// var isNN4=false;
// var isIE4=false;
// var isDOM=false;
var isNN4, isIE4, isDOM;

var currentMenu = null;
var resetMenu = null;
var cellBGColour = "#000";
var menuBar = null;
var width = 0;
var catMenuWidth = 0;
var sectMenuWidth = 0;
var aboutMenuWidth =0;

function menuInit() {
	menuBar = document.getElementById("menuBar");
	resetMenu = document.getElementById("resetMenus");
}

function showCell(cell) {
	var currentCell = document.getElementById(cell);
	cellBGColour = currentCell.style.backgroundColor;
	currentCell.style.backgroundColor = "#000080"
	
	if (menuBar == null) menuInit();
}

function showMenu(menuLayer) {
	var requiredMenu = document.getElementById(menuLayer);
	if (requiredMenu != currentMenu) {
		if (currentMenu != null) currentMenu.style.visibility = "hidden"; 
		else resetMenu.style.visibility = "visible";

		requiredMenu.style.visibility = "visible";
		requiredMenu.style.right = "0px";
		currentMenu = requiredMenu;
	} else resetMenus();
}

function hideMenu(cell) {
	var currentCell = document.getElementById(cell);
	currentCell.style.backgroundColor = cellBGColour;
}

function resetMenus() {
	if (currentMenu != null) currentMenu.style.visibility = "hidden";
	currentMenu = null;
	resetMenu.style.visibility = "hidden";
}

function configureForBrowser() {
	if (isDOM) {
		if (menuBar == null) menuInit();
		menuBar.style.visibility = "visible";
	}
}