Update causing issues

I’m attempting to fix a client’s WordPress site in which I did not originally code. Initially the client wanted to make it so one of the category pages would make use of the plug-in to put ads on it. (all the other category pages do this and work fine). I added some code to the functions php and made a side bar php, following the standard instructions from the WordPress Codex.

But, since updating, now every image has a border and background. Where instead I want images to not have anything. Secondarily I would like the widget to be usable on the category page (news industry).

The page i’m discussing is located here: http://www.tabletopjournal.com

I can post any code if you would like to peruse, or is my best best reverting to an older back up of the site where I at least had the same layout.

Thanks in advance.

https://wordpress.org/plugins/simple-image-widget/