Ok, this is pretty embarrassing. I just got the game and I can't figure out how to quit! Ctrl-Alt-Delete didn't even work, let alone alt-tab. I had to hit the power button on my computer. How do I get out of the game?!?

If you're in the game itself, hit ESC to bring up the pause menu. There's options to return to the main menu or quit the game entirely.

If you're on the main menu, a little (X) should appear in the upper right corner above the title. Click that to exit.