I'd love to see an example of super organized, tight CSS. Do you organize by location (header, footer, body), by function (typography, position data), or both, with multiple instances of the same selector? Wondering how my css stacks up and where I could improve. Thanks! (:
She splits everything in to general styles (basic HTML elements), helper styles (things like forms, notifications, icons), page structure (header, footer, layout columns etc), page components (reusable composable classes for components that occur on different pages in different combinations, such as a news teaser) and over-rides (special cases for individual pages, rarely used).
She hardly ever uses IDs, preferring classes for almost everything - because CSS written against classes can be used more than once on a page.
She uses CSSEdit's groups feature to make the CSS easier to navigate - it's all in one file. http://macrabbit.com/cssedit/
View the stylesheets on http://lanyrd.com/ and follow the link at the top to the unminified version to see annotated examples.
I checked the lanyrd.com stylesheet. I'm sorry to say but if your stylesheet is this big you are doing it wrong. 100K for a compressed stylesheet! So I'm not so sure her technique is a winner.
Lanyrd is a complex site - we have over 50 different page templates, all of which are styled using that one stylesheet. We get a lot of functionality out of that 100K. Not to mention that CSS compresses extremely well - served with gzip, the entire stylesheet is actually just 19745 bytes.
We use a far-future expires header (and serve from Amazon CloudFront), so browsers should only ever fetch the file once no matter how many pages on the site the user visits.
Oh really? Because every medium-to-large website I've ever looked at or developed has had a stylesheet that large. Facebook? Twitter? GitHub? 100k+ compressed stylesheets. Hell, even if your site is small-to-medium sized but very design-intensive, I could see you reaching that mark.
Don't worry, I'm sure all those developers are "doing it wrong" too.
Well did you check the stylesheet of Twitter for instance? Only 40K but even then.. why even that big for a simple Twitter homepage!? So I'm sorry you did not convince me. And maybe, I know it's a bold statement, they are doing it wrong.
I think it also has to do with frameworks. Sometimes frameworks spit out a lot of HTML you won't ever need. So the HTML is bloated in the first place. Then it's a hell of a job to style the mess.
When you are fortunate to control the HTML you should first start to optimize your HTML before you even start with CSS.
I think most of you who answered this reply missed the point where CSS is not HTML… ID's should be used when they suit better. The same with classes. You end up constructing semantical html which a) easier to maintain and b) won't mix the design with the content on code-time.
The problem with absolutely unique elements is that, in a complex enough website (that evolves over time), they often end up not being unique after all.
Jquery class selector is the slowest selector, avoid them as much as possible. ID selector is the fastest. So, if your application is jquery intense, better avoid css selectors.
There's less of a win in ajax from applying functionality on a class level - there aren't typically multiple selector boxes on the same page that all hit the same ajax callback.
Ideally for those you would use the html5 header, footer, and aside tags, respectively. You can use the html5 Javascript shim to enable support for those tags in IE.
Ideally, I use Sass with Compass (http://compass-style.org/). This alone is a great start to keeping things organized. One of the things I love about Sass is that it allows partials and variable declarations, which both help immensely with code organization.
Then, my code is usually organized as follows. Each section can be extracted to a partial if it gets long enough or if more separation is desired.
Framework includes and resets
Variable declarations — colors, possibly specific widths
Universal method declarations
Standard global tags — headings, p, a, ul, li, etc...
Generic form styling, usually in a dedicated partial
Layout — container, header, content, footer
Then to specific section styling
Since Sass uses indentation, I indent everything in each section within a top level tag. This really helps visually distinguish each section and gives a much less uniform look to the stylesheet which makes it a lot more scannable. If a section uses methods exclusively I'll declare them just above the top-level section tag.
I'm pretty happy with this approach. It was formed fairly organically but become more defined as I use it for more projects. It also seems to work well for both large and small projects, since partials can be used when the code starts getting long.
The biggest problem that I have with Sass is that the file/line references in your developer tools point at the compiled CSS files, and so you don't have any real reference to where in your Sass files that style is defined. Any solution for this?
