I've downloaded and installed the hummingbird plugin. After I turned on browser caching, it changed the appearance of our home page. It turned all of the black container boxes on our homepage from black to white. Fortunately, we ran a few tests, and it looks like it affects the appearance of the site if you're logged into the dashboard. As long as we're the only ones who see it, it isn't a big deal, but do you have any idea why it would do it?
I can get you a couple of screen shots if it would help to have a visual.