<!-- // Mostrar ocultar capas	

var visto = null;
function verCapa(iden) {
  obj = document.getElementById(iden);
  if (obj==visto) return false;
  if (visto!=null)
    visto.style.visibility = 'hidden';
  obj.style.visibility = 'visible';
  visto=obj;
}

<!-- //  	

var altura = 0;
var velocidad = 10;

function nuevoAjax() {
	var objetoAjax = false;
	
	try {
		// Navegadores distintos a Internet Explorer
		objetoAjax = new ActiveXObject("Msxml2.XMLHTTP");
	}
	catch (e) {
		try {
			// Para Explorer
			objetoAjax = new ActiveXObject("Microsoft.XMLHTTP");
		}
		catch (E) {
			objetoAjax = false;
		}
	}

	if (!objetoAjax && typeof XMLHttpRequest!='undefined') {
		objetoAjax = new XMLHttpRequest();
	}

	return objetoAjax;
}

function cargarURL(url) {
	if(url=="index.php")
		window.open('http://www.imaginacs.com');
	ajax = nuevoAjax();
	capaResultado = document.getElementById("centralDesplegable");
	
	ajax.open("GET", url, true);
	ajax.onreadystatechange = function() {
		if (ajax.readyState == 1) {
			capaResultado.innerHTML = "<p>Cargando........</p>";
		}
		else if (ajax.readyState == 4) {
			if (ajax.status == 200) {
				capaResultado.innerHTML = ajax.responseText;
			}
			else if (ajax.status == 404) {
				capaResultado.innerHTML = "La direccion no existe";
			}
			else {
				capaResultado.innerHTML = "Error: " + ajax.status;
			}
		}
	}
	ajax.send(null);	
}


function incrementarAltura() {
	capa = document.getElementById('centralDesplegable');
	altura += velocidad;
	if (!(altura >= 616)) {
		capa.style.height = altura + 'px';
		window.setTimeout("incrementarAltura();", 20);
	}
}

function extender(url) {
	objeto = document.getElementById('centralDesplegable');
	objeto.style.height = "0px";
	objeto.style.visibility = 'visible';
	incrementarAltura();
	
	//window.setTimeout("cargarURL('"+url+"')", 3000);
	cargarURL(url);
}

function contraer() {
	var objeto2 = document.getElementById('centralDesplegable');
	altura -= velocidad;
	if (!(altura <= 0)) {
		objeto2.style.height = altura + 'px';
		window.setTimeout ("contraer();", 20);
	}
	else {
		objeto2.style.visibility = 'hidden';
		objeto2.style.height = '0px';
	}
}

function extenderContraer(url) {
	if (altura <= 0)
		extender(url);
	else
		contraer();
}

<!-- // Formulario

function enviar_frm_contacta()
{
	error_message = "";
	
    if (document.frm_contacta.email.value.length==0)
	{
    	error_message = "- E-mail\n" + error_message;
    	document.frm_contacta.email.focus();
		document.frm_contacta.email.select();
    }

	if (document.frm_contacta.nombre.value.length==0)
	{
    	error_message = "- Nombre\n" + error_message;
    	document.frm_contacta.nombre.focus();
		document.frm_contacta.nombre.select();
    }

	if (error_message != "")
	{
		error_message = "Los siguientes campos son obligatorios:\n\n" + error_message;
		window.alert(error_message);
		return;
	}
	
	length_mail = document.frm_contacta.email.value.length;
	length_mail = length_mail - 1;
	if ( (document.frm_contacta.email.value.indexOf ('@', 0) < 1) || (document.frm_contacta.email.value.length < 5) 
		|| (document.frm_contacta.email.value.lastIndexOf(".") < 2) || (document.frm_contacta.email.value.charAt(length_mail) == "." ) )
	{ 
    	alert("Escriba una dirección de correo válida en el campo \"E-mail\".");
		document.frm_contacta.email.focus();
		document.frm_contacta.email.select();
    	return;
    }
    
	document.frm_contacta.submit();
	
