Cards Evolution

Hi,i just start playing ep3 recently and saw this article:

http://www.pso-world.com/sections.ph...cle&artid=1866

So my question is, where can i transform cards?i cant find the way to do it.(i only play offline)

It happens randomly when you select your reward cards at the end of fights. All cards have a % chance of evolving into a better card.

ooohhh ok,thanks for your fast answer :) .
So far i'm Clvl7 and it never happened to me.