Black Screen Champion Select

In both ARAM and and ranked 3v3, I've gotten into a game only for my client to turn all black minus the chat bar at the bottom. The first time this happened which was in ranked 3v3s, my friends were talking about champ select which was apparently going on normally. My client remained black and didn't let me do anything, eventually causing me to forcefully dodge. The same thing happened again in the ARAM queue a few days later (today). I was watching a YouTube video at least the second time, in case that helps.