index.html

<!doctype html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link rel="stylesheet" href="style.css" />
    <title>Guess My Number</title>
  </head>
  <body>
    <header class="header">
      <h1>Guess My Number</h1>
    </header>

    <main>
      <section class="section-main">
        <article class="box">
          <div class="box-header">
            <button class="btn again">Again!</button>

            <h2>(Between 1 and 20)</h2>
          </div>
          <div class="box-middle">
            <h2>Guess A Number!</h2>
            <div class="number">?</div>
          </div>
          <div class="box-footer">
            <div class="box-footer-left">
              <input type="number" class="guess" />
              <button class="btn check">Check!</button>
            </div>
            <div class="box-footer-right">
              <p class="message">Start guessing...</p>

              <p class="label-score">💯 Score: <span class="score">20</span></p>
              <p class="label-highscore">
                ✌ Highscore: <span class="highscore">0</span>
              </p>
            </div>
          </div>
        </article>
      </section>
    </main>

    <!-- The JS script file  -->
    <script type="text/javascript" src="script.js"></script>
  </body>
</html>