There actually is; SASS has built-in functionality that will actually inject the source filename/line-number in to the generated CSS. Additionally, Nathan Weizenbaum (one of the HAML/SASS maintainers) released a Firefox/Firebug add-on that will read this and display it in Firebug like it does for traditional CSS.
Yes, Sass provides a setting that prints the source line numbers with the compiled CSS for development. I think this is on by default, but you can turn it on in the config file with:
Sass::Plugin.options[:line_comments] = true
# or with compass:
sass_options = {:line_comments => true}
Sass compiles code like this:
/* line 138, sass/screen.sass */
#navigation a:hover {...}
I guess it can be a problem sometimes, but I don't usually have issues with it and find that the organizational benefits outweigh the drawbacks by a long shot.
For me, at least in my rails project using Sass (scss): Development mode also creates inline comments in the generated CSS which describe where, in the original scss, the information can be found.
reset.css - I use eric meyer's
elements.css - Global defaults for things like body,
h1, h2, h3, p, a, input, strong. All
or almost all selectors in here are
just tag names.
layout.css - Just sets up the global layout with
containers: e.g. header, footer, left
column, right column.
blocks.css - Reusable chunks.
In addition to that, I use a separate file for each "page type". For example, 'article.css', 'index.css', stuff like that. Some larger sites merit additional files like splitting off 'forms.css', 'tabular.css', etc.
All files get concatenated and minified before serving, obviously.
That makes a lot of CSS files. Google chrome network optimization would tell you to reduce the amount of includes to speed up your site. That said that is debatable since it would be quickly cached.
As he says at the end, one would obviously not just stick a big stack of `link`s in the page. Some kind of build system/asset packager would be necessary and desired (so you aren't forced to write a huge monolithic css file that no one but your past-self can navigate :)).
I can't speak for the OP, but as I use a similar system I can venture a guess that some of the following might be worthy of chunk status...
For a website: callouts, user quote styles, tables styles [zebra stripes, etc.], feature lists, intro paragraph styles, Flash/message styles, common control styles, etc.
I made a post about it, and personally prefer it to Sass and Less: http://nylira.com/stylus-the-revolutionary-successor-to-css/ The hardcore abbreviation mixins in my post seem to offend some coders. When you work in CSS and HTML hours every day though, every character saved adds up to a huge productivity boost.
My current project has 30 directories with 73 partial Sass files, which compile down to one 320kb file.
As to your question, I organize my partials based on controller and url structure.
My current project has 30 directories with 73 partial Sass files, which compile down to one 320kb file.
Isn't that a lot to download? That's like 2 seconds on average to download that file in the U.S., and probably in the 10 seconds or higher range for a lot of folks. I guess if the download is delayed to after some kind of engagement (sign up, etc) it's not a big deal?
Is 320K of CSS really necessary? (legitimately asking)
I'm working on a few relatively complex web apps where the CSS download time don't come to anywhere near that size. In my world (mobile devices, in particular) 320k would be totally unacceptable. 100k is about the point where I start re-evaluating my design.
After many years doing CSS my best workflow has come to this:
reset.css //for resetting browsers
grid.css //if I'm using a css framework
global.css //styles that are shared across the site
section.css //styles that pertain a specific section. The name of the file varies, i.e. "about.css".
You need a good code editor that allows you to open files without tabbing or reaching for the mouse, I use Textmate's Command T to switch fast among my files.
reset.css There's a bunch around, I use the one from htmlboilerplate.com, but there's many good ones available. (Eric Meyer's). You will almost never touch this file.
grid.css I only use this occasionally, when I'm working on sites where the grid is very clear and I take out all the stuff I'm not going to use. I usually go for a three col version of 960.gs and trim it to about 12 lines of css. Never touch this.
global.css Here you put your nav, your footer, you body styles, etc. I think that separating by colors and typography doesn't make sense, because you usually change a widget's appearance.
section.css I count on the body tag having a classname, so I can have body class="about" and then do...
.about section.photo {...}
This way you never override your styles accidentally.
Miscellaneous I avoid the one declaration per line convention when I have similar styles and I want to be able to read them in a table format, i.e.
