  {%- if site.enable_math -%}
  <script type="text/javascript">
    window.MathJax = {
      tex: {
        tags: 'ams'
      }
    };
  </script>
  <script defer type="text/javascript" id="MathJax-script" src="https://cdn.jsdelivr.net/npm/mathjax@{{ site.mathjax.version }}/es5/tex-mml-chtml.js"></script>
  <script defer src="https://polyfill.io/v3/polyfill.min.js?features=es6"></script>
  {%- endif %}
