To improve SEO and eliminate duplicate content, the HTML needs to be rewritten. All class and CSS styles should be removed. The specific changes needed depend on the original HTML. A common approach is to consolidate similar content into unique sections with descriptive headings and subheadings. Redundant text should be removed or rewritten to express the same information in a different way. Ensure each page has a unique title, meta description, and header tags. Use canonical tags to direct search engines to the preferred version of duplicate pages. Finally, check for and fix broken links.