def custom_404_body
      filename = File.join(root, "404.html")

      File.exist?(filename) ? File.binread(filename) : nil
    end
def custom_404_body
      filename = File.join(root, "404.html")

      File.exist?(filename) ? File.binread(filename) : nil
    end
Returns the body of the custom 404 page or +nil+ if none exists.