function show(element){
   element.className += "hover";
}
function hide(element){
   element.className = element.className = "";
}

function popUp(URL) {
var browserwidth = document.body.offsetWidth;
var diff = (browserwidth - 860)/2;
if(diff<0){diff=0;}
var myX = diff + 430;

var idkontakt = window.open(URL, "Kontakt", "toolbar=0,scrollbars=0,location=0,status=0,menubar=0,resizable=0,width=450,height=600,left="+myX+",top=160,screenX="+myX+",scrennY=160");
}