Yes, Styles are the color of your screen! Very pretty, and lots of fun! To change yours, look at the bottom of your screen on the far left. You will see a drop down box. Click on the little arrow, then select your favorite style. I, for instance, use Pinky Paws!
I tend to faver ocean mews, like the others the colors are too bright and with the background of those being white it hurts my eyes. The ocean mews has a blue background and it is easier on my eyes. I also think it would be cool to have a pastel kind of choice.
If you go into the control panel, I think it is under options, there are different styles that you can view the site in - colors, etc. I am using the oen with all blues right now!