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HTML and CSS

HTML: Guidelines

National Library of Medicine (NLM) Web pages must be authored in structural HTML5. Page authors should follow accessibility guidelines in compliance with Section 508 and the WAI so that our site’s content will be made available to the widest possible number of people, browsers, and Internet devices. In addition, all HTML must validate.

CSS: Style Sheets & Tips

Web sites and web-based applications must use valid Cascading Style Sheets (CSS) to control typography, color, and other layout elements. Style sheets must be linked in a way that accommodates the capabilities of new and old browsers.

If you wish to create your own style sheets, please discuss your requirements with your NLM project coordinator.