Polygons social media bar is not aligned? the facebook one.

i'm not really sure if its meant to be the way it is, or maybe it's just me, but the facebook hover, over the social media bar is not aligned.

here's what i'm talking about.

as you can see, the bottom half of the hover is not aligned.

shouldn't it look like the rest of the bars, there aligned just fine. i thought it would look something like this.

IDK, maybe its just my computer, could anyone tell me if they have the same problem?