Additional margin spacing

I’m trying to add extra margin spacing to my interface because I don’t like how crowded it feels especially on mobile. I did try the route of custom cards with CSS but ran into issues due to me using a lot of vertical stacks.

Is there a way to add a custom style sheet that perhaps I can override in some way or is there a way just to add more spacing in general?

The goal is to have more background showing and more spacing between cards. Thanks!

Add an empty header to all your cards.

I think I did a bad job explaining. I want the background to show through more.

In this desktop screenshot, I want more margin to be added to the columns/rows. Custom card helped somewhat, but then some wonky stuff started happening with me losing my 4th column.