CSS Standards

A specification is not a manual. There is no excuse for badly written prose and please complain if you find some. But specs do target a specific audience. If you need some guidance, read Understanding the CSS Specifications.

Current Specifications

Cascading Style Sheets (CSS)

The following documents constitute the official, formal definition of Cascading Style Sheets (CSS). We recommend starting with the current CSS Snapshot.

CSS Snapshot 2007
Defines (by referencing the appropriate specifications) CSS Level 1, CSS Level 2, and beyond, as of 2007.
CSS Level 2 Revision 1 (CSS2.1) and errata
Defines CSS Level 2 and forms the foundation for CSS Level 3.
Selectors Level 3
Defines selectors, which are used to select elements in an HTML or XML document.
CSS Color Level 3
Specifies the color-related aspects of CSS.
CSS Basic User Interface
Defines some features for styling interactive aspects of Web pages.

Cascading Style Sheets (CSS) Profiles

Profiles define a subset of CSS appropriate for a particular type of user agent.

CSS TV Profile 1.0
Defines a subset of CSS tailored to the needs and constraints of TV devices.

CSS-related APIs

Simple API for CSS (Parsing)
SAC 1.0 is a standard interface for CSS parsers that is designed to work with CSS (all levels) and CSS-derived languages.
Document Object Model (DOM) Level 2 Style
DOM Level 2 Style is a platform- and language-neutral interface that allows programs and scripts to dynamically access and update the linking and content of style sheets.

Upcoming Specifications

The following specifications are still in the process of development. You can learn more about this work on the current work page and participate by contributing to the discussion and development of the CSS specs and test suites.

CSS Modules Current Upcoming
CSS Advanced Layout Working Draft Working Draft
CSS Backgrounds and Borders Level 3 Working Draft Working Draft
CSS Basic Box Model Level 3 Working Draft Working Draft
CSS Cascading and Inheritance Level 3 Working Draft Working Draft
CSS Fonts Level 3 Last Call Working Draft
CSS Generated and Replaced Content Level 3 Working Draft Working Draft
CSS Generated Content for Paged Media Working Draft Working Draft
CSS Grid Positioning Working Draft Working Draft
CSS Lists Level 3 Working Draft Working Draft
CSS Multi-column Layout Working Draft Working Draft
CSS Namespaces Working Draft Last Call
CSS Paged Media Level 3 Last Call Candidate Recommendation
CSS Ruby Candidate Recommendation Working Draft
CSS Speech Level 3 Working Draft Working Draft
CSS Tables Level 3 Working Draft
CSS Text Level 3 Working Draft Working Draft
CSS Text Layout Level 3 See Text Working Draft
CSS Values and Units Level 3 Working Draft Working Draft
CSS Web Fonts Level 3 Last Call Working Draft
Behavioral Extensions to CSS Working Draft Working Draft
Media Queries Candidate Recommendation Working Draft
CSS Profiles Current Upcoming
CSS Mobile Profile 2.0 Last Call Candidate Recommendation
CSS Print Profile Last Call Candidate Recommendation
CSS APIs Current Upcoming
CSS Object Model Level 3 Working Draft

Obsolete Specifications

CSS Level 2 (1998)
This CSS2 specification is obsoleted by the CSS2.1 specification, which incorporates all the CSS2 errata and many other fixes and clarifications.
CSS Level 1 (1996/1999)
This CSS1 specification is obsoleted by the CSS Level 1 definition in the CSS Snapshot, which states that CSS Level 1 is defined as all the features listed in this CSS Level 1 specification using the definitions in CSS2.1.
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