Single huge .css file vs. multiple smaller specific .css files?

Question

Is there any advantage to having a single monster .css file that contains style elements that will be used on almost every page?

I'm thinking that for ease of management, I'd like to pull out different types of CSS into a few files, and include every file in my main <link /> is that bad?

I'm thinking this is better

1. positions.css
2. buttons.css
3. tables.css
4. copy.css

vs.

1. site.css

Have you seen any gotchas with doing it one way vs. the other?

Answer 1

This is a hard one to answer. Both options have their pros and cons in my opinion.

I personally don't love reading through a single HUGE CSS file, and maintaining it is very difficult. On the other hand, splitting it out causes extra http requests which could potentially slow things down.

My opinion would be one of two things.

1) If you know that your CSS will NEVER change once you've built it, I'd build multiple CSS files in the development stage (for readability), and then manually combine them before going live (to reduce http requests)

2) If you know that you're going to change your CSS once in a while, and need to keep it readable, I would build separate files and use code (providing you're using some sort of programming language) to combine them at runtime build time (runtime minification/combination is a resource pig).

With either option I would highly recommend caching on the client side in order to further reduce http requests.

EDIT:
I found this blog that shows how to combine CSS at runtime using nothing but code. Worth taking a look at (though I haven't tested it myself yet).

EDIT 2:
I've settled on using separate files in my design time, and a build process to minify and combine. This way I can have separate (manageable) css while I develop and a proper monolithic minified file at runtime. And I still have my static files and less system overhead because I'm not doing compression/minification at runtime.

note: for you shoppers out there, I highly suggest using bundler as part of your build process. Whether you're building from within your IDE, or from a build script, bundler can be executed on Windows via the included exe or can be run on any machine that is already running node.js.