class SassC::Engine

def post_process_css(css)
  css += "\n" unless css.empty?
  unless @source_map.nil? || omit_source_map_url?
    url = URL.parse(output_url || file_url)
    source_mapping_url = if source_map_embed?
                           "data:application/json;base64,#{Base64.strict_encode64(@source_map)}"
                         else
                           URL.parse(source_map_file_url).route_from(url).to_s
                         end
    css += "\n/*# sourceMappingURL=#{source_mapping_url} */"
  end
  css
end