Can I style a tag?

In the class manager I can style headers, links and a limited part of tags.
I wonder if it is possible to style all the tags.
In fact when I build a gallery and set it Edge to edge I can style it with a class in order to have a little blank space on lateral sides.
But when I see it on a mobile the images inside each row touch each other without any space in between. And there is no way to style this via Gutters or Margin.
To style every image with a .img class it’s a very long play.
Any workaround?

But nobody calls and nobody came.