Internet Explorer 8 is the most Cascading Style Sheets (CSS)-compliant release yet. This topic is composed of a comprehensive list of the changes to CSS support in Internet Explorer 8 Beta 1.

• Data URI — This mechanism allows a Web page author to embed small entities directly within a Uniform Resource Identifier (URI), rather than using the URI to identify a location from which to retrieve the entity. This is primarily of interest for small images (such as a bullet) used within CSS or layout.
• Floats — Many changes have been made to float behaviors, fixing many of the most troubling float issues encountered with prior versions of Internet Explorer, including those caused by the requirement of the hasLayout property. The hasLayout functionality has been removed in Internet Explorer 8. Following are some of the fixed issues:
  • Cleared elements don't clear other nested floats when they don't share a parent
  • Cleared elements after floats have doubled top padding
• Margin collapsing — Many changes have been made to margin collapsing, fixing many of the most troubling collapsing issues encountered with prior versions of Internet Explorer, and bringing margin collapsing into compliance with the CSS, Level 2 Revision 1 (CSS2.1) specification.
• New Pseudo-classes — The following are new to Internet Explorer 8:
  • :before and :after— In conjunction with the new content rule, authors can describe dynamic ("generated") content to appear before and after elements in the document tree.
  • :focus — This pseudo-class applies while an element has input focus.
• outline — Enables elements to be highlighted without affecting their size. The outline is a shorthand property for outline-color, outline-style, and outline-width.
• Printing — The following properties have been added:
  • page-break-inside
  • widows
  • orphans
• Table Layouts — For many years, tables were the preferred layout mechanism on the Internet. With Internet Explorer 8, it is now possible to apply table-style formatting to non-table elements using the display attribute. In practice, CSS tables are more permissive than HTML markup; tables created with CSS rules will nest elements to become valid, whereas tables created with HTML will close containers to avoid unexpected nesting.
• text-decoration— Overline behavior now conforms to the CSS 2.1 specification.
• New support for the following:
  • The separated borders model (border-spacing)
  • Caption position and alignment (caption-side)
  • Automatic counters and numbering (counter-reset and counter-increment)
  • CSS3 Ruby Module  (display styles)
  • List properties — additional list-style-type values
  • white-space — pre-wrap, pre-line values
  • z-index — Specifying the stack level (auto)