Is there any tutorial about this newly added feature?
My main problem with it is it's very hard to adjust CSS with it.
Is there any overriding mechanic which enables me to do CSS adjusting in a non-compiled CSS file?
Just need explanation.
We recommend that you create custom CSS files and simply override the original CSS for any content elements you desire.
Please see these links to better understand how to create your own custom CSS file for our newer LESS templates:
LESS CSS
Your first CSS-Less custom file or CSS custom file