def detect_css(str)
      str = detect_unicode_bom(str)

      if name = scan_css_charset(str)
        encoding = Encoding.find(name)
        str = str.dup
        str.force_encoding(encoding)
        len = "@charset \"#{name}\";".encode(encoding).size
        str.slice!(0, len)
        str
      end

      # Fallback to UTF-8
      if str.encoding == Encoding::BINARY
        str.force_encoding(Encoding::UTF_8)
      end

      str
    end
def detect_css(str)
      str = detect_unicode_bom(str)

      if name = scan_css_charset(str)
        encoding = Encoding.find(name)
        str = str.dup
        str.force_encoding(encoding)
        len = "@charset \"#{name}\";".encode(encoding).size
        str.slice!(0, len)
        str
      end

      # Fallback to UTF-8
      if str.encoding == Encoding::BINARY
        str.force_encoding(Encoding::UTF_8)
      end

      str
    end
Public: Detect and strip @charset from CSS style sheet.

 str - String.

 Returns a encoded String.