Same Banner image shows up differently size wise on the mobile to the desktop.

[sandymay]

I've added a Banner image to my website and it shows up differently size wise on the mobile to the desktop.  I make it smaller by way of the XS to Large buttons to fit on the desktop and then it doesn't look any good on the mobile view and vise a versa meaning it crops it and most is gone.  I'm on the free plan and my business currently wouldn't warrant a paid plan atm as it's a new venture.  Can this be fixed somehow ?  Thank you.