if(document.getElementById && document.all && document.styleSheets) {
  explorer_neu = 1;
} else {
  explorer_neu = 0;
}
if(navigator.appName.indexOf("Netscape") >= 0 && parseFloat(navigator.appVersion) < 5) {
  netscape_alt = 1;
} else {
  netscape_alt = 0;
}
if(document.getElementById && !document.all) {
  netscape_neu = 1;
} else {
  netscape_neu = 0;
}

/** darstellung **/

function navi_verstecken() {
  if ( explorer_neu || netscape_neu ) {
    document.getElementById("ausgabe").style.visibility = "hidden";
  }
  if (netscape_alt) {
    document.layers["ausgabe"].visibility = "hide";
  }
}

function navi_zeigen() {

  if (explorer_neu) {
    var x= ((document.body.clientWidth / 2) - 150);
	var y= 500;
    document.getElementById("ausgabe").style.left  = x;
    document.getElementById("ausgabe").style.top   = y;
    document.getElementById("ausgabe").style.visibility = "visible";
  }

  if (netscape_alt) {
//    if ( br.which==2 || br.which==3 ) {
//      var x  = (((window.innerWidth+window.pageXOffset) / 2) - 125);
//      var y  = 500;
//      document.layers["ausgabe"].moveTo(x, y);
//      document.layers["ausgabe"].visibility = "show";
//    }
  }
  if (netscape_neu) {
    var x  = (((window.innerWidth+window.pageXOffset) / 2) - 150);
    var y  = 500;
    document.getElementById("ausgabe").style.left = x + "px";
    document.getElementById("ausgabe").style.top = y + "px";
    document.getElementById("ausgabe").style.visibility = "visible";
  }
}