All Beacon templates have a range 'template colors' associated with them. If you change one of the template colors, that color will be updated wherever it was used throughout the document.
This is useful if you need to quickly change the colors used throughout a document.
You can access the Template Colors for a document by clicking the 'Default Styles' link in the Document Settings area:
In this example, Template Color 3 is set to yellow:
If we change that color to pink, every item that used Template Color 3 in this document will also be updated. You can see that here on the cover page:
And on the Table of Contents: