How to change the default color palette?

Hi there!

Is there any possibility to change the default palette.

For example all pages and blocks in them have a default palette of "BRIGHT 2"

I would like to have "LIGTHEST 1" as the default palette.

Is it possible?
The help center gives this information but I can't figure it out.
Thanks!!!

Very sadly this isn't generally changable any more. You used to be able to do it on desktop. Then that option went away, but it remained on the mobile app. Now there is still a tab for "site theme" in the mobile app, but no longer has the option to change the default theme. This is one of the few things that is set when you pick a template, and I have no idea why you can't change it. I've Support asked on a few occasions but never got a satisfactory response. 

If you have the time you can go through and change all of the colours in the default theme to what you want, but that's rather tiresome if you are switching from a light to a dark theme.