function Is() {
    agent      = navigator.userAgent.toLowerCase();
    this.mac   = (agent.indexOf("mac")        !=   -1);
    this.major = parseInt(navigator.appVersion);
    this.minor = parseFloat(navigator.appVersion);
    this.ns    = ((agent.indexOf('mozilla')   !=   -1) &&
((agent.indexOf('spoofer')   ==   -1) &&
(agent.indexOf('compatible') ==   -1)));
    this.ns2   = (this.ns && (this.major      ==    3));
    this.ns3   = (this.ns && (this.major      ==    3));
    this.ns4b  = (this.ns && (this.major      ==    4) &&
(this.minor                  <= 4.03));
    this.ns4   = (this.ns && (this.major      ==    4));
    this.ns6   = (this.ns && (this.major     >=    5));
    this.ie    = (agent.indexOf("msie")       !=   -1);
    this.ie3   = (this.ie && (this.major      < 4));
    this.ie4   = (this.ie && (this.major      ==    4) &&
(agent.indexOf("msie 5.0")   ==   -1));
    this.ie5   = (this.ie && (this.major      ==    4) &&
(agent.indexOf("msie 5.0")   !=   -1));
    this.ie55  = (this.ie && (this.major      >=    4) &&
(agent.indexOf("msie 5.5")   !=   -1));
    this.aol   = (agent.indexOf("aol")        !=   -1);
    this.aol3  = (this.aol && this.ie3);
    this.aol4  = (this.aol && this.ie4);
    this.aol5  = (this.aol && this.ie5);
}

var is = new Is();
if(is.ns4) {
    doc = "document";
    sty = "";
    htm = ".document"
} else if(is.ie4) {
    doc = "document.all";
    sty = ".style";
    htm = ""
} else if(is.ns6) {
    doc = "document.getElementById";
    sty = ".style";
    htm = ".document"

}
// *****************************************

var referenciaEstilo;
var capaVisible;
var navegador;
if (is.ns4) {
  referenciaEstilo = "";
  capaVisible="show";
  navegador = "Netscape4"; }
else if(is.ns6) {
  referenciaEstilo = "";
  capaVisible="visible";
  navegador = "Net6"; }
else if(is.ie) {
  referenciaEstilo = "style.";
  capaVisible="visible";
  navegador = "Explorer"; }



function referenciaCapa(nombreCapa) {

  if (navegador=="Netscape4"){
    return "document.layers['"+nombreCapa+"'].";}

  else if(navegador=="Net6") {
    return document.getElementById("nombreCapa");}

else if(navegador=="Explorer")
    return "document.all['"+nombreCapa+"'].";
}

function referenciaPixels(pixels) {
  if (navegador=="Netscape")
    return parseInt(pixels);
  else
    return "'"+pixels+"px'";
}
function inicio() {
nombreCapa="inicial";
nombreviejo=nombreCapa;
cerrarCapas(nombreviejo);
}

function cerrarCapas(nombreviejo){
if(is.ns6){
document.getElementById(nombreviejo).style.visibility = "hidden" }
else{eval(referenciaCapa(nombreviejo)+referenciaEstilo+'visibility = "hidden"');}
}

function mostrarCapa(nombreCapa){
if (nombreCapa=="voyfotos") return(location.href="planofotos.htm");
cerrarCapas(nombreviejo);
if(is.ns6){
document.getElementById(nombreCapa).style.visibility = "visible" }
nombreviejo=nombreCapa;
return(eval(referenciaCapa(nombreCapa)+referenciaEstilo+'visibility = "visible"'));
}

function muestra(lacapa){
eval(referenciaCapa(lacapa)+referenciaEstilo+'visibility = "visible"');
}
function cierra(lacapa){
eval(referenciaCapa(lacapa)+referenciaEstilo+'visibility = "hidden"');
}
function info(){
  Ventana=open("como.htm","como","toolbar=no,directories=no,menubar=no,status=no,resizable=no,scrollbars=yes,width=450,height=400");
}
function correo(){
  Ventana2=open("../varios/direccion.htm","direccion","toolbar=no,directories=no,menubar=no,status=no,resizable=no,scrollbars=yes,width=450,height=400");
}
if (parseInt(navigator.appVersion) < 4 ) alert("Necesitas Netscape o Explorer versión 4 o superior\nYou need Netscape or Explorer version 4 or later");
 else if (navigator.appName == "Microsoft Internet Explorer" && parseInt(navigator.appVersion) < 4.0) alert("Necesitas Netscape o Explorer versión 4 o superior\nYou need Netscape or Explorer version 4 or later");