core-bundle/src/Resources/contao/library/Contao/Combiner.php
protected function handleCss($content, $arrFile)
	{
		$content = $this->fixPaths($content, $arrFile);

		// Add the media type if there is no @media command in the code
		if ($arrFile['media'] != '' && $arrFile['media'] != 'all' && strpos($content, '@media') === false)
		{
			$content = '@media ' . $arrFile['media'] . "{\n" . $content . "\n}";
		}

		return $content;
	}
protected function handleCss($content, $arrFile)
	{
		$content = $this->fixPaths($content, $arrFile);

		// Add the media type if there is no @media command in the code
		if ($arrFile['media'] != '' && $arrFile['media'] != 'all' && strpos($content, '@media') === false)
		{
			$content = '@media ' . $arrFile['media'] . "{\n" . $content . "\n}";
		}

		return $content;
	}
Handle CSS files

@param string $content The file content
@param array  $arrFile The file array

@return string The modified file content