class SassC::Engine

def post_process_css(css)
  css += "\n" unless css.empty?
  unless @source_map.nil? || omit_source_map_url?
    url = if source_map_embed?
            "data:application/json;base64,#{Base64.strict_encode64(@source_map)}"
          else
            URI::DEFAULT_PARSER.escape(source_map_file)
          end
    css += "\n/*# sourceMappingURL=#{url} */"
  end
  -css
end