A file that can be included by reference in a Web page and that specifies typographic style for HTML elements. A user's browser determines what fonts to use to display elements, how to space those elements, etc., by reference to the CSS, but it can only use fonts that are available on the user's computer. The style definitions in a CSS typically provide a ranked list of choices in order to help ensure that at least one acceptable font be available, for example, "Arial, Helvetica, Sans-serif."
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