}

<!-- // LOGOS CLIENTES CAMBIO IMG

if (document.images) {
			  
                 var logo01off = new Image()
                 logo01off.src = "img/logo01off.gif"
                 var logo01on = new Image()
                 logo01on.src = "img/logo01on.gif"
				 
				 var logo02off = new Image()
                 logo02off.src = "img/logo02off.gif"
                 var logo02on = new Image()
                 logo02on.src = "img/logo02on.gif"
				 
				  var logo03off = new Image()
                 logo03off.src = "img/logo03off.gif"
                 var logo03on = new Image()
                 logo03on.src = "img/logo03on.gif"
				 
				  var logo04off = new Image()
                 logo04off.src = "img/logo04off.gif"
                 var logo04on = new Image()
                 logo04on.src = "img/logo04on.gif"
				 
				var logo05off = new Image()
                 logo05off.src = "img/logo05off.gif"
                 var logo05on = new Image()
                 logo05on.src = "img/logo05on.gif"
				 
				 var logo06off = new Image()
                 logo06off.src = "img/logo06off.gif"
                 var logo06on = new Image()
                 logo06on.src = "img/logo06on.gif"

 				  var logo07off = new Image()
                 logo07off.src = "img/logo07off.gif"
                 var logo07on = new Image()
                 logo07on.src = "img/logo07on.gif"
				 
				  var logo08off = new Image()
                 logo08off.src = "img/logo08off.gif"
                 var logo08on = new Image()
                 logo08on.src = "img/logo08on.gif"
				 
				  var logo09off = new Image()
                 logo09off.src = "img/logo09off.gif"
                 var logo09on = new Image()
                 logo09on.src = "img/logo09on.gif"
				 
				  var logo10off = new Image()
                 logo10off.src = "img/logo10off.gif"
                 var logo10on = new Image()
                 logo10on.src = "img/logo10on.gif"
				 
				  var logo11off = new Image()
                 logo11off.src = "img/logo11off.gif"
                 var logo11on = new Image()
                 logo11on.src = "img/logo11on.gif"
				 
				  var logo12off = new Image()
                 logo12off.src = "img/logo12off.gif"
                 var logo12on = new Image()
                 logo12on.src = "img/logo12on.gif"
				 
				 var logo13off = new Image()
                 logo13off.src = "img/logo13off.gif"
                 var logo13on = new Image()
                 logo13on.src = "img/logo13on.gif"
				 
				 var logo14off = new Image()
                 logo14off.src = "img/logo14off.gif"
                 var logo14on = new Image()
                 logo14on.src = "img/logo14on.gif"
				 
				 var logo15off = new Image()
                 logo15off.src = "img/logo15off.gif"
                 var logo15on = new Image()
                 logo15on.src = "img/logo15on.gif"
				 
				 var logo16off = new Image()
                 logo16off.src = "img/logo16off.gif"
                 var logo16on = new Image()
                 logo16on.src = "img/logo16on.gif"
				 
				 var logo17off = new Image()
                 logo17off.src = "img/logo17off.gif"
                 var logo17on = new Image()
                 logo17on.src = "img/logo17on.gif"
				 
				 var logo18off = new Image()
                 logo18off.src = "img/logo18off.gif"
                 var logo18on = new Image()
                 logo18on.src = "img/logo18on.gif"
				 
				 var logo19off = new Image()
                 logo19off.src = "img/logo19off.gif"
                 var logo19on = new Image()
                 logo19on.src = "img/logo19on.gif"
				 
				 var logo20off = new Image()
                 logo20off.src = "img/logo20off.gif"
                 var logo20on = new Image()
                 logo20on.src = "img/logo20on.gif"
				 
				 var logo21off = new Image()
                 logo21off.src = "img/logo21off.gif"
                 var logo21on = new Image()
                 logo21on.src = "img/logo21on.gif"
				 
				 
				 
				 var bd01off = new Image()
                 bd01off.src = "img/bd01off.jpg"
                 var bd01on = new Image()
                 bd01on.src = "img/bd01on.jpg"
				 
				 var bd02off = new Image()
                 bd02off.src = "img/bd02off.jpg"
                 var bd02on = new Image()
                 bd02on.src = "img/bd02on.jpg"
				 
				 var bd03off = new Image()
                 bd03off.src = "img/bd03off.jpg"
                 var bd03on = new Image()
                 bd03on.src = "img/bd03on.jpg"
				 
				 var bd04off = new Image()
                 bd04off.src = "img/bd04off.jpg"
                 var bd04on = new Image()
                 bd04on.src = "img/bd04on.jpg"
				 
				 var bd05off = new Image()
                 bd05off.src = "img/bd05off.jpg"
                 var bd05on = new Image()
                 bd05on.src = "img/bd05on.jpg"


					  }
					  
                function inact(imgName) {
                if (document.images)
                  document[imgName].src = eval(imgName+'off.src')
                }
               function act(imgName) {
                if (document.images) 
                  document[imgName].src = eval(imgName+'on.src')
              }

