@media all and (min-width:500px) {
    @document url(http://www.w3.org/),
                   url-prefix(http://www.w3.org/Style/),
                   domain(mozilla.org),
                   regexp("https:.*")
    {
      /* CSS rules here apply to:
         + The page "http://www.w3.org/".
         + Any page whose URL begins with "http://www.w3.org/Style/"
         + Any page whose URL's host is "mozilla.org" or ends with
           ".mozilla.org"
         + Any page whose URL starts with "https:" */

      /* make the above-mentioned pages really ugly */
      body { color: purple; background: yellow; }
    }
}