tn = false;
nb	=	false;
function toggleNav() {
	if(!tn) tn=document.getElementById('toggle_nav');
	if(!nb) nb=document.getElementById('nav2_box');
	if(nb.className=='box_invisible') {
		nb.className = 'box';
		tn.innerHTML='verbergen';	
		saveCookie('nav=v');
	} else {
		nb.className = 'box_invisible';
		tn.innerHTML='anzeigen';	
		saveCookie('nav=h');
	}
}

function saveCookie(data) {
	cdata		 = data.split('=');
	ccontent = document.cookie.split(',');
	expire	 = new Date();
	expireDate	=	expire.getTime() + (30 * 24 * 60 * 60 * 1000);
	expire.setTime(expireDate)
	document.cookie = data+'; expires='+expire.toGMTString();
}