The colors on this page are changing often, both because I'm reading Cailin Boyle's Color Harmony for the Web and because I'm working to find better ways to make flexible sites with Ceres.
In this version, I've added attributes to my Ceres File for things like BackgroundColor and BorderColor. The default values for these colors define the overall design. If a page wants a different color scheme, of course, it's easy to set different colors. Better yet, if you want an entire section to share a different color scheme, you can simply create a prototype for the pages in that section.
But there are many other ways to do this in Ceres! Perhaps you'd rather set the colors in style sheets: go ahead! Instead of defining a bunch of color attributes, we define a string sttribute containing the name of the style sheet. The default value is the site's default stylesheet, but we can easily set a different style for a single note or an entire selection. Or, we might define an attrbute called BodyTag, containing the entire Body tag in one chunk.
The point is not that Ceres makes it easy to play with colors, but rather that Ceres makes it easy to adapt your entire site -- manually, with power tools, or automatically with agents.
Ceres is simple, but it's also deep: you can get started quickly, but there are lots of ways to do things.