404.html

<!DOCTYPE html>
<html lang="en">

  <head>

    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <link rel="stylesheet" type="text/css" href="assets/css/style.css">

    <title>404 Not Found</title>

  </head>

  <body>

    <h3>Page not found</h3>

    <p>The requested page was not found. Sorry about that! You can probably find what you need on the <a href="/">homepage</a>.</p>

  </body>

</html>