Line in Row Background

In Firefox a white line appears randomly on the background of the row when I use the “big triangle” edge. A 1px color line is also appearing at the bottom of the background on some pages as well. It doesn’t appear to be happening in Chrome or Safari. I’ve got the latest Firefox installed. Is this a bug or can it be resolved? This is important because that edge is an important design feature of my site.

Here’s a sample

http://52.89.101.172/our-locations/