When I had Zorin lite installed few months ago I used XSCT and I also use it on Linux Mint XFCE on my system (that is based on ubuntu noble), but now I see that the package is no more listed for ubuntu jammy Zorin 17.3 is based on.
You can use it in Zorin 18 or try if it will work by entering
sudo apt install xsct
It is a very simple terminal program but the color temperature is always reset when you reboot (or you have to add a script or commands to autostart) and is not automatically adapted to the day/night cycle.
When you want a warm temperature simply enter e.g.
xsct 3500
for a cool temperature
xsct 6500
A program that is more configurable is redshift / redshift-gtk
This can set the screen temperature depending on your geolocation, but there were problems reported with the geolocation service and it is not maintained so that it is recommended to set the geolocation manually. I haven't tried it yet (I tried but at my first days with Linux it was too difficult for me).
You can install it with
sudo apt install redshift redshift-gtk
It is also a terminal program so you can't start it via a GUI. To make the settings you would have to use the terminal or edit a .config file.
Unfortunately there is no nightlight function as in gnome.