// text size
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 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 changeFontSize(sizeDifference){
  fs=getCookie('fs');
  newfs="";
  if (fs==""){
	fs=12;  
  }
  if (sizeDifference==2 && parseInt(fs)<20){
	newfs=parseInt(fs)+2;
  } else if (sizeDifference==-2 && parseInt(fs)>8){
	newfs=parseInt(fs)-2;
  } else if (sizeDifference==0){
	newfs=12;
  }
  if (newfs!=""){
  	document.getElementById('mainTD').style.fontSize=parseInt(newfs)+'px';
  	setCookie('fs',newfs,365);
  }
}

fs=getCookie('fs');
if (fs==null){
  setCookie('fs',12,365);
} else {
  document.write("<style>#mainTD{font-size:"+parseInt(fs)+"px;}</style>");
}