if(window.addEventListener){
	window.addEventListener('load', gnav, false); 
}else{
	window.attachEvent('onload', function(){ gnav(); });
}

function gnav(){
	// first of all hide all the nested lists in the nav
	var u = document.getElementById('gnav').getElementsByTagName('ul');
	for(i=0;i<u.length;i++){
		u[i].style.display = 'none';
	}

	var a = document.getElementById('gnav').getElementsByTagName('a');
	for(z=0;z<a.length;z++){
		if(a[z].className == 'open'){
			// 'open' means always on (current section)
			var li = a[z].parentNode;
			var u = li.getElementsByTagName('ul')[0];
			u.style.display = 'block';
			a[z].onclick = function(){
				return false;
			}
		}

		// 'parent' means it toggles open/closed
		if(a[z].className == 'parent'){
			var li = a[z].parentNode;
			a[z].onclick = function(){
				li = this.parentNode;
				ul = li.getElementsByTagName('ul')[0];
				var ulStatus = (ul.style.display == 'none') ? 'block' : 'none';
				ul.style.display = ulStatus;
				return false;
			}
		}
	}
}