<!-- 
if (document.getElementById) { window.onload = swap };
function swap() {
var numimages=3;
rndimg = new Array("http://www.avatar.czfilmy.cz/wp-content/themes/avatar/images/bg.jpg", "http://www.avatar.czfilmy.cz/wp-content/themes/avatar/images/bg2.jpg", "http://www.avatar.czfilmy.cz/wp-content/themes/avatar/images/bg3.jpg"); 
x=(Math.floor(Math.random()*numimages));
randomimage=(rndimg[x]);
document.getElementById("logonove").style.backgroundImage = "url("+ randomimage +")"; 
}
//-->