64 > (greater-than sign) is a CSS Combinator (Combine + Selector). A CSS selector can contain more than one simple selector. Between the simple selectors, we can include a combinator. There are four different combinators in CSS3: descendant selector (space) child selector (>) adjacent sibling selector (+) general sibling selector (~)
So is this @ symbol something new in CSS3, or something old that I've somehow overlooked? Is this something like where with an ID you use #, and with a class you use .? Google didn't give me any good articles related to this. What is the purpose of the @ symbol in CSS?
What is the purpose of the '@' symbol in CSS? - Stack Overflow
In CSS what is the difference between "." and - Stack Overflow
The CSS that you referenced is very useful to a web-designer for debugging page layout problems. I often drop it into the page temporarily so I can see the size of all the page elements and track down, for example, the one that has too much padding which is nudging other elements out of place.
What does an asterisk (*) do in a CSS selector? - Stack Overflow
In CSS there are some default styles applied to every web page in addition to your styles. These default styles define certain and values for elements like , etc.
css selectors - What does "*" mean in CSS? - Stack Overflow
WebKit is a HTML/CSS web browser rendering engine for Safari/Chrome. Are there such engines for IE/Opera/Firefox and what are the differences, pros and cons of using one over the other?