Trying to change a font while using a theme

activating a font in default obsidian is easy enough, theres already a really good forum post about it. however, it only seems to work while using the default theme. im currently using the “Nostromo” theme, and i wanted to change the text font to “Cascadia Mono”. it doesn’t seem to be working… do i need to edit the theme itself? or is this just not possible?