ARCHIVED: What is CSS?

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Cascading style sheets (CSS) are used to determine the appearance of HTML pages in a browser. They provide an easy way to change the visual appearance of a group of HTML files without changing each individual file. CSS allows the separation of web page content (i.e., the text of a page) from the way that the content is displayed (i.e., the font, size, and color of the text). The standards for CSS are maintained by the World Wide Web Consortium (W3C).

Many WYSIWYG web design programs such as Adobe Dreamweaver use CSS behind the scenes to manage the style and formatting chosen by the user. For more, see the "Web authoring tools" section of ARCHIVED: For HTML, what editing software is available?

CSS files can be edited manually with a text editor like Notepad or TextEdit, and can be identified by their .css file extension. To learn how to use CSS, see the W3Schools CSS Tutorial.

Not all graphical browsers implement all the properties of the complete specification for CSS; even those that do sometimes render them very differently. If you develop pages using CSS, be sure to test them in a wide range of browsers. To learn how different browsers handle CSS features, see the W3C's CSS Browsers reference.

For more information about CSS, see: