No, for the moment only plain CSS is supported.
More in Insert Code FAQs
- Does Custom Code Inserter SGTLab work with my theme?
- How will Custom Code Inserter SGTLab affect my page speed?
- Why add custom CSS in your store?
- Does the app modify the code I write in the editor?
- What if I change the theme?
- What if I want to add multiple external CSS codes?
- What will happen after I uninstall the app?
- I've added the code but there are no changes on my website. What should I do?