How do you control the backlighting?

you use fn or alt at the same time with your 6 keys where pgup and pg down are

Questions & Answers: CORN White Gaming Mechanical Gaming Keyboard RGB Backlit LED with Wrist Rest, Blue Switches - Clicky, Metal Panel 104 Keys for Mac, PC, White

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CORN White Gaming Mechanical Gaming Keyboard RGB Backlit LED with Wrist Rest, Blue Switches - Clicky, Metal Panel 104 Keys for Mac, PC, White

Anti-ghosting 104 Keys: N-key rollover Allowing multi-keys to work simultaneously with high speed. Each key is controlled by independent switch, let you enjoy high-grade games with fast response
DIY Blue Switches: Custom mechanical switches designed for longevity, responsiveness, and durability. Mechanical keys with medium resistance, audible click sound, and tactile feedback. 50 million times keystroke test. Include 5 spare switches for replacement. Blue switch is clicky and audible
Programable full RGB backlighting: You can program all of the keys to be the same color/what color you want with no driver needed.13 RGB Backlighting mode with Fn+Ins. There is a solid color backlit mode. Double-shot keycaps for crystal clear backlighting and extreme durability
Key Shortcuts and Ergonomic design: Easy to access to calculator, email, web browser, volume, media etc with FN+F1-F12.