message: Use light/dark themes
diff: @@ -5,7 +5,7 @@ src = "docs"
  language = "en"
  [output.html]
  -default-theme = "ayu"
  +preferred-dark-theme = "ayu"
  curly-quotes = true
  git-repository-url = "https://github.com/sampsyo/bril"
  site-url = "https://capra.cs.cornell.edu/bril/"
  