jQuery Nice Select Plugin with Position And OptGroup Support

Nice Select is a small plugin to show html select in stylish way. But there are some limitations such no optgroup support. And positioning is not supported yet. I come up with this two problems and below is the code a screenshot.

First download Nice Select plugin from link below:

https://drive.google.com/drive/folders/0B5nZNPW48dpFcjhqQTItSGkxMlk?usp=sharing

<link rel="stylesheet" type="text/css" href="nice-select.css"/>
<script src="jquery-2.1.1.min.js"></script>
<script src="jquery.nice-select.js"></script>
<script type="text/javascript">
    $(document).ready(function () {
        $("select").niceSelect();
    });
</script>