Using TiddlyWiki palettes is not straightforward! You may use colour macro, but some colors are created using colour macro tehmselves, … If you develop some colorful elements, when working with dark, light themes it is difficult to get the right color for your element.
BenWebber has created a nice plugin to create css variables from TiddlyWiki palettes. This makes using colors much simpler.
https://benwebber.github.io/tiddlywiki-plugins/#css-palette
For the active palette you may directly use the color like:
@@color: var(--tc-alert-highlight);
Lorem ipsum dolor sit amet.
@@