This post walks through the basics of the new implementation and the background you need to start experimenting. The writing-mode property, as defined in CSS3 Text Layout, is a shorthand for the ‘direction’ and ‘block-progression’ properties. Direction can be thought of as the flow of characters on a line; ‘block-progression’ can be thought of as the direction of line flow. The following table (mostly borrowed from the spec) shows its eight possible values:

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