Adding a bottom border to Ishimoto gallery

Hello! I am trying to add both a top and bottom border to my gallery. I was able to add a top, but the bottom doesn't show to show.

Here is the code I'm using:

.slide { 
  border-top: 3px solid #000000;
  border-bottom: 3px solid #000000;
}

Here is what it ends up looking like: http://screencast.com/t/f7UHuMxtHJb

It looks like there is space there that should be where the border is, but it's not showing up. Any thoughts on how to get this to show?