function toggleMenu(num)
{
	var obj = document.getElementById("nav" + num);

	if(obj.style.display == "block" || obj.style.display == "")
	{
		// Collapse menu
		obj.style.display = "none";
	}
	else
	{
		// Expand menu
		obj.style.display = "block";
	}
}

function Bildwechsel1(id) {
 	window.document.getElementById(id).src = Highlight1.src;
}

function Bildwechsel2(id) {
 	window.document.getElementById(id).src = Normal1.src;
}

function markeNav(id) {
	window.document.getElementById(id).style = 'font-weight:bold';	
}