What is the most important CSS on the page? The styles that affect what you can see immediately. Chances are, that is far less CSS than your entire stylesheet(s). What if you could serve just that CSS right away rather than your entire (blocking) stylesheet? Paul Kinlan shares an idea.
A rich HTML popup content area that works when you click a link/button (rather than hover like tooltips work). This uses a bunch of CSS3 and the functionality is also handled purely with CSS, although we discuss that at the end.