OpenVBX is a great open source web application that provides an easy to use interface to manage multiple user's phone numbers, voice mail, and phone trees. The app itself works fine out of the box but the UI is very dated and needs an overhaul. Luckily OpenVBX is extendable and allows you to create your own themes and easily add them to the app.
I struggled to find many good themes though, so I made my own! I started with Google's Material Design principals and borrowed from some of their great color schemes. The result is the same app, with the same functionality, but with a modern gmail inspired hybrid-flat design.
This theme can also be easily modified further. The code is GNU-GPL open source licensed, so you can use it as a base for your own new theme! With a couple quick tweaks in one place, you can change the colors throughout the entire app. You can also add your own font-based icons or choose different FontAesome icons as you see fit.
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