function setFontSize(size,line) {
  
   var div = document.getElementsByTagName('div');
   for(i=0; i < div.length; i++) {
   	  if (div[i].id == 'content_middle') {
   	  	div[i].style.fontSize = size + "%";
				div[i].style.lineHeight = (line/10) + "em"
				
				}
   }
   

				
				
}