<script>
$(window).on('action:widgets.loaded', function() {
  if (!$('li.lights-out').length) {
    var panel = $('<li class="lights-out"><a title="" href="#" data-original-title="Dark Theme"><i class="fa fa-fw fa-lightbulb-o"></i><span class="visible-xs-inline">Dark Theme</span></a></li>');
    $('ul#logged-in-menu').prepend(panel);
    $('ul#logged-out-menu').prepend(panel);
    panel.on('click', function() {
    enabled = !$('body').hasClass('lights-out');
    $('body').toggleClass('lights-out',  enabled);
    localStorage.setItem('user:theme', enabled ?  'lights-out' : '');
    });
  }
});
</script>


<script>
$('document').ready(function() {
    var theme = localStorage.getItem('user:theme');
    if (theme) {
        $('body').addClass(theme );
    }
});
</script>