Set default selected language for Google Translate API in JavaScript

hello,

i am using google translator api it has lots of language i want when page load by default it should select spanish language.

<style>
    .goog-te-gadget-simple
    {
        padding: 0px !important;
        line-height: 1.428571429;
        color: #555555;
        vertical-align: middle;
        background-color: #fff;
        border: 1px solid #a5a5a599;
        border-radius: 4px;
        width: 100%;
        float: right;
        margin-top: -4px;
    }
    .goog-te-banner-frame.skiptranslate
    {
        display: none !important;
    }
    body
    {
        top: 0px !important;
    }        
    .goog-te-gadget-icon
    {
        background: none !important;
        display: none;
    }        
    .goog-te-gadget-simple .goog-te-menu-value
    {
        color: #000;
        font-size: 12px;
        font-family: 'Open Sans' , sans-serif;
    }
</style>
<div id="google_translate_element">
</div>
<script type="text/javascript">
    function googleTranslateElementInit() {
        new google.translate.TranslateElement({
            pageLanguage: 'en',
            layout: google.translate.TranslateElement.InlineLayout.SIMPLE
        }, 'google_translate_element');
    }
</script>
<script type="text/javascript" src="//translate.google.com/translate_a/element.js?cb=googleTranslateElementInit"></script>