So I tried doing that, however, whenever I would try to preview the CSS it wouldn’t force the color changes, just the CSS changes. Anyway to preview off a color change? Or a simpler way to do it in CSS as there isn’t a preview generated based off color changes that I can find.
Where I can preview off one of these to generate the preview links:

Or does it have to be the CSS/HTML only?
For example, I’m trying to offer a dark theme similar to this one but the colors don’t override the default theme when I use the CSS changes only.