index.html

<!DOCTYPE html>
<html lang="en">
<head>
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/normalize/8.0.1/normalize.min.css">
  <link rel="stylesheet" href="style.css">
  <title>Grad Križevci</title>
</head>
<body>
    <header class="header">
        <h1><a href="index.html">Rezervacija dvorana</h1></a>
        <nav class="flex_nav">
          <a href="index.html">Home</a>
          <a href="halls.html">Dvorane</a>
          <a href="#">O nama</a>
          <a href="register.html">Registracija</a></li>
        </nav>
      </header>

  <img src="https://images.unsplash.com/photo-1497366754035-f200968a6e72?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1350&q=80" alt="office">

  <footer>
    <h4>Grad Križevci</h4>
  </footer>
</body>
</html>