Christian Heilmann

Posts Tagged ‘thoughts’

Some thoughts on CSS – a foreword

Tuesday, March 13th, 2012

The other day I was asked to write a foreword for a book on CSS by someone I inspired, so here is what I wrote.

When Cascading Style Sheets got supported by browsers, a lot of things changed. I remember the first article I read about them was saying that using them could increase the speed of your web sites tenfold and your development and maintenance time will be cut in half.

That was totally true, as this was a time when connecting to the internet sounded like Dubstep sounds now and 56k connections were luxury. In order to style things we needed images, background colours, table layouts and font elements. And of course lots and lots of spacer gifs and   to create padding.

Fast forward to now, and you will see that it is almost impossible to think of any web design without CSS. In the last year alone we got so many cool new features to play with that animation and transformations with JavaScript can soon be as forgotten as spacer gifs are now. We can set colours in various formats, we can add our own fonts, create patterns and gradients, we have transformations and transitions and we can define animations. We can generate content in CSS in case we need it only for a visual effect and we have all kind of interaction selectors when the user hovers over something, clicks it or even selects text in the page.

A lot of this comes with a price: we have to repeat a lot of settings to support all the browsers (and those coming in the future) and there are differences in implementation that can make our life harder. This, however, is a temporary problem. Sadly enough it doesn’t stop people from repeating mistakes of the past like favouring one browser without providing fallbacks for others and older ones. We did that already with IE6 which is why now a lot of our products are hard to maintain and upgrade.

In general, the ubiquity of CSS in our development world made it a bit less magical. We actually see it as a given and there is hardly any thought and documentation out there how to write well-structured, clean and simple CSS that does the job. Our high speed connections, caching and a plain disregard of CSS amongst “real developers” made our style sheets a dumping ground rather than getting the same love we give our Python or JavaScript. Want proof? Github, a rather simple looking site loads 400KB of CSS in over 20000 lines of code. Facebook used to have over 2MB of CSS before some friends of mine re-engineered the CSS using an “object oriented approach” and last but not least a new bug in Internet Explorer got discovered: it only loads 32 external style sheets before giving up.

Now, as an old-school, hand-craft developer I shook my head at the mere thought of 32 style sheets, but the fact of the matter is that CMS and other systems create a sheet for each module on a large site and instead of concatenating them just add them to the template as a new link element.

I once wrote a 300 line CSS document for a massive, international web site. When I left the company, I looked at it half a year later and it grew to a whopping 3800 lines with massive selector chains and very specific class names like “headingright3c6bold”. In order to create a visual change the poor maintainers who obviously had no clue how CSS works (or didn’t care) added random HTML elements to the templates to have a handle to increase the specificity and many other crimes against CSS were committed before my very eyes.

That is why I am happy that there is a new movement, a desire to clean up the CSS we write and make it snappy and fast again, going full circle to the original promise of CSS.

This book is part of this movement, and the writer shows insight, foresight and interest in a topic that many consider too confusing to care about. I for one am very happy to see it come out and hope that by reading it you get inspired to put the art and the magic of speed back into your style sheets.