body
  {
  margin: 0;
  padding: 0;
  }
div#Menu
  {
  position: fixed;
  top: 0;
  left: 0;
  width: 270px;
  height: 100%;
  }
  
div#content { 
  position: absolute;
  top: 0;
  left: 270px;
  width: 750px;
    height: 100%;
 }