Q about GB global styles

I made a couple of global styles for images to be floated to the right or to the left. I basically wanted them to have a consistent margin so there's space between the images and the text that goes around them.

The margins appear in the editor, and the image floats left or right depending on which preset I choose, but on the published page it just looks like an image with default block styling - which is to say it's aligned left and has no padding or margins whatsoever.

Do I need to put the image in a container in the preset?