How to change retroarch menu style

I have been seeing screenshots of people having different menu styles in retroarch other than the green default one. How do you change and/or get those?

Here you go:

  1. Main Menu in Retroarch > Settings
    cpi-ra01

  2. Select User Interface
    cpi-ra02

  3. Select Appearance
    cpi-ra03

  4. Menu Color Theme
    cpi-ra04

  5. Choose your favorite; enjoy!
    cpi-ra05