body{
  margin:0;
  padding:30px 0 0 0;
 } 
 div#header{
  position:absolute; top:0;
  left:0;
  width:100%;
  height:30px;
 }
 @media screen{
  body>div#header{
   position:fixed;
  }
 }
 * html body{
  overflow:hidden;
 } 
 * html div#content{
  height:100%;
  overflow:auto;
 }