I usually start from the most generic to the more specific, but I don't worry too much about code order because in the end I just do a search and reach it in no time.
My format takes up less vertical space in the editor. Sometimes, I can get my entire CSS file into a single page on the screen, reducing the amount of time I spend scrolling and searching. I do split lines when they go off the edge of the space, as seen in the .baz example.
I prefer the latter. It's more readable IMO. If file size is an issue, I just use a CSS compressor. Also, it's not too hard in finding selectors, most IDE's or text editors have a "Find" command to locate a selector. That's my 2 cents.
This isn't about file size at all, it is about being able to see as much CSS as possible at one time.
My screen is wide, my editor is wide, my code is fairly wide, but the standard format for CSS is really narrow. Every time I see the vertical format in my editor, easily 80% of the window space is completely empty, and otherwise useless, and 80% of the CSS is not on the screen and I have to page up and down, or search, to find stuff.
This is a workflow optimization that works for me. It might work for others too.
I do it too and for the same reasons. Just easier to keep your head around if you can see and scan more of the file at once. I tend to list properties with the most crucial to layout first so it's easy to find major problems (e.g., float, etc).
If you're working on a project with multiple people, having the CSS properties one-per-line helps a lot with determining who changed what in your version control system.
Most of the command-line diff tools don't highlight changes within a single line, and annotation tools usually work on a per-line basis as well.
why don't you let your IDE organize your selectors? As mentioned above, CSS Edit does a great job with this. With it, you get the readability of the latter formatting system and the scanability (not a word, I know) of the former system.
I'm hoping for some good answers here, because I'd love a better way.
I always put universal elements first (body, img, @font-face, etc.), then I just organize it top to bottom by page location (i.e. header, content, sidebar, footer, etc.). I also tab-indent so that elements within another are indented and "contained" underneath, making it easy for me to move from one section to the next. I also write the CSS horizontally, only making a new line for a new element.
I should also note that I'm a n00b :-), so this could be a horrible way to do it.
With the exception of the horizontal CSS (personal preference - unless its compressed, I prefer things on new lines), I like everything you said.
(I actually find the tab-indented elements really interesting and may have to try it on my next project!)
One thing you didn't mention were comments. I've seen some css files with great commenting. For instance, comments at the top that act as an index/table of content for the css file. Very nice!
I do it more or less the same way, except I try to separate the layout from its content (I'll put #header, #content, #sidebar, #footer together, and later on define stuff that is specific to the content of e.g. #header).
Also, when having quite a few properties for a selector, it's quite difficult to read when all is on one long line, so I use new lines for each property.
I can't recommend Compass/Sass highly enough. A CSS pre-processor will completely free you to organize your CSS however you want, and more importantly, it lets you build up a library of common components (forms, buttons, etc.) that you can easily reuse and adapt for new projects.
Generally, these library files will simply contain mixins (reusable chunks of code), so they don't output anything directly into your CSS, but allow you to include the mixins in certain styles. Very useful for adding effects, rounded corners, etc. on different elements.
Keep in mind however, that mixins can be overused, adding bloat to your code. CSS does cascade, after all. You should always look to see if you can separate reusable css rules to include in markup (commonly seen with grid systems). How you balance out the convenience of keeping your css flexible vs. not littering your markup with lots of styles really depends on the project, but it's something to think about.
I have developed one very useful trick while using Sass for managing colors. Instead of assigning colors directly to an element (very hard to track down later if a change is necessary), I create color variables named after the element and attribute in question. Then in my colors.scss file, I build up my color palette, and after, list all the color variables I created in my stylesheets, setting their values to the appropriate color from the palette (with tweaks, if necessary).
// in colors.scss ---
// color palette
$red: #ff0000;
// assign colors to elements
$body-background-color: $red;
// in layout.css, for example ---
body {
background-color: $body-background-color;
}
Since Sass lends itself to lots of files, keeping all my colors and the elements they are assigned to together in one file makes them much easier to manage down the road.
