errorpages/404.html

<!DOCTYPE html>
<html lang="en" dir="ltr">
<meta charset="utf-8">
<title>Not Found</title>
<link rel="shortcut icon" href="//foundation.wikimedia.org/favicon.ico">
<style>
* { margin: 0; padding: 0; }
body { background: #fff; color: #202122; font: 0.938em/1.6 sans-serif; }
.content { margin: 7% auto 0; padding: 2em 1em 1em; max-width: 640px; }
img { float: left; margin: 0 2em 2em 0; }
a img { border: 0; }
h1 { margin-top: 1em; font-size: 1.2em; }
p { margin: 0.7em 0 1em 0; }
a { color: #36c; text-decoration: none; }
a:hover { text-decoration: underline; }
em { color: #72777d; font-style: normal; }
@media (prefers-color-scheme: dark) {
  body { background: transparent; color: #dfdedd; }
  a { color: #9e9eff; }
  em { color: #8d8882; }
  #logo { filter: invert(1) hue-rotate(180deg); }
}
</style>
<meta name="color-scheme" content="light dark">
<div class="content" role="main">
<a href="https://www.wikimedia.org"><img id="logo" src="https://www.wikimedia.org/static/images/wmf.png" srcset="https://www.wikimedia.org/static/images/wmf-2x.png 2x" alt=Wikimedia width=135 height=135></a>
<h1>Page not found</h1>
<p>The requested URL was not found on this server.</p>
<p>You can visit the <a href="/">Main Page</a>.</p>
</div>
</html>
<!-- 404.html -->