NulledBB User Panel Background

I hope I'm not in the wrong category, if I am I'm sorry. First of all, hats off to the whole NulledBB team, the forum looks just awesome. What I especially liked are these animated profile backgrounds. As far as I've noticed, the whole thing runs on myBB. Is this an addon, these backgrounds or have you coded this yourself?

Since you have posted this here on MYBB there is a profile background for MYBB forums. As for NulledBB the one (used) here is a custom modification.