refaz mesmo que esse "<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>My Website</title>
  <link rel="stylesheet" href="style.css">
</head>
<body>
  <header>
    <nav>
      <ul>
        <li><a href="#">Home</a></li>
        <li><a href="#">About</a></li>
        <li><a href="#">Services</a></li>
        <li><a href="#">Contact</a></li>
      </ul>
    </nav>
    <a class="full-screen-button"><button type="button" class="btn btn-secondary topbarbtn" data-toggle="tooltip" data-placement="bottom" onclick="toggleFullScreen()" aria-label="Fullscreen mode" title="" data-original-title="Fullscreen mode" aria-describedby="tooltip605001"><i class="fas fa-expand"></i></button></a>
  </header>
  <main>
    <section>
      <h1>Welcome to my website</h1>
      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed euismod, velit vel bibendum bibendum, sapien sapien bibendum sapien, vel bibendum sapien sapien bibendum sapien.</p>
    </section>
    <section>
      <h2>About us</h2>
      <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed euismod, velit vel bibendum bibendum, sapien sapien bibendum sapien, vel bibendum sapien sapien bibendum sapien.</p>
    </section>
    <section>
      <h2>Our services</h2>
      <ul>
        <li>Service 1</li>
        <li>Service 2</li>
        <li>Service 3</li>
      </ul>
    </section>
    <section>
      <h2>Contact us</h2>
      <form>
        <label for="name">Na