Possible background image in menu navigation section?

Just curious if this is possible or not? I have an image that I would like to use as the background for the menu section. You can view the image here: http://dedespawsandtails.com/wp-content/uploads/2015/04/bonenav.png

Here is an example of what I’m trying to accomplish. This screenshot has a blue background, please ignore that. http://dedespawsandtails.com/wp-content/uploads/2015/04/bonenavexample.png

I tried working some CSS magic to do this. It actually works, but does not look right.

Here is a screenshot of what I get: http://dedespawsandtails.com/wp-content/uploads/2015/04/bonenavresult.png

Here is the CSS I was trying to use:

background-image: url("http://derekdev.dev/wp-content/uploads/2015/04/bonenav.png");
background-repeat: no-repeat;