I used this tutorial to facelift my Holo app for Lollipop: http://android-developers.blogspot.ru/2014/10/appcompat-v21-material-design-for-pre.html
What I have:
This might also be helpful in addition to @Andrey Shcherbakov's answer if you want to have more control of each individual color.
#FFFF00 #444400 #00CC00