:root

Back to the index.

The :root pseudo-element selects the root of all blocks in the page, ie. the Initial Containing Block. In HTML this is obviously the <html> element

Test stylesheet:

:root {
	background-color: #6374AB;
	padding: 50px;
}

If the :root selector works the left and right column of the page are blue, and the white middle column is offset by 50 pixels.