Set Horizontal and Vertical scroll bar for TinyMCE editor in ASP.Net

<style type="text/css">
    .ScrollBar
    {
        max-width: 400px;
        max-height: 200px;
        overflow-x: scroll;
        overflow-y: scroll;
    }
</style>
<script type="text/javascript" src="//tinymce.cachefly.net/4.0/tinymce.min.js"></script>
<script type="text/javascript">
    tinymce.init({
        selector: 'textarea',
        width: 500,
        height: 300,
        resize: false
    });
</script>
<div class="ScrollBar">
    <textarea name="txtHTMLContent" rows="2" cols="20" id="txtHTMLContent"></textarea>
</div>