Piwik\AssetManager\UIAssetMerger\StylesheetUIAssetMerger::rewriteCssImportPaths PHP Method

    private function rewriteCssImportPaths($content, $pathsRewriter)
    {
        $content = preg_replace_callback("/(@import \")([^\")]*)/", $pathsRewriter, $content);
        return $content;
    }