First Look at Zen/Tao

The files we've copied from Zen are instructive as they provide us with a several CSS files and a variety of approaches to overriding the default themeable functions. There are two variations on one theme here—a variable width version named "Zen" and a fixed width version named "Zen-fixed". Both use the same underlying PHPTemplate files but each has its own style.css file to control the layout. We will maintain this structure in our new theme, creating both "Tao" and "Tao-fixed.".

CSS in Zen/Tao

The CSS implementation in the Zen/Tao theme is different from what we've seen in previous themes in two aspects: First, there is the presence of the sub-theme, and second, the theme employs multiple CSS files.

The creation of a sub-theme—a theme within a theme, if you will—is made possible by the way Drupal works with themes. The system allows you to create multiple themes based on the same set of underlying files through the use of an additional CSS file placed within a...