if you were looking at the error console you could see the answer by yourself
you have the javascript function which operates with document.getElementById('wrapper2') (twice in the code!! what for?)
<script type="text/javascript">
var scrollDiv = function(dir, px) {
var scroller = document.getElementById('wrapper2');
if (dir == 'l') {
scroller.scrollLeft -= px;
}
else if (dir == 'r') {
scroller.scrollLeft += px;
}
}
</script>
but you have no any element having this id