I do this, but with a slight tweak: instead of naming the colors things like $red, I try to give them semantic names like $shadow, $highlight, etc. in case I end up having to pick a completely different color scheme.
Do both. If you pick a completely different color scheme, it's easier to change $highlight = $red to $highlight = $blue than to remember the hex values.
She used this approach at Facebook (and Yahoo, I think?) to successfully tidy up a huge code base of thousands of CSS files down to a more manageable few.
I attended her workshop at Webstock and since then had a chance to put it into practice on a 'get it up quick' green fields project (http://chchneeds.org.nz). I must say I was really pleasantly surprised at the way this approach just avoids a lot of the pain points, as a web developer/coder (ie not an html/css guru) I so often face when just getting the simplest things to 'work'.
I guess the hardest thing for me to get my head around to was that to make things more modular you had to let go (a tiny bit) of being so religious about 'semantic html' as a requirement for the HTML, but I think its worth it to get your CSS a whole lot more modular and 'pluggable' together.
Still a bit more work to do, IMHO, but I'm definitely going to be monitoring this project closely.
I'm really interested in the OOCSS approach, it's efficient, maintainable and modular, and although it's not perfectly semantic the trade-off is minimal. I first discovered it from the Velocity 2009 conference, and Nicole Sullivan's talk from Web Directions North - http://goo.gl/yLkby
I once tried breaking my css into files according to function (typography.css, color.css, layout.css). It ended up being a royal pain because when I added a new HTML element and I went to style it, I ended up having to duplicate the css selector for that element in three files. I also was constantly switching among the three files to work with one element's styles. So whatever you do, don't organize by function. :)
I start with a reset, then layout (block positioning), then widgets. Everything other than layout is a widget. There are no global styles. If there is one of it, it's an ID. If more, it's a class.
2) No (global) element styles! Ever!
No, not even a p { margin: xyz } or a ul { list-style-type }. Every element that cannot be referred to by class / id must look exactly like it would after the reset.
This avoids complex dependency chains where coincidence influences look. Widgets can be moved from one site to another and you actually have to think new widgets through rather than relying on the default values.
3) Avoid classes and id's as much as you can.
Have single base element with a simple but descriptive class name, and then specify the sub-elements.
For example: Instead of “div.content-title” use “#content h1″ (e.g. div#content with a h1 tag inside it).
Basically, design widgets which consist of one base element, and refer to sub-elements via longer expressions. Use indentation to separate sub-elements.
My strong preference is to maximize for human readability (=short dependency chains, descriptive widgets rather than single elements) rather than short CSS. Cascading within widget-scope is fine, but cascading with global styles should be avoided. I find that when I follow these rules, I like my CSS a lot more.
I utilize mixins heavily so I can modulize all my styling and make sure it's included in areas that are appropriate. I've learned this is the only way to handle CSS without styles getting too complicated and accidentally changing something where you didn't mean to.
Example (create a mixin that has certain styles for forms and then include it in a body.wizard page) this way I keep my CSS very dry.
General coding guidelines are horizontal. I recently switched to this. I used to do vertical and indentation but it's very hard to read with big files. I've found that it's a lot easier to read horizontal CSS.
The files with leading underscores are partials which are included in the master.sass. Note that facebox is an scss file. I just dump the CSS in it and include the partial in master.
The nice thing about sass is that it you can change output format, so you can just include all the external CSS files as partials and automatically output a single compressed files with your entire CSS.
When I work with a designer who uses CSS I use a structure like this:
In this case, the designer's CSS is dumped in the _style.scss partial, then included in master.sass. Then in master.sass I include my modifications to the designer stylesheets. That way I can leave the designer-provided CSS largely untouched and still have all the flexibility and power of Sass.
Use SASS with partials and mixins and sort them as it's more convenient for you (probably following the natural flow of descending order of your page).
SASS has helped me with organization tremendously. With SASS I keep a "typography" partial that is the basic text elements (h1, p, etc.) and font-family variables.
I also have a "colors" partial where I put variables for all my color definitions, such as $light-blue, $dark-gray, and $background-color.
