def consume_escaped
      return "\ufffd" if @s.eos?

      if hex_str = @s.scan(RE_HEX)
        @s.consume if @s.peek =~ RE_WHITESPACE

        codepoint = hex_str.hex

        if codepoint == 0 ||
            codepoint.between?(0xD800, 0xDFFF) ||
            codepoint > 0x10FFFF

          return "\ufffd"
        else
          return codepoint.chr(Encoding::UTF_8)
        end
      end

      @s.consume
    end
def consume_escaped
      return "\ufffd" if @s.eos?

      if hex_str = @s.scan(RE_HEX)
        @s.consume if @s.peek =~ RE_WHITESPACE

        codepoint = hex_str.hex

        if codepoint == 0 ||
            codepoint.between?(0xD800, 0xDFFF) ||
            codepoint > 0x10FFFF

          return "\ufffd"
        else
          return codepoint.chr(Encoding::UTF_8)
        end
      end

      @s.consume
    end
Consumes an escaped code point and returns its unescaped value.

 This method assumes that the `\` has already been consumed, and that the
 next character in the input has already been verified not to be a newline
 or EOF.

 4.3.8. http://dev.w3.org/csswg/css-syntax/#consume-an-escaped-code-point