Featured Content boxes around each article (page)

I would like to put a box around each page I have added to the Featured Content section of the Theme. Or at least a vertical line between each of the 4 columns, in my case, to help separate them. Can the line after the Featured Content section be made darker? I am using the free version of the Catch Responsive theme. Website is here (https://rarclubackup.website) and as you can tell it is a work in progress.