@cmolchany You could just add a basic <div> around your adsense code (if possible) so then you an also add a class to it which you can then style from your css. Although, since adsense code usually has a set defined width, it may or may not resize….which is a problem if the space you have it in is too small and not wide enough to properly display the entire ad.
I haven’t used adsense in a long time so I’m not sure if Google gives the option to adjust the size to what you want, or if they allow the ads to resize according to the size of the space it’s located in.