> - If you think you need variables (like in SASS), you are probably thinking about it the wrong way
I've yet to see CSS code for page layout without the usual awkwardness where margin-left of some element MUST equal some other element's width minus some bar's left offset, yadayada. It's for stuff like this that variables make sense. I wholeheartedly agree that if you need a variable to colour two bars and a heading orange, you're probably doing it wrong.
The blog you refer to only has an example with colours, which is just too easy.
I think you should definitely use multiple files. By all means concatenate them and minify them for production, but I find it very helpful to have CSS files for layout, forms, and specific sections of the site or app.
CSS complexity is increasing at a huge rate and the volume of CSS for even a simple site is running at hundreds of lines. Splitting it into separate files keeps it readable and reusable.
The main reason is that including IDs makes “selector points” much more complex.
A selected with one ID will outweigh a selector with two classes for instance. This can quickly lead to complexity because you need to use a ID many places in order to override a selector that used ID.
A class only used once serves the same purpose as ID (CSS-wise), expect that you avoid a lot of problems.
I might use IDs for anchor purposes (site.com/foo#section), but I never reference it in my CSS.
The problem is that as a site grows, it's common for things that were once unique to become multiple.
Also, if you just resolve to always use classes instead of ids, then you can eliminate the cognitive overhead that comes with every new selector of, "Should this be a class or an id?".
Use tables for layout instead of CSS. Then your CSS will be more concise (essentially reduced to a theme) and less confusing (because CSS layout properties like float and position tend to cause the most confusion).
Edit: Rephrased to try and better express the idea.
- Almost all CSS goes in 1 big file. One line per selector to keep thinks clean and easy to find. Styles from external sources (like jQuery UI) go in separate files.
- Reset lines go at the top, if you use them, in a / RESET / section.
- Styles for individual HTML tags are next in the / HTML TAGS / section.
- Then a / UTILITY CLASSES / section for clearing floats, etc.
- Next comes site layout. Headers, footers, page width, etc. all go here. Just the layout though - think the grid. No real content styling yet.
- Now sections for each piece in the layout. Content styles go here. First a section for the / HEADER CONTENT /, then a big section for the / PAGE CONTENT / (vast majority of styles go here), then the / FOOTER CONTENT / styles.
Use less (http://lesscss.org/) - the JS version. Makes your code beautiful: no repetition, hierarchies, concise. Where I work we've used it for about 9 months now and there is no looking back.
I haven't used it, as there just hasn't been a project with enough lead time to experiment with something lately, but I'm fond of the idea of code generators for CSS, like CleverCSS for Python and Sass for Ruby.
Other than that, the best advice I can offer that I DO follow is that I group all HTML elements together, all IDs together, and then all classes together. Within each of those groupings, everything is in alphabetical order.
one thing to do is to place class names based on the url with your id's. the class name can be generated from the request_uri (assuming the html code is in a view/template/include).
example: <div id="container" class="contact_us">
then if you need tweaks to a specific page, just add
#container.contact_us { foo: bar... }
After reading all comments it seems there is no (universal) solution to write good HTML/CSS code. Not like in Ruby or Python or other programming languages.
Since this year I'm struggling to create a post / best practices how to code front-end but the problem is too complex (for me).
The biggest issue is how to mark up HTML to have a DRY (minimal) CSS.
And how to remember easily these mark up rules to be able to maintain anytime in the future your CSS/HTML.
If you would elaborate your naming / marking up best practices instead of suggesting frameworks/tools maybe that would help better.
1. Separate presentation from layout. For example, all common layout (margin, padding, display, positioning, floats) go in structure.css and color, border styles, background, etc. go in presentation.css. It is far more likely that you will be making presentation changes going forward rather than to your core layout.
2. Only use the minimal selectors you need:
div#features ul.feature_list li.feature a{color:red;} could be DRYed up to be .feature_list .feature a{color:red;} which will be far easier to override later.
