Sugar and Spice theme- change image padding

Hi, I love this theme and so far I’ve found it really easy to make the small modifications I want.

However, I can’t figure out how to make my signature look good, because I also have the simple share buttons plugin installed. I have just been inserting my signature manually on each post, but the padding is too large between my signature and the share buttons and it looks funny. Ideally I don’t want to change the padding on all my images, just the signature imaage.

My site is https://www.deardiy.com, and you can see what I mean on this post.

Thanks for any help anyone can give me!