Vertically Centered 404 Layout
Numeral, one line of copy, one button. The layout to reach for when you have no search index and no obvious second destination — two links beat a sitemap dump.
Create a not-found page layout, vertically centered in the viewport: a large 404 numeral as a display element, an h1 stating that the page was not found in plain language, one sentence explaining it may have moved or been deleted, and a primary Back to home button. Reuse the site header and footer so the page does not read as a different site. The route must return an HTTP 404 status, not a 200 with error copy on it, or search engines will index the dead URL. Give the h1 focus on load so screen reader users land on the error rather than the nav, and keep the numeral decorative with aria-hidden so it is not announced as a number.