3. Avoid !important at all costs (sometimes you can't, but try).
4. This is personal taste, but I also usually avoid IDs for styling.
5. Grid frameworks (Blueprint, etc.) are usually overkill, but syntax frameworks (LESS CSS, Compass) are fantastic.
It really boils down to experience, and knowing what you DON'T need - most people add in a ton of extra cruft and end up with hard to extend and debug spaghetti.
I usually use extra classes instead of IDs to differentiate specific chunks in cases where the may or may not be multiples in the future (e.g. you want nav at the top AND bottom of a page).
To style/highlight my example the above:
//This will not have to be modified if we want to add more nav instances
.main-nav.inline-list li{float:left;}
To style/highlight your example the above (at top and bottom of page):
//Each time you add another instance, you have to add its new id/selector (not very DRY)
#navigation.inline-list li,
#navigation_b.inline-list li{float:left;}
$('#navigation.inline-list a.selected, #navigation_b.inline-list a.selected').highlight();
Again, it's personal style, but I've never found myself saying "boy I wish I used an ID instead of an adding another class" where many times you regret the use of ID because when you ultimately need to duplicate that element, you are effecting the dryness of your CSS and Javascript. Plus, with modern selector engines the performance of ID vs class based selectors is not really going to have that big of an impact.
The times I use ID in my markup is more for sub-navigation through the page rather that styling-specific reasons.
<h2 id="chapter_two">Two</h2>
<a href="#chapter_two">Got to Ch. 2</a>
A good example of some super organized CSS is in the HTML5 Boilerplate by Paul Irish.
Found here:
https://github.com/paulirish/html5-boilerplate/blob/master/c...
I sometimes use multiple instances of the same selector, especially if a project starts getting very big. I like to separate each function of the site into it's own block after the footer declarations. It lets me stay organized during development and ensures that I can keep track of what I'm working on while I'm working on it.
Here's the order I'm currently using, which was inspired by the above:
Like many of the other commenters, I break the code into reset, global elements, layout, modules/blocks, and then special overrides if any.
I'll admit it's a personal preference, but as a team consideration I don't recommend the 'all properties on one line' approach. It's discouraged in other languages so why do it in CSS?
Definitely check out OOCSS as well as the Natalie Downe talk both posted by in the comments already.
I can't overstate how highly I recommend Sass/SCSS. It's been mentioned already as "for Ruby". Yes, you need Ruby installed to use Sass/SCSS but you do not need to be working on a Ruby project to use it. You can run "sass --watch (directory name)" from the command line and sass will automatically compile your .scss (or .sass) files to .css files upon save. Even if you're scared of the command line I assure you, it's easy! If you're a TextMate user, there's also a great SCSS bundle here: https://github.com/kuroir/SCSS.tmbundle (it was enough for me to abandon CSSEdit for good)
One thing that hasn't been discussed in this thread yet is the organization of properties within a declaration block. It's a good idea to have an approach and stick with it. Alphabetizing the properties is one approach. I wrote about my preferred approach a couple years ago here: http://fordinteractive.com/2009/02/order-of-the-day-css-prop... (also check out the SitePoint discussion linked in the "Further Reading" section of the post)
I lay my styles out in 1 file and I don't often comment them. Stylesheets cascade to much to pin them to a specific area of use - it's easier to debug them by clever naming still - sigh. IE specific files loaded after and only contain 1 or two tricky IE tweaks. Javascript /Jquery plugins sometimes come with their own stylesheets, and in those cases I'll leave them where I found them. For some of the bigger sites with very different looks and feels, I'll often have a boilerplate (reset to skeleton level) and each page or section will load in their own stylesheet. Just depends how big the site is.
* Conditionally load IE Styles if they're required
* load javascript plugin css with the plugin's preferred dir if possible
As for pipelining them, I usually just use a gzipped connection and still serve them individually, since internal image paths for backgrounds rely on the CSS path. CSS caches very nicely, so take advantage of it on the HTTP side.
I think alot of it depends what it is that you are building. My approach to would be different if it were building a large scale web app vs a website and it also depends on the team thats helping to maintain it (ie. if it were to be maintained by engineers who don't really know or care for css or a team of web devs)
I always start off with a base which consists of the misc. browser fixes and hacks + basic typography elements, rough blocking. My philosophy on formatting really follows what everyone here is saying. I really prefer horizontal lines and proper tabbing of all the sub elements because its really hard to read otherwise.
