I'm having a problem with finding where I can change my project's theme.
For now, I'm learning android using [this tutorial](http://developer.android.com/training/basics/firstapp/building-ui.html).

My project's theme looks like this:
![enter image description here](https://i.stack.imgur.com/33LaV.png)

And I'd like this UI looked like that:

![enter image description here](https://i.stack.imgur.com/fg2VV.png)

Where can I find that theme and instructions, to install it?
Thanks.