How to add the use of additional.css in a mod?

[Taurus1]

Can someone please help me on how to add the use of the additional.css to a mod. I am using a vb3 mod that was converted to work in vb4. It works in most cases, but because it does not use the additional.css it breaks in some templates.

Would it be possible to add the use of the additional.css to a mod? And if possible, how would I do it?

Thank you so much!