// sichtbarer Layer
var activeLayer = '';

function init() {
  activeLayer = '';
}

// Layer ein/ausschalten Funktion
function maus_layer(ebene) {
 if (document.layers) {	//  fuer NS4
	if (activeLayer != '')
		//Im Frame:
		//parent.inhalt.document.layers[activeLayer].visibility = 'hide';
		self.document.layers[activeLayer].visibility = 'hide';
 	if (activeLayer != ebene) 
    //Im Frame:
		//parent.inhalt.document.layers[ebene].visibility = 'show';
		self.document.layers[ebene].visibility = 'show';
 }
 else if (document.all) { // fuer IE
 	if (activeLayer != '')
		//Im Frame:
		//parent.inhalt.document.all[activeLayer].style.visibility = 'hidden';
		self.document.all[activeLayer].style.visibility = 'hidden';
 	if (activeLayer != ebene)
		//Im Frame:
		//parent.inhalt.document.all[ebene].style.visibility = 'visible';
		self.document.all[ebene].style.visibility = 'visible';
 }
 else if (document.getElementById) { // fuer Mozillanasen ;-)
	if (activeLayer != '')
		//Im Frame:
		//parent.inhalt.document.getElementById(activeLayer).style.visibility = 'hidden';
		self.document.getElementById(activeLayer).style.visibility = 'hidden';
 	if (activeLayer != ebene) 
		//Im Frame:
		//parent.inhalt.document.getElementById(ebene).style.visibility = 'visible';
		self.document.getElementById(ebene).style.visibility = 'visible';
 }
 activeLayer = (activeLayer == ebene) ? '' : ebene;
}