Compile the document into a CSS string and save to the specified location, or return as a string.
$doc = new \hexydec\css\cssdoc();
if ($doc->load($css)) {
$doc->save($file, $options);
}The location to save the CSS, or null to return the CSS as a string.
See the compile method.
Returns the CSS document as a string if $file is null, or true if the file was successfully saved to the specified file. On error the method will return false.