Reformating Gallery Slideshow on Mobile vs Desktop

Hi! Can someone help me reformat my slideshow gallery to be smaller on my mobile than on my desktop? On my desktop, it looks best as a large(L) section and on the mobile it looks better much smaller(S). When I try to edit the mobile app to small, it also changes the desktop view.  Can someone me change only my mobile view to small? 

Do you have a link?

yes its https://www.juliastephensonn.com/

@juliastephensonn Check out this video from Inside the Square. Becca walks through how to make these adjustments. 

Here's the code for gallery type you're looking to target:

@media only screen and (max-widthL 767 px) {
.gallery-fullscreen-slideshow-item {
height: 30vh!important
}}

Go to Website > Website Tools > Custom CSS and copy / paste it in the box. If it doesn't work, let us know!