_includes/head.html

<meta charset="utf-8">

{% include seo.html %}

<link href="{% if site.atom_feed.path %}{{ site.atom_feed.path }}{% else %}{{ '/feed.xml' | absolute_url }}{% endif %}" type="application/atom+xml" rel="alternate" title="{{ site.title }} Feed">

<!-- http://t.co/dKP3o1e -->
<meta name="HandheldFriendly" content="True">
<meta name="MobileOptimized" content="320">
<meta name="viewport" content="width=device-width, initial-scale=1.0">

<script>
  document.documentElement.className = document.documentElement.className.replace(/\bno-js\b/g, '') + ' js ';
</script>
<script src="/assets/vendor/prism/clipboard.min.js"></script>
<script src="{{ '/assets/vendor/prism/prism.js' | absolute_url }}"></script>

<script type="text/javascript" async
  src="/assets/js/MathJax.js">
</script>

<link rel="stylesheet" href="/assets/css/bootstrap.min.css">

<script src="https://www.apachecon.com/event-images/snippet.js"></script>
<script src="/assets/js/jquery-3.2.1.slim.min.js"></script>
<script src="/assets/js/popper.min.js"></script>
<script src="/assets/js/bootstrap.min.js"></script>
<!-- For all browsers -->
<link rel="stylesheet" href="{{ '/assets/css/main.css' | absolute_url }}">
<link rel="stylesheet" href="{{ '/assets/vendor/prism/prism.css' | absolute_url }}">

<!--[if lte IE 9]>
  <style>
    /* old IE unsupported flexbox fixes */
    .greedy-nav .site-title {
      padding-right: 3em;
    }
    .greedy-nav button {
      position: absolute;
      top: 0;
      right: 0;
      height: 100%;
    }
  </style>
<![endif]-->

<meta http-equiv="cleartype" content="on">