I always try to use the single-line approach to declare e.g. the margin of an element.
margin: <margin-top> || <margin-right> || <margin-bottom> || <margin-left>
I was wondering if this actually runs faster than the four-line approach.
margin-top: <margin-top>;
margin-right: <margin-right>
margin-botttom: <margin-bottom>
margin-left: <margin-left>