The specification for Basic User Interface, one of the 29 modules that constitute CSS3 (the next generation of the Cascading Style Sheets formatting language) has been published as a Last Call Working Draft.

The major changes between this draft and the previous (2 August 2002) draft include the addition (based on input from the XForms working group) of some new user interface selectors:

• :in-range and :out-of-range states (pseudo-classes)
• ::repeat-item pseudo-element
• ::repeat-index pseudo-element

A list of all the major changes is provided near the beginning of the document.

The Basic User Interface specification details CSS properties for controlling the "interactive, dynamic aspects of Web pages" -- that is, for controlling the look and feel of the user-interface parts of pages; for example:

• changing the look (outline and color) of an element (e.g., a form control) based on its current state (e.g., whether it's checked, active, being hovered over, has focus, etc.)
• making an element (e.g., a text box on a form) horizontally/vertically resizable
• controlling the cursor shape based on the element it is currently hovering over
• specifying a keyboard equivalent to activate a particular element

The CSS Working Group is inviting public comment on the Last Call draft through 31 July 2003. Comments should be posted to the www-style@w3.org mailing list (archive).

The CSS "Under Construction" page provides a handy "roadmap" table with links/status info for the various CSS3 module specifications. The Introduction to CSS3 document is also a good place to start.

A list of other current W3C Last Call Working Drafts is also available.