// controls main nav rollovers
	function toggle_nav (n) {
		off = document.getElementById("nav" + n + "off");
		on  = document.getElementById("nav" + n + "on");

		if(on.style.display == "none") {
			on.style.display = "block";
			off.style.display = "none";
		}
		else {
			on.style.display = "none";
			off.style.display = "block";
		}
	}