While commenting is really good and I like it, finding the proper balance is the key. When you're doing fast iteration it gets really tedious and cumbersome to go back and make sure your comments are in sync.
I've really enjoyed SASS/SCSS optionally with Compass.
It lets you compile the stylesheets while still keeping the source files separate and organized.
I've also seen the approach with one big file for the application with commented sections, however, the drawback to that approach is using a version control system with multiple editors on a large file (merge conflicts, etc).
On an MVC site, I organize by controller. There's one general file for generic cross-site stuff (header/footer, etc.), supplemented by another CSS file that shares the markup for all controller-specific pages.
This gives a max of two css files per page. For the landing page I compress the generic file along with the controller-specific css file for the default page into a single file. This speeds up the loading process while preventing too much bloat. Since the other pages are usually hit after the landing page they require only a single extra download. Any reset code can be included in there as well, although maintained as a separate file.
I doubt this approach is ideal when it comes to organizing things, but it's fairly fast when it comes to development. I design by including css in style="" and then refactoring the markup into classes once the design is complete. Saves a lot of back and forth while getting things lined up.
I also organize styles by controller/action in my Rails projects. This trick from "The Rails 3 Way" is great for assigning the correct classes to the page:
For me the biggest goal is fewer lines to organize in the first place rather than any particular scheme for grouping. What I do is:
1) Use as few separate stylesheets site-wide as possible so any contradicting or repetitive rules will be obvious.
2) Use one line per rule so I can scan the selectors quickly, then scroll horizontally if necessary
3) I prefer complex comma-separated selectors which set one or two properties to simple selectors which set many properties. Grouping in this way gets me closer to having constants, e.g. a specific hex color won't be rewritten again and again, it will just follow a complex selector list.
4) Once a selector works, I try to make it more general, e.g. "div.info { font-size: 12px }" can probably just be ".info { font-size: 12px }". More general rules will apply in more cases, so fewer overall rules will be necessary.
The system I came up with is A table of contents that makes it easy to jump to specific styles.
First the global styles, then different things like Header, Navigation, Main Content, Right-hand-side-doodad, Widgets, Footer, etc.
Then create a Table of contents at the top and give each section a unique identifier, FEDCBA-Head, FEDCBA-Nav, etc. Go down to each group and put in a comment saying "Start of Navigation CSS <FEDCBA-Nav>".
Now you can look in the table of contents and do a quick file search on the unique identifier, and be taken right to the CSS you're looking for.
I generally make the table of contents a lot more detailed, and it has an upkeep cost, but it's well worth it when the CSS file gets big.
(this is just an example, assume the classes are for div's)
If I have multiple CSS files, I may just call one (style.css) in the <head> of HTML document. Then within the style.css, I can just make a list of the documents using @import.
((by the way, this didn't come out the way I expected on here))
I write general styles like definitions for *, a, p, ul etc first and after that I put everithing in DOM order when possible. Starting at the startpage of the website/project.
Within the selectordefinitions I write general definitions like width, heigt, displaytype and position (top/left.. margin, padding) first. Then contentspecific definitions like fontdefinitions. At the end I write border and background definitions.
That way it's an ease to see if an element hast a specific definitions, because I know if I'm looking for the width and the first definition is not the with then there is no width set for this element.
I write general styles like definitions for *, a, p, ul etc first and after that I put everything in DOM order if possible. Starting at the startpage of the website/project.
Within the selectordefinitions I write general definitions like width, heigt, display-type and position (top/left.. margin, padding) first. Then contentspecific definitions like font definitions. At the end I write border and background definitions.
That way it's an ease to see if an element hast a specific definitions, because I know if I'm looking for the width and the first definition is not the with then there is no width set for this element.
Drupal's CSS optimization, once turned on, will roll all of these up for you automatically, so if you aren't using Drupal you will need some sort of build system to combine and minimize everything. But I think this is a good start.
