Personal Portfolio Webpage - Build a Personal Portfolio Webpage

Tell us what’s happening:
Describe your issue in detail here.
please help, why my navbar isn’t working.

  **Your code so far**
/* file: index.html */
<!DOCTYPE html>
<html>
<head>
  <link rel="stylesheet" href="styles.css">
</head>
<body>
  <header>
    <nav  id="navbar">
      <ul>
        <li><a href="#welcome-section">About</a></li>
        <li><a href="#projects">Work</a></li>
        <li><a href="#contact">Contact</a></li>
      </ul>
    </nav>
  </header>
  <section id="welcome-section">
    <h1>Hi I am sirine</h1>
    <p>a web developer</p>
  </section>
  <section id="projects">
    <h2>These are some of my projects</h2>
    <hr></hr>
    <a href="https://codepen.io/freeCodeCamp/full/zNqgVx" target="_blank" class="project-tile">
      <img src="https://cdn.freecodecamp.org/testable-projects-fcc/images/tribute.jpg">
      <p>
        <span>Tribute Page</span>
      </p>
    </a>
    <a href="https://codepen.io/freeCodeCamp/full/qRZeGZ" target="_blank" class="project-tile">
      <img src="https://cdn.freecodecamp.org/testable-projects-fcc/images/random-quote-machine.png">
      <p>
        <span>Random Quote Machine</span>
      </p>
    </a>
    <a href="https://codepen.io/freeCodeCamp/full/wgGVVX" target="_blank" class="project-tile">
      <img src="https://cdn.freecodecamp.org/testable-projects-fcc/images/calc.png">
      <p>
        <span>JavaScript Calculator</span>
      </p>
    </a>
    <a href="https://codepen.io/freeCodeCamp/full/mVEJag" target="_blank" class="project-tile">
      <img src="https://cdn.freecodecamp.org/testable-projects-fcc/images/map.jpg">
      <p>
        <span>Map Data Across the Glone</span>
      </p>
    </a>
    <a href="https://codepen.io/freeCodeCamp/full/wGqEga" target="_blank" class="project-tile">
      <img src="https://cdn.freecodecamp.org/testable-projects-fcc/images/wiki.png">
      <p>
        <span>Wikipedia Viewer</span>
      </p>
    </a>
    <a href="https://codepen.io/freeCodeCamp/full/KzXQgy" target="_blank" class="project-tile">
      <img src="https://cdn.freecodecamp.org/testable-projects-fcc/images/tic-tac-toe.png">
      <p>
        <span>Tic Tac Toe Game</span>
      </p>
    </a>
    <button>Show all <strong> > </strong></button>
  </section>
  <section id="contact">
    <div>
      <h1>Let's work together...</h1>
      <p>Do you like coffee as I do?</p>
    </div>
    <div>
        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
        <a href="https://facebook.com/freecodecamp" class="fa fa-facebook-square"  target="_blank">
          Facebook
        </a>
      
        <a href="https://github.com/freecodecamp" class="fa fa-github" id="profile-link" target="_blank">
        GitHub
      </a>
        <a href="https://twitter.com/freecodecamp" class="fa fa-twitter" target="_blank">
        Twitter
        </a>
      
        <a href="example@example.com" class="fa fa-at" target="_blank">
          Send a mail
        </a>
        <a href="tel:555-555-5555" class="fa fa-phone" target="_blank">
        Call me
        </a>
      
    </div>
  </section>
  <footer>
    <p>**I just trying my best...</p>
    <p>
      © Created for
      <a href="https://www.freecodecamp.com/">freeCodeCamp</a>
    </p>
  </footer>
</body>
</html>

/* file: styles.css */

  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36

Challenge: Personal Portfolio Webpage - Build a Personal Portfolio Webpage

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