browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);
var ns = (browserName == "Netscape" && browserVer <5);
var ns6 = (browserName == "Netscape" && browserVer == 5);
var ie = (browserName == "Microsoft Internet Explorer");
var mac = (navigator.userAgent.indexOf("Mac") != -1);

function visible(lelayer){
/*if (ns){document.layers[lelayer].visibility = "show";}
else if (ie){document.all[lelayer].style.visibility = "visible";}
else if (ns6){document.getElementById(lelayer).style.visibility = "visible";}*/
document.getElementById(lelayer).style.display = "block"
}
function invisible(lelayer){
document.getElementById(lelayer).style.display = "none"
}