DIAGNOSIS The router's default setting has the ROG-themed RGB lighting effects enabled. You want to disable it entirely, which is a simple setting change.
FIX Log into the router's web interface. On the left-hand menu, go to Administration, then select the Operation Mode tab. Near the bottom of that page, you'll see a setting called "ROG Lighting." Click the toggle switch to turn it OFF. Click "Apply" at the bottom of the page. The front LED strip should go dark immediately.
IF THAT DIDN'T WORK If the toggle doesn't respond or the lights come back after a reboot, you might have a minor firmware glitch. Try a soft reboot by unplugging the router's power for 30 seconds and plugging it back in. Then check the setting again.
HEADS UP Turning off the ROG lighting here turns off the entire decorative strip. The individual status LEDs for power, internet, and Wi-Fi will remain on unless you also disable them using the physical "LED ON/OFF" button on the back of the router.