When you edit an external CSS style sheet, all documents linked to that CSS style sheet are updated to reflect those edits. You can export the CSS styles found in a document to create a new CSS style sheet, and attach or link to an external style sheet to apply the styles found there.
You can, of course, attach to your pages any style sheet that you create or copy into your site. In addition, Dreamweaver is shipped with prebuilt style sheets that can be automatically moved into your site and attached to your pages. For information about using the design style sheets that come with Dreamweaver, see Creating a document based on a Dreamweaver design file.
For information about applying a style, see Applying a class style.
For instructions, click the Help button in the dialog box.