[HELP] Change some colors

I want to change Settings.apk Background color like this (i just want to make a dark theme):

I saw many tutorials here, but nothing found about my files. :confused:
If anyone can help me here are the files framework-res, Settings and SystemUI: https://mega.nz/#!C94CyJLK!soKx4RArb...e2fsOGHUtWQ_x4
You just need to tell me what file to edit, i want to edit it myself to learn.
Thanks anyone who help me. :D