bookdown::gitbook:
  config:
    toc:
      collapse: section
      before: |
        <li><strong><a href="./">R for Data Science</a></strong></li>
    edit:
      link: https://github.com/hadley/r4ds/edit/master/%s
      text: "Edit"
    sharing: no
  css: r4ds.css

bookdown::pdf_book:
  latex_engine: "xelatex"