title: How to add multiple CSS files to a revealjs presentation in R Markdown?
body: <p>I am trying to put together a reveal.js presentation in RStudio using R Markdown. I want to include multiple CSS files: </p>
  
  <pre><code>---
  title: "Slick Presentation"
  output: 
    revealjs::revealjs_presentation: 
      css: "css/style.css","fonts/fonts.css"
  ---
  </code></pre>
  
  <p>I have tried a comma separated list of values, but the YAML parser does not appear to like this.</p>