Over the last 10 years or so I’ve done a ton of technical editing work. I’ve helped with CSS articles and CSS books for various online and print publications. One of the things that comes up often when I make suggestions is the difference between a CSS rule and a CSS ruleset.
In most cases, almost all authors use the term “CSS rules” to refer to the blocks of CSS that include the selector and the CSS declarations. Is this correct?
Over on CSS-Tricks, Chris breaks down what some in the industry have said on the possibility that there will one day be a CSS4. The latest article that Chris references is one by a well-respected member of the community, Peter-Paul Koch (“PPK”).
In brief, PPK believes in initiating some sort of marketing gimmick wherein we basically try to repeat the success of the buzz surrounding “CSS3” by pushing the name “CSS4”.
If you’ve been writing CSS for some time, then you’ve certainly done something similar to the following, and likely multiple times in a single stylesheet:
The lone declaration in the rule set above is what’s commonly referred to as a font stack. This line defines the font that the browser should use for the specified element (in this case, for the <body> element). The stack is “Arial, Helvetica, sans-serif”. This instructs the browser to take the following steps:
In most cases, when you place an element on the page in your markup, if you don’t specify any special styles, it will occupy exactly the same space that it appears to occupy visually.
In other words, if you place a box sized at 200px by 200px on your page, anything you place after it in the source order, with no further styles added, will occupy the space below or beside the green box, outside of those set boundaries.
But not everything on an HTML page occupies space that is honored by other elements. I thought it would be interesting to list and describe all the things in CSS that don’t occupy this kind of physical space in an HTML document.
Now that the numbers for IE6 and IE7 usage are diminishing rapidly, more and more development teams are starting to weed out support for those older browsers.
Most readers will probably have removed IE6 completely from the equation and soon IE7 will follow. Despite IE8 still having the highest share of any single browser version, the demise of IE6/7 now allows us to be more creative with CSS selectors.
This post will provide a comprehensive review of support for CSS3 selectors in the most troublesome browsers (guess which ones?). Each selector links to the appropriate location in the CSS3 spec.