// toggle nav visibility 

function toggle(targetId, ref){
	
  if (document.getElementById){
	
		var target = document.getElementById( targetId);
		var myRef = document.getElementById(ref);
	
		if (target.style.display == "none"){
			target.style.display = "";
			myRef.className = "selected";
		} else {
			target.style.display = "none";
			myRef.className = "deselected";
		}
  }
}