A lot of questions regarding Gradients, z-level, and fonts

[FlyingSaturn]

So apparently, I'm making a desklet where there will be quite a lot of attention towards intuitive ricing.

Now, I have a few questions:

• Gradients

  • In the Night Light settings, how did you guys make that gradient?

  • Can we change the colour gradients on the go? For example, suppose I make an HSL colour slider, somehow. Now, if I change the saturation, the hue slider's colours will go towards a shade of grey. Assuming that I am somehow able to program that change, can Cinnamon gradients' colours be changed on-the-fly?

• z-stack

This idea came to me after I thought that the percentage I will show can be expressed like this (assume that the black box is a square):

instead of this (this will also be supported)

Basically, the background for a lot of desklets is transparent. I was thinking of somehow making the z-stack layers (background and text) swap.
But... a lot of desktop themes aren't even compatible with that. They make the transparent space as black. Like, how will we ensure that there's a literal stencil-like hole on the desklet? Is that even possible?

• Fonts

We had a lot of apps where we could select the font. We even have the Font Selection menu where we have changed the whole font of the system. My question is, can it be done for the fonts of applets and desklets? Could you guys please guide me to the portion of the St docs where text can be shown or pie charts can be made, like the literal content (which is not the title)?