I am immensely grateful with you! I swear I made my research in the forum and I found many topics that talked about this, but none of them were conclusive (the ones I saw). I found one that I think was the one I needed but it was in french, I translated with google translator, but I wasn't much of a help.
I found difficult to find the main theme.xml (even with WinSCP) but I did it.
I am truly grateful, thanks! You all make a great job!