function setCookie(c_name,value,expiredays){
var exdate=new Date();
exdate.setDate(exdate.getDate()+expiredays);
document.cookie=c_name+ "=" +escape(value)+
((expiredays==null) ? "" : ";expires="+exdate.toGMTString());
}
function getCookie(c_name){
if (document.cookie.length>0){
  c_start=document.cookie.indexOf(c_name + "=");
  if (c_start!=-1){
    c_start=c_start + c_name.length+1;
    c_end=document.cookie.indexOf(";",c_start);
    if (c_end==-1) c_end=document.cookie.length;
    return unescape(document.cookie.substring(c_start,c_end));
    }
  }
return "";
}
function setFontSize(size) {
    setCookie('font-size', size, 30);
    $('body').css('font-size', size+'em');
}