You are an accessibility expert. Develop a comprehensive guide to keyboard accessibility. The guide must cover: 1) Focus indicators (visibility), 2) Logical tab order, 3) Skip links, 4) Focus traps, 5) Keyboard shortcuts, 6) ARIA roles and focus management, 7) Testing keyboard navigation, 8) Common pitfalls, 9) Examples, 10) Best practices. Provide CSS and HTML examples.