function FensterOeffnen (Adresse, width, height) {
  var groesse = getWinSize();
  var breite = width;
  var hoehe = height;

  var links = (groesse.w/2-breite/2);
  MeinFenster = window.open(Adresse, "Bestellung", "width="+breite+",height="+hoehe+",scrollbars=yes,left="+links+",top=144");

  MeinFenster.focus();
}
function getWinSize(){
	var size = {w:0 ,h:0}
	var win = window;
	
	size.w = win.innerWidth ? win.innerWidth : win.document.body.clientWidth;
	size.h = win.innerHeight ? win.innerHeight : win.document.body.clientHeight;

	return size;
}