function openModalCalculator() {
    MOOdalBox.open(
    "CalculadoraCuota.html",
    "Cotizador de Viviendas Universales",
    "540 500");
}

function Querystring() {

    // get the query string, ignore the ? at the front.
    var querystring = location.search.substring(1, location.search.length);

    // parse out name/value pairs separated via &
    var args = querystring.split('&');

    // split out each name = value pair
    for (var i = 0; i < args.length; i++) {
        var pair = args[i].split('=');

        // Fix broken unescaping
        temp = unescape(pair[0]).split('+');
        name = temp.join(' ');

        temp = unescape(pair[1]).split('+');
        value = temp.join(' ');

        this[name] = value;
    }

    this.get = Querystring_get;
}

function Querystring_get(strKey, strDefault) {
    var value = this[strKey];
    
    if (value == null) {
        value = strDefault;
    }
    
    return value;
}