What exactly CSS3 is? [closed]

Question

Closed. This question needs to be more focused. It is not currently accepting answers.

---

Want to improve this question? Update the question so it focuses on one problem only by editing this post.

Closed 8 years ago.

Improve this question

Looking at w3.org, there are heaps of specs, many of them ending in Level 3, many in Level 1, etc.

So what is CSS 3? Do we have specs for CSS 3, CSS 2, and CSS 1?

When will the CSS 3 spec be marked as complete, final, and feature-frozen?

Answer 1

There is no single "CSS3" specification.

There are single specifications (W3C Recommendations) for …

CSS1:

• 1996-12-17: http://www.w3.org/TR/REC-CSS1-961217
• 1999-01-11: http://www.w3.org/TR/1999/REC-CSS1-19990111
• 2008-04-11: http://www.w3.org/TR/2008/REC-CSS1-20080411/

CSS2:

• 1998-05-12: http://www.w3.org/TR/1998/REC-CSS2-19980512/
• 2008-04-11: http://www.w3.org/TR/2008/REC-CSS2-20080411/
• 2011-06-07: http://www.w3.org/TR/2011/REC-CSS2-20110607/

But for CSS3, there is no single specification anymore. Instead, each "module" gets its own specification. For example:

• Selectors Level 3
• CSS Color Module Level 3
• Media Queries
• …

From Levels, snapshots, modules…:

The CSS working group chose to adopt a modular approach for CSS beyond level 2, where each module defines a part of CSS, rather than to write a single monolithic specification. This breaks the specification into more manageable chunks and allows more immediate, incremental improvement to CSS.

You can see all specs at http://www.w3.org/Style/CSS/current-work resp. http://www.w3.org/standards/techs/css.

So when people refer to "CSS3", they typically mean: any "new" CSS specifications that came after CSS2.1.

But note that "CSS4" (which probably means: CSS, level 4) doesn’t start when all CSS3 specifications modules are complete. Each module is (from CSS level 3 on) levelled independently:

From this level on modules are levelled independently: for example Selectors Level 4 may well be defined before CSS Line Module Level 3.

Answer 2

So what is CSS 3?

From a standards perspective, I would say that CSS 3 is anything thats designated CSS Level 3 unless otherwise defined in a lower level standard. A lot of what we call CSS 3 are still proposals. There probably is a better way to word this.

Do we have specs for CSS 3, CSS 2, and CSS 1?

• For CSS 3, it depends on what you mean by "have" , as, again, there are a lot of proposals.
• For CSS 2 (well, 2.1, W3C Recommendation 07 June 2011) => http://www.w3.org/TR/CSS2/
• For the original CSS 2 (W3C Recommendation 12-May-1998 (revised 11 April 2008)) => http://www.w3.org/TR/2008/REC-CSS2-20080411/

When will the CSS 3 spec be marked as complete, final, and feature-frozen?

Notice where I showed above that CSS 2 had a revision over 10 years after it was first introduced, and then it got updated to 2.1 3 years later. It's going to be a LONG time before CSS 3 gets to final; and when it does finally gets to "final", I think likely parts of it will be superseded by later specifications. I also don't find it improbable that it may never happen, as this "CSS Level" concept be superseded by a better versioning system.

Answer 3

CSS3 is just a convenient name, really. New CSS modules are being created all the time, and they are effectively 'ready' when you can use that code in modern browsers. Some 'CSS3' modules are in common use already, such as Selectors Level 3. Developers aren't tending to wait around for for some kind of complete, final, and feature-frozen status. Instead, they head to caniuse.com and see how well various features are supported, and decide whether or not to use them on that basis.