The G213 gaming keyboard has keys that let you toggle between Windows and Game Mode, and enable and disable the keyboard's backlighting.

Game Mode
To enable Game Mode, press the Game Mode key. The Game Mode LED indicator lights up when the keyboard is in Game Mode. 

NOTE: The Windows key is disabled when the G213 is in Game Mode.

Backlighting
To enable or disable backlighting on your keyboard, press the Backlight toggle key, located above the PAUSE key in the upper right of the keyboard. The LED lights up when backlighting is enabled.