function usestyle()
{

  iArray=new Array(
	"/images/style1/style.css",
	"/images/style2/style.css",
	"/images/style3/style.css",
	"/images/style4/style.css"
  );

  ri=Math.floor(iArray.length*Math.random());
  ri="<link href='"+iArray[ri]+"' rel='stylesheet' type='text/css'>"
  document.write(ri);
}