How should I organize the contents of my CSS file(s)?

Have a look at these three slideshare presentations to start:

  • Beautiful Maintainable CSS
  • Maintainable CSS
  • Efficient, maintainable, modular CSS

Firstly, and most importantly, document your CSS. Whatever method you use to organize your CSS, be consistent and document it. Describe at the top of each file what is in that file, perhaps providing a table of contents, perhaps referencing easy to search for unique tags so you jump to those sections easily in your editor.

If you want to split up your CSS into multiple files, by all means do so. Oli already mentioned that the extra HTTP requests can be expensive, but you can have the best of both worlds. Use a build script of some sort to publish your well-documented, modular CSS to a compressed, single CSS file. The YUI Compressor can help with the compression.

In contrast with what others have said so far, I prefer to write each property on a separate line, and use indentation to group related rules. E.g. following Oli's example:

#content {
    /* css */
}
    #content div {
        /* css */
    }
    #content span {
        /* css */
    }
    #content etc {
        /* css */
    }

#header {
    /* css */
}
    #header etc {
        /* css */
    }

That makes it easy to follow the file structure, especially with enough whitespace and clearly marked comments between groups, (though not as easy to skim through quickly) and easy to edit (since you don't have to wade through single long lines of CSS for each rule).

Understand and use the cascade and specificity (so sorting your selectors alphabetically is right out).

Whether I split up my CSS into multiple files, and in what files depends on the size and complexity of the site and the CSS. I always at least have a reset.css. That tends to be accompanied by layout.css for general page layout, nav.css if the site navigation menus get a little complicated and forms.css if I've got plenty of CSS to style my forms. Other than that I'm still figuring it out myself too. I might have colors.css and type.css/fonts.css to split off the colors/graphics and typography, base.css to provide a complete base style for all HTML tags...


I tend to orgainize my css like this:

  1. reset.css
  2. base.css: I set the layout for the main sections of the page
    1. general styles
    2. Header
    3. Nav
    4. content
    5. footer
  3. additional-[page name].css: classes that are used only in one page

However you find it easiest to read!

Seriously, you'll get a billion and five suggestions but you're only going to like a couple of methods.

Some things I shall say though:

  • Breaking a CSS file into chunks does help you organise it in your head, but it means more requests from browsers, which ultimately leads to a slower running server (more requests) and it takes browsers longer to display pages. Keep that in mind.
  • Breaking up a file just because it's an arbitrary number of lines is silly (with the exception that you have an awful editor - in which case, get a new one)

Personally I code my CSS like this:

* { /* css */ }
body { /* css */ }
#wrapper { /* css */ }
#innerwrapper { /* css */ }

#content { /* css */ }
#content div { /* css */ }
#content span { /* css */ }
#content etc { /* css */ }

#header { /* css */ }
#header etc { /* css */ }

#footer { /* css */ }
#footer etc { /* css */ }

.class1 { /* css */ }
.class2 { /* css */ }
.class3 { /* css */ }
.classn { /* css */ }

Keeping rules on one line allows me to skim down a file very fast and see what rules there are. When they're expanded, I find it too much like hard work trying find out what rules are being applied.

Tags:

Css