You should call files into your main html, for example
<link rel="stylesheet" href="ajax.navigate.min.css">
<script type="text/javascript" src="ajax.navigate.min.js"></script>
<a href="sub.html" class="ajax-navigate" data-direction="right">Sub Page</a>
<a href="sub-2.html" class="ajax-navigate">Sub 2 Page</a>
<button class="ajax-navigate-close" data-direction="down">back</button>