function mostrarCapa(capa) {
	$(capa).style.height = Element.getDimensions($('wrapper')).height  - 78; // 78 és una alçada que li hem de restar
	// sembla que el style.height no funciona amb Firefox
	$(capa).style.visibility = "visible";
}
function ocultarCapa(capa) {
	$(capa).style.visibility = "hidden";
}
function cambiarFondo(capa,imagen) {
	$(capa).style.backgroundImage = "url("+imagen+")";	
}
var lastcapa = "";
function escondeSbmn(id) {
	if(lastcapa != "") {
		$(lastcapa).style.visibility = "hidden";
	}
	$('sbmnSecciones').style.zIndex = -1;
	lastcapa = id;
}
function visualizaSbmn(idcapa) {
	escondeSbmn(idcapa);
	$(idcapa).style.visibility = "visible";
	$('sbmnSecciones').style.zIndex = 5000;
}
function Slide(){
	mostrarCapa('slide');
	cargar_contenido();
}
function Oculta(){
	ocultarCapa('slide');
}
function XHConn()
{
    var xmlhttp, bComplete = false;
    try { xmlhttp = new ActiveXObject("Msxml2.XMLHTTP"); }
    catch (e) { try { xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); }
    catch (e) { try { xmlhttp = new XMLHttpRequest(); }
    catch (e) { xmlhttp = false; }}}
    if (!xmlhttp) return null;
    this.connect = function(sURL, sMethod, sVars, fnDone)
    {
        if (!xmlhttp) return false;
        bComplete = false;
        sMethod = sMethod.toUpperCase();

        try {
            if (sMethod == "GET")
            {
                xmlhttp.open(sMethod, sURL+"?"+sVars, true);
                sVars = "";
            }
            else
            {
                xmlhttp.open(sMethod, sURL, true);
                xmlhttp.setRequestHeader("Method", "POST "+sURL+" HTTP/1.1");
                xmlhttp.setRequestHeader("Content-Type",
                    "application/x-www-form-urlencoded");
            }
            xmlhttp.onreadystatechange = function(){
                if (xmlhttp.readyState == 4 && !bComplete)
                {
                    bComplete = true;
                    fnDone(xmlhttp);
                }};
            xmlhttp.send(sVars);
        }
        catch(z) { return false; }
        return true;
    };
    return this;
}
function is_email(str) {
  var regExpr = /^[0-9a-z\-\_]+(.[0-9a-z\-\_]+)*@[0-9a-z\-]+(.[0-9a-z\-]+)*\.[0-9a-z][0-9a-z]+$/;
  return regExpr.test(str.toLowerCase());
}