Hi guys,
I've been searching around bur didn't found any similar problem... I'm facing some issue that was disturbing me, I've tried to reset the kde settings but wasn't working...
I was also trying to download a new theme for simple locker but wasn't working at all...

The problem is, on the fields there's a grey box that is supposed to be black, and it is nearly difficult to read the username and password labels and also it's ugly...
the problem started a few time ago when I've installed something thru apt-get and it messed with plasma desktop, I could restore many of the desktop settings and now all is good except by this lock screen...

do anyone have an idea on what could be happening and how to solve it?

I know there are some files to configure this window on:
/usr/share/kde4/apps/ksmserver/screenlocker/org.kde.passworddialog/contents/ui

but not sure if I need to change something there or not...

there's a screen shot;
http://s13.postimg.org/l1cecaa1j/snapshot_lock.png

thanks in advance!