function blanket_size() {

	if (typeof window.innerWidth != 'undefined')
		{
      		 viewportheight = window.innerHeight;
 		}
 		else
 		{
     		  	 viewportheight = document.documentElement.clientHeight;
 		}
		if (viewportheight > document.body.parentNode.scrollHeight && viewportheight > document.body.parentNode.clientHeight)
		{
			blanket_height = viewportheight;
		}
		else
		{
			if (document.body.parentNode.clientHeight > document.body.parentNode.scrollHeight)
			{
				blanket_height = document.body.parentNode.clientHeight;
			}
			else
			{
				blanket_height = document.body.parentNode.scrollHeight;
			}
		}
		
		var blanket = document.getElementById('blanket');
    		blanket.style.height = blanket_height + 'px';


	}