Green zoom button?

I am trying Scrivener for the first time and have come to a problem in the tutorial. I encountered this sentence:

You may find this text a little scrunched up now. If so, click on the green “zoomâ€

The green zoom button is a feature of all OS X windows. You can find it in the top left-hand corner of the window, one of the three “traffic light buttons”. They may all be grey if you have the Graphite Theme set, though.

That did the trick! I did have the graphite display mode, and now that it is the blue mode, I have traffic lights. Thanks much!