2Gig Panel Power Wires?

I have a 2gig panel that I want to replace with a fire tablet. I don’t understand how the panel is setup for power given the wires shown here https://imgur.com/a/YWLkBOb. In my closet there is a wall plug connected to a black/red wire and when I pull that out I see the panel falls to battery power. I’m not seeing how the black/red wire transitions into the multiple color wires to power the panel. Any ideas? Thanks.