Add Preflight by Tailwind CSS

• https://tailwindcss.com/docs/preflight
• https://unpkg.com/tailwindcss@3.4.1/src/css/preflight.css
• https://github.com/tailwindlabs/tailwindcss/blob/v3.4.1/src/css/preflight.css
• https://tailwindcss.com/docs/theme#referencing-other-values
• https://tailwindcss.com/docs/preflight#accessibility-considerations