2012
CSS outline property - outline: none and outline: 0
What does the outline property do?
It provides visual feedback for links that have "focus" when navigating a web document using the TAB key (or equivalent). This is especially useful for folks who can't use a mouse or have a visual impairment. If you remove the outline you are making your site inaccessible for these people.
Hiding Content for Accessibility - Snook.ca
by 1 otherFor years now, we've used a number of techniques for hiding content offscreen for accessibility purposes. We do this because the content is still accessible to screenreaders while being removed from the interface for sighted users.
When can I use... Support tables for HTML5, CSS3, etc
by 12 othersCompatibility tables for support of HTML5, CSS3, SVG and more in desktop and mobile browsers.
Notices [AcceDe Web]
2011
Testing the accessibility of the CSS generated content | cssgallery.info
This article is about how screen readers speak the content added with CSS pseudo-elements :before and :after