function plaetten()
  {
  document.getElementById("menv").style.visibility = "hidden";
  document.getElementById("menw").style.visibility = "hidden";
  document.getElementById("menwe").style.visibility = "hidden";
  }

function inder(opfer)
  {
  plaetten();
  document.getElementById(opfer).style.visibility = "visible";
  }

function neufenster(zieldatei,breite,hoehe)
 {
 window.open(zieldatei,"popup","width=" + breite + ",height=" + hoehe + ",screenX=40,left=40,screenY=200,top=200,scrollbars=no,resizable=yes");
 }

function biofenster(zieldatei)
 {
 var bildbreite = screen.width;
 var bildhoehe = screen.height;
 var vermit = (bildhoehe - 360) / 2;
 var hormit = (bildbreite - 560) / 2;
 window.open(zieldatei,"biopop","width=560,height=360,screenX=" + hormit + ",left=" + hormit + ",screenY=" + vermit + ",top=" + vermit + ",scrollbars=yes,resizable=yes");
 }

 /*
 Mehrzeiliger
 Kommentar
 */