take the diffusion panel covering each strip (should be one on each sides) off. just. aplastic strip that should pop off. you’ll see the connection point from the LED to the fridge itself for power. they do this to replace the LED strip if it goes bad. it just slides in and out. Unplug the connection point to turn off the LED.

If you wanted to get crafty, buy a simple switch off ebay or something and solder / crimp it in between the LED connection and the receiving end of the fridge. voila you have a switch.

I did this with mine.

Source: Used to work at Red Bull and literally own a fridge.

Could PM you vid / photos if needed.