html_document:
  self_contained: true
  number_sections: no
  theme: flatly
  highlight: tango
  mathjax: null
  toc: true
  toc_float: true
  toc_depth: 3
  df_print: paged
  css: include/site.css
  includes:
    in_header: include/header.html
    after_body: include/after_body.html