var browserVersion = parseInt(navigator.appVersion);
var browserName = navigator.appName;
var browserNN4 = (document.layers) ? true : false;
var browserNN5 = ((browserName == "Netscape") && (browserVersion >= 5)) ? true : false;
var browserIE4 = (document.all) ? true : false;
var browserOpera = (navigator.userAgent.indexOf('Opera') != -1);
var vis = (browserNN4) ? ".visibility=\"show\"" : ".visibility=\"visible\"";
var unvis = (browserNN4) ? ".visibility=\"hide\"" : ".visibility=\"hidden\"";
var isvis = (browserNN4) ? ".visibility==\"show\"" : ".visibility==\"visible\"";
var block = ".display=\"block\"";
var unblock = ".display=\"none\"";
var isblk = ".display==\"block\"";

var layerRef = "document.getElementById('";
var styleSwitch="').style";
var styleSwitch2 = "')";
 
if (browserNN4) {
	//alert('NN4');
	layerRef = "document.layers['";
	styleSwitch = "']";
	styleSwitch2 = "']";
} 
if (browserIE4) {
	layerRef = "document.all['";
	styleSwitch = "'].style";
	styleSwitch2 = "']";
}
if (browserNN5) {
	//alert("nn5");
	layerRef = "document.getElementById('";
	styleSwitch="').style";
	styleSwitch2 = "')";
}

function MakeVisible(layerName) {
	eval(layerRef+layerName+styleSwitch+vis);
}

function MakeUnvisible(layerName) {
	eval(layerRef+layerName+styleSwitch+unvis);
}

function IsVisible(layerName) {
	return eval(layerRef+layerName+styleSwitch+isvis);
}

function DisplayBlock(layerName) {
	return eval(layerRef+layerName+styleSwitch+block);
}

function HideBlock(layerName) {
	return eval(layerRef+layerName+styleSwitch+unblock);
}

function IsBlock(layerName) {
	return eval(layerRef+layerName+styleSwitch+isblk);
}

function AlignLayer(work_layer, base_layer) {
	eval(layerRef+work_layer+styleSwitch+'.top = 687');
	eval(layerRef+work_layer+styleSwitch+'.left = '+ layerRef+base_layer+styleSwitch2+'.offsetLeft');
}