Originally Posted by rogue_ronin
Creating macros to write CSS for any reader should be dead-simple,
You don't need macros for that - as long as your (X)HTML files are created with styling in mind, the CSS will be a sompletely standalone part of your book - likely you will have most CSS for all books in one file, with perhaps an additional "supporting" CSS file for particular books. The whole point of CSS is, if you want to change the appearance of a HTML, you make your changes only
in the separate CSS file, nowhere else.
As for organizing everything neatly, you may want to look at my "Calibre preprocessor" H2LRF