I installed kubuntu-desktop
and every thing was fine. Then later when I actually logged in to Kde, I decided that I still like Unity better so I ran sudo apt-get purge kubuntu-desktop && sudo apt-get autoremove
. After that bits and pieces of my Ubuntu/Unity have been Kde styled. All browsers have Kde icons and some applications show 'About Kde' in their menus, all text fields have that 'bluesh glow' around them, etc.
What is still left of Kubuntu?
Note: I saw this question and this question, but both where outdated and didn't work.
Best Answer
Remove from your $HOME directory any file that is of the form
.gtkrc
After removing such files, go back into your Appearance settings and change your theme to Ambiance or Radiance, apply, then move onto your preferred theme.