function click_menu(id){
 
 	el=document.getElementById(id);
	
	
	if (el.className=='invisible') {
		el.className='visible';
		SetCookie(id,1,1);
	}
		
	else {
		el.className='invisible';
		SetCookie(id,0,1);
		}
 
 }
 
 function SetCookie(cookieName,cookieValue,nDays) {
 var today = new Date();
 var expire = new Date();
 if (nDays==null) nDays=1;
 expire.setTime(today.getTime() + 3600000*24*nDays);
 document.cookie = cookieName+"="+escape(cookieValue)
                 + ";expires="+expire.toGMTString()+";PATH=/;";
}