function setCssCompressor($compressor)
    {
        if (!isset($this->compressors[$compressor])) {
            throw new \InvalidArgumentException(sprintf('Undefined compressor "%s"', $compressor));
        }

        $css = $this->contentType('.css');

        if ($this->cssCompressor !== null) {
            $this->bundleProcessors->unregister($css, $this->compressors[$this->cssCompressor]);
        }

        $this->cssCompressor = $compressor;
        $this->bundleProcessors->register($css, $this->compressors[$compressor]);
    }