/**
 * Sticky footer
 */
body {
	height: 100%;
	overflow: hidden;
	margin: 0;
}

#wrapper{
      min-height:50%;
      height:50%;
      background: yellow;
      position: absolute;
      width: 100%;
}
 #footer{
      background:red;
      width: 100%;
}
#footer, #push{
      height:30%;
      margin-top: 50%;/* height of the wrapper */
      position: absolute;
}