This theme is exactly the one that Google put in Android M second preview and N, extended on more apps. Now with optional Google Pixel colors!
The theme installs through Substratum Theme Engine app, that you can download here, IT REQUIRES ROOT, Busybox, and a Layers or Substratum compatible ROM: https://goo.gl/BB5eio
Theme Ready Google Apps supported but not required, install this app* https://goo.gl/nH1xlo , download the package for your system, and install it from your recovery. *If you don't want the app, you can directly download the flashable zip here. https://goo.gl/r1BnxK
This is the icon pack that you can see in the first screenshot, that I personally made to fit dark themes properly: https://play.google.com/store/apps/details?id=com.piereligio.darkpixelip
For any problem or suggestion, send me e-mail at [email protected] or join my G+ comminity https://goo.gl/mqrm9u or join my Telegram chat group https://goo.gl/gbNhZc
The theme has been tested on many ROMs, including stock and custom Marshmallow and Nougat ROMs. Android 7.1, 7.1.1 and 7.1.2 beta are supported. On 7.1.x Substratum Legacy ROMs (including stock ones) you need to use an option called Frameworkless7.1RROcompatibility, and it has white notifications. Sadly it isn't possible to make them dark on that option.
-Pixel boot animation; -Pixel and Nexus ringtones and UI sounds; -4 wallpapers;
-Android N-ify XPosed module; -AOSP Contacts; -AOSP Dialer; -AOSP Launcher; -AOSP Messages; -Calculator; -Car Throttle dark mode; -Documents/Download UI; -DU Updater; -ES File Explorer; -Framework-Res; -Google Assistant; -Google Calendar; -Google Chrome; -Google Contacts; -Google Dialer; -Google Drive; -Google Keep; -Google Hangouts; -Google Inbox; -Google Keyboard (only for Google Pixel colors); -Google Launcher/Now; -Google Mail; -Google Messenger; -Google Play Music; -Google Play Store; -Google Plus; -Google Translate; -Instagram; -Kernel Adiutor's dark mode; -Nova Launcher's searchbar; -N style notifications; -Package Installer; -Pixel Launcher; -Root Explorer dark theme; -Settings; -Solid Explorer dark theme; -Substratum app; -SuperSU; -SystemUI; -Telegram (half themed only. To have it full themed, use Plus Messenger client, and use this theme: goo.gl/VPvSVO ); -Twitter night mode; -WhatsApp; -Youtube.