quest.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Quest</title>
    <link rel="stylesheet" href="css/quest.css" />

</head>
<body>
    <header>
        <div class="nav">
          <img
            src="assets/imgs/back.svg"
            onclick="location.href = 'categories.html'"
            alt="back button"
            class="back-btn"
          />
          <img src="assets/imgs/logo.svg" alt="logo" class="logo" />
        </div>
        <div class="label">
          <h2></h2>
          <h3></h3>
        </div>
      </header>
<main>

<div id="under"></div>
</main > 

<footer>
  <br>
  <br>
  <br>
</br>
<input  onclick="showMarks()"  type="submit"  id="submit">
</footer>

    <script src="js/quest.js"></script>
</body>
</html>