I’ve noticed 4 css files next to each other taking around 0.5 - 1 second to load. I was about to amalgamate them into 1 file when I noticed they were running in parallel. If I did amalgamate them then it would actually take longer.
So perhaps its best not to put all css in one file but to split them into many files? Can someone confirm this?
It’s better to make them 1 file because you will be saving 3 http request, and therefore letting other element load.
I recommend you use an app like Minify app that will combine, minify, cache, and gzip your css file.
If you like something more robust that will call the css file when needed, i would recommend YUI loader. You can define your modules, and on which page to use those module. It will call the CSS file in one http request.