function show_visibility(IDS){
	hide_visibility();
	document.getElementById(IDS).style.display = 'block';
}

function hide_visibility(){
	var sel = document.getElementById('leftNavFrame').getElementsByTagName('div');
	for (var i=0; i<sel.length; i++) { 
		sel[i].style.display = 'none'; 
	}
}

function show_background(IDS){
	hide_background();
/*	document.getElementById(IDS).style.display = 'block'; */
	document.getElementById(IDS).className = "triggerActive";
}

function hide_background(){
	var sel = document.getElementById('leftNavItems').getElementsByTagName('div');
	for (var q=0; q<sel.length; q++) { 
/*		sel[q].style.display = 'none'; */
		sel[q].className = "trigger";		
	}
}