excerpts on mobile

Hi, I am completely new to both wordpress and webdesign in general, so apologies if I’ve missed something obvious. I’m trying to set up the recent posts widget to display excerpts on desktop, but not on mobile. Is there a feature to achieve this, and if not, is it easy enough to code for a novice?
Thanks in advance!

P. S. the plugin is precisely what I needed and very intuitive. A big thank you to the creators!