This is not a stand alone app. Theme requires Kustom Live Wallpaper Maker PRO application (not free version of this app).

This theme has light and dark modes (switch is on the main screen).
Prostolight KLWP theme supports all screen ratios.

What you need:
✔ Kustom (KLWP) PRO
✔ Compatible launcher that supported by KLWP (Nova launcher is recommended)

How to install:

✔ Download Prostolight KLWP theme and KLWP PRO application
✔ Open your KLWP app, choose menu icon on top left, then load preset
✔ Find and tap on the Prostolight KLWP theme
✔ Hit "SAVE" button on the top right

Instructions:

In the Nova launcher settings you need:
✔ select 1 screen
✔ hide status bar and dock

In the KLWP settings you need:
✔ select 1 screen

Please contact me (hewood00@gmail.com) with any questions/issues before leaving a negative rating about Prostolight KLWP theme.