Html Tailwind Guideline: Layout — Container max-width. Description: Limit content width for readability. Do: max-w-7xl mx-auto for main content. Don't: Full-width content on large screens. Good Example: max-w-7xl mx-auto px-4. Bad Example: w-full (no max-width). Severity: Medium. Docs: https://tailwindcss.com/docs/container.