function hideAllMenus(){ // hide all subnav menues
	var topmenus = getElementsByClass('topnav_link');
	var submenus = document.getElementById('subnav');
	for( var x = 0; x < submenus.childNodes.length; x++ ) {
		if (submenus.childNodes[x].nodeName == 'DIV') submenus.childNodes[x].style.visibility = 'hidden';
	}
	for( var y = 0; y < topmenus.length; y++ ) {
		topmenus[y].style.backgroundPosition = '0% 0px';
		topmenus[y].childNodes[0].style.backgroundPosition = '100% 0px';
	}
}
function showMenu(obj){
	var submenu = document.getElementById('subnav_' + obj);
	var topmenu = document.getElementById('topnav_' + obj);
	hideAllMenus();
	topmenu.style.backgroundPosition = '0% -33px';
	topmenu.childNodes[0].style.backgroundPosition = '100% -33px';
	if (submenu) submenu.style.visibility = 'visible';
}

function getElementsByClass(searchClass,node,tag) {
	var classElements = new Array();
	if ( node == null )
		node = document;
	if ( tag == null )
		tag = '*';
	var els = node.getElementsByTagName(tag);
	var elsLen = els.length;
	var pattern = new RegExp('(^|\\\\s)'+searchClass+'(\\\\s|$)');
	for (i = 0, j = 0; i < elsLen; i++) {
		if ( pattern.test(els[i].className) ) {
			classElements[j] = els[i];
			j++;
		}
	}
	return classElements;
}
function adjustTopNav(nav_sec){
	var section;
	switch (nav_sec){
		case "about":
			section = document.getElementById('topnav_1');
		break;
		case "products":
			section = document.getElementById('topnav_2');
		break;
		case "technology":
			section = document.getElementById('topnav_3');
		break;
		case "news_events":
			section = document.getElementById('topnav_4');
		break;
		case "support":
			section = document.getElementById('topnav_5');
		break;
		case "career":
			section = document.getElementById('topnav_6');
		break;
		default: break;
	}
	if (section) section.childNodes[0].style.color = '#9fcf67';
}