$('#scroll-trigger').click(function() {
          this.hide();
          var viewport = $('#container');
          $('#scroll-overlay')
            .css('left', viewport.css('left'))
            .css('top', viewport.css('top'))
            .css('width', viewport.width())
            .css('height', viewport.height())
            .css('z-index', 99)
            .css('display', '');