This is a Python script for Linux PC's to control the color temperature of the screen. It controls the color temperature of the screen according to the height of the sun in the sky.
It also turns the screen off for a configurable amount of time at configurable intervals, to give the eyes a break. Default is the 20-20-20 rule.
sudo apt-get install python3 xrandr sct
Download the script and set it as a startup application using your desktop's settings.