_layouts/default.html

<!DOCTYPE html>

<html>
    <head>
        <meta charset="utf-8"/>
        <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
        <script>

            /* https://code.jquery.com/jquery-3.2.1.min.js */
            {% include jquery-3.2.1.min.js %}

        </script>
        <script>

            /* https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js */
            {% include bootstrap.min.js %}

        </script>
        <script type="text/x-mathjax-config">
            MathJax.Hub.Config({
                tex2jax: {
                    displayMath: [["\\[", "\\]"]],
                    ignoreClass: "nostem|nostem|nolatexmath",
                    inlineMath: [["\\(", "\\)"]]
                },
                asciimath2jax: {
                    delimiters: [["\\$", "\\$"]],
                    ignoreClass: "nostem|nostem|noasciimath",
                    processEnvironments: true
                }
            });
        </script>
        <script>

            /* https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-MML-AM_CHTML */
            {% include MathJax.js %}

        </script>
        <script>

            $(function() {

                // responsive embed
                // http://getbootstrap.com/components/#responsive-embed
                $('div.videoblock div.content').addClass('embed-responsive embed-responsive-16by9');
                $('div.videoblock div.content iframe').addClass('embed-responsive-item');

            });

        </script>
        <style>

            /* https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css */
            {% include bootstrap.min.css %}

        </style>
        <style>

            /* asciidoctor -a linkcss -b html5 -D . /dev/null */
            /* remove a:focus for accessibility */
            {% capture css %}{% include asciidoctor.css %}{% endcapture %}
            {% capture none %}{% raw %}a:focus { outline: none; }{% endraw %}{% endcapture %}
            {% capture dotted %}{% raw %}a:focus { outline: thin dotted; }{% endraw %}{% endcapture %}
            {{ css | replace: none, '' | replace: dotted, '' }}

        </style>
        <style>

            /* https://github.com/asciidoctor/jekyll-asciidoc#adding-supplemental-assets */
            {% include asciidoc-pygments.css %}

        </style>
        <style>

            /* http://stackoverflow.com/a/30195325 */
            ol > li:before {
                content: "";
                display: block;
                height: 1em;
            }
            ol > li > p:first-child {
                margin-top: -1em;
            }

            /* wrap inline code */
            *:not(pre) > code {
                white-space: pre-wrap;
            }
            
            /* don't wrap code blocks */
            pre, pre code {
                overflow: auto;
                white-space: pre;
                word-wrap: normal;
            }

            /* match margin-bottom of div.paragraph */
            div.stemblock div.content {
                margin-bottom: 1.25em;
            }

            /* fill page */
            table {
                width: 100%;
            }

            /* allow captions to wrap */
            .tableblock > caption {
                max-width: inherit;
                white-space: inherit;
            }

        </style>
        <title>{{ page.title }}</title>
    </head>
    {% if page.toc != false %}
        <body class="toc2 toc-left">
            <div id="header">
                <div class="toc2" id="toc">
                    <div id="toctitle">Table of Contents</div>
                    {{ page.document | tocify_asciidoc: page.toclevels }}
                </div>
            </div>
            <div id="content">
                {{ content }}
            </div>
        </body>
    {% else %}
        <body>
            <div id="content">
                {{ content }}
            </div>
        </body>
    {% endif %}
</html>