You can use this app to set the color of status bar through Accessibility Service :

Color Status Bar

(Note: This app runs in background to enable the color.

And, this app will work only on devices running Android 5 or above..)

But to change the color of navigation bar, you need root access.

If your device is rooted, do the following to change navbar color:

1. Install Xposed Framework and Xposed Installer app.


2. Install "GravityBox" module (varies for different Android versions) and reboot.


3. Open GravityBox app, goto Navigation Bar Tweaks


4. Under Colors section, Enable Navbar Colors and set your desired color.