Aya

This is a plasma theme that uses system colors and is intended to present a simple, clean feel. It may not be to everyone's taste, but hopefully someone finds this useful.To install: It is now included with KDE. In between major KDE point releases, updates can be installed using "New Themes" in the Desktop Settings dialog.Note: The shutdown dialog theme in the version provided here works only with KDE 4.1.4 and later.

Source: https://www.opendesktop.org/p/998876