On a side note, I really like the method the Zen theme uses for CSS columns. Worth checking that out as well.
To be honest. With firebug's ability to tell me what line and css files the style on an element is coming from I don't find spending a lot of time on organization to have a ton of benefit.
While I love Firebug, I'd have to counter that organization with CSS is actually quite important (and does have its benefits!)
This is especially true when you're working either in a team environment or on a large site. The very nature of CSS (and how things cascade down) can become a nightmare when organization isn't taken into account from the start.
I agree completely, especially on a web app that is constantly growing. 2 on-the-job things that help me the most are:
1. Using the 960 grid system (or your preferred grid flavor)
2. Grouping by the following:
Body
Typography
Forms
(Other global stuff like links and buttons)
/* Layout Element 1 /
ID1 {}
ID2 {}
class1 {}
class2 {}
/ Layout Element 2 */
ID3 {}
ID4 {}
class3 {}
class4 {}
I also write my styles on one line, but that's just personal preference. I find it easier to scan down for the selector, then across for the property I want. I definitely don't do it for aesthetics or file size ;)
I typically generate css with php, usually in the header but sometimes in a linked file. Using this method I can easily alter site wide color or fonts, etc or feed the style atrributes from a database. This method also allows me to create blocks of css for different page elements and include them as needed - forms, menus, etc - or dynamically include definitions when conditions are met. This offers a lot of flexibility in terms of organizing and making changes to the css.
I tend to build all my DOM in object oriented javascript, and always give the root element of a UI component the same class name as the name of the JavaScript class. See eg https://github.com/marcuswestin/Focus/blob/master/js/ui/pane.... The CSS selectors then mirror the structure of thr JavaScript files as well as the hierarchy of the resulting UI.
As for the grouping o selectors, i try not to reuse much code so cascading will not mess stuff up, i'd rather make big css than fragile css. I also try to group code on a per section basis… just remember i do have a typography stylesheet which makes most of the stuff readable and pretty before the glitz rolls in.
The best suggestion I can give is to break up your CSS into multiple files. If you have a "projects" page, make a "projects" CSS file for style definitions specific to that page. I keep the overall layout elements together. I typically also have a "forms" CSS file just for buttons, form layouts, and inputs.
I use a single file for each type of media (screen, print ...).
Each file has general styles first (HTML tags), IDs of layout boxes, classes to fine-tune formatting, and overrides at the bottom (if needed).
I like to keep spacing for readability (maybe minify the files when I'm finished).
Sometimes it's better to inline a style than to put it in a separate file.
I think when you find yourself writing nested selectors that are heavily dependent on the HTML structure, it's an indication that your code could be less fragile if you just used the HTML style attribute instead.
How I do it: 1 File. Single line styling. Order: Reset, html/body, header, container, footer, misc (h1, p, span, input). Indent (ie: #header { } -newline+tab- #header p {}
1. reset.css
2. global.css - reusable classes and styles for common selectors (html, body, a, etc)
3. css named per page (or type of a page) - ex. home.css / about.css / results.css / static.css
* I usually add a class / id to the body and use that as my first selector on the page-level css. This allows me to combine all + minify for production
ySlow recommends at most 3 stylesheets, and with good reason: the HTML headers and request times can drastically slow a site down.
By simply organizing the structure of the file well, you can have a easy to navigate css file. Of course there may be a few extra style sheets; ie.css, section specific.css, print.css and mobile.css.
http://lanyrd.com/2008/barcamp-london-5/sg/
She splits everything in to general styles (basic HTML elements), helper styles (things like forms, notifications, icons), page structure (header, footer, layout columns etc), page components (reusable composable classes for components that occur on different pages in different combinations, such as a news teaser) and over-rides (special cases for individual pages, rarely used).
She hardly ever uses IDs, preferring classes for almost everything - because CSS written against classes can be used more than once on a page.
She uses CSSEdit's groups feature to make the CSS easier to navigate - it's all in one file. http://macrabbit.com/cssedit/
View the stylesheets on http://lanyrd.com/ and follow the link at the top to the unminified version to see annotated examples.