Yisrael,
Thanks for the reply. Maybe my original post was not clear. I am aware of the theme customizations that can be made and saved in the Wix Editor, however, I was hoping to find a way using Wix Code to make more advanced style changes. The Wix Editor is extremely limited.
In my example from the original post, I want to use “Proxima Nova Extra Bold” and “Proxima Nova Medium”. To accomplish Proxima Nova Extra Bold all you need to do is style Proxima Nova with
font-style: normal; font-weight: 800;
According to wix code documentation, you can assign these styles “inline” for each text element. But hoping to find a way to do this site wide, ideally updating the theme tags.