Custom Team Colours in TFT

Hey, a couple people were telling me you could make custom team colours with the TFT WE, is this true? If so, does anyone know how to do it?

I dont know about custom team colors but i do know about custom hero glows

ya... that's a trigger... can you tell me how to do that anyways? It's not what I wanted but as you can tell from my signature I'm making a hero arena so that would be useful.