function get_randomCssNum()
{
	var kisonNo = readCookie2("CssNo");
	var ranCssNum;
	while(true)
	{
    	ranCssNum= Math.floor(Math.random()*3);
		//var ranCssNum= Math.floor(Math.random()*Number of CSS you Have);
		if(kisonNo==null) return ranCssNum;
		if((kisonNo=="0")||(kisonNo=="1")||(kisonNo=="2"))
		{
			if(ranCssNum!=parseInt(kisonNo,10)) break;
		}
		else break;
	}
    return ranCssNum;
}

function readCookie2(name) {
  var nameEQ = name + "=";
  var ca = document.cookie.split(';');
  for(var i=0;i < ca.length;i++) {
    var c = ca[i];
    while (c.charAt(0)==' ') c = c.substring(1,c.length);
    if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
  }
  return null;
}

function createCookie(name,value,days) {
  if (days) {
    var date = new Date();
    date.setTime(date.getTime()+(days*24*60*60*1000));
    var expires = "; expires="+date.toGMTString();
  }
  else expires = "";
  document.cookie = name+"="+value+expires+"; path=/";

	var cssName = "style01.css";
	if(value != null )
	{
		switch(value)
		{
			case 0:
				cssName = "style01.css";
				break;
			case 1:
				cssName = "style02.css";
				break;
			case 2:
				cssName = "style03.css";
				break;
		}
	}
	var urlCss="<link rel='stylesheet' type='text/css' href='" + cssName + "'>";
	return urlCss;
}

var ranCssNo = get_randomCssNum();
document.write(createCookie("CssNo",ranCssNo, 7));