div id="wrap">
<div id="header">
  <div class="left">this is header</div>
  <div class="right">
    this is header right
  </div>
</div>

<div id="content">
   <div class="left">this is content</div>
  <div class="right">
    this is content right
  </div>
</div>

<div id="footer">
   <div class="left">this is footer</div>
  <div class="right">
    this is footer right
  </div>
</div>
</div>
            
          
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CSS

            
              #wrap {
  width: 960px;
  margin: 0 auto;
}
div {
  border: 1px solid silver
}

.right {
  float: right
    width: 300px;
}
.left {
  width: 650px;
  float: left;
}
            
          
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JS

            
              
            
          
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