When it comes to web-design, I am horrible at producing anything remotely good looking. Thankfully there are a lot of free sources for design templates. However, a problem with these designs is that they just cover a single page, and not many use cases. If you take a look at CSS Zen Gardens, they have 1 single HTML file, and can radically style it differently by just changing the CSS file.
Now I am wondering if there is a standard HTML layout (tags and ids), that covers alot of use cases, and can be generically themed with different CSS files like Zen Garden. What I am imagining is a set of rules off how you write your html, and what boxes, lists, menus and styles you are supposed to use. A set of standard test pages covering the various uses can be created, and a new CSS file while have to support all the different pages in a nice view.
Is there any projects that covers anything similar to what I am describing?