How style sheets cascade

One of the fundamental features of CSS is that style sheets cascade--in other words, several style sheets may control the same document and override one other according to certain rules of precedence. You can build and embed or attach your preferred style sheet when authoring the page, but your viewers may have personal style sheets to customize the presentation of HTML pages to meet their own needs (if the browser supports this feature).

When several style sheets try to influence the presentation, conflicts may arise. These conflicts are resolved by assigning each style rule a weight. As an author using Adobe GoLive, you can assign a weight when referencing external style sheets (see Referencing external style sheets). By default, the viewer's rules weigh less than the author's rules. Consequently, if there are conflicts between the style sheets of a document loaded by the browser and the viewer's personal sheets, the author's rules will override the viewer's rules. In any case, both the viewer's and author's rules override the browser's default values.

Imported style sheets also cascade with one other, in the order they are imported. Any rules specified in the style sheet itself override rules in imported style sheets. That is, imported style sheets are lower in the cascading order than rules in the style sheet itself.

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