B. Count the number of ID attributes in the selector and apply the value 0,1,0,0 for each or A=0, B=1, ... help to illustrate each of the CSS selectors and specificity in action.

Editor’s note: This How To assumes a basic understanding of HTML. Along with HTML and JavaScript, CSS forms the foundation of the open Web. These three technologies power just about every ...

Understanding how browsers parse CSS and render websites is an important first step towards writing more efficient code. In this first piece on efficient CSS, we look at selectors, how the browser ...