<?php http_response_code(404); ?>
<div class="page-404">
  <div class="error-code">404</div>
  <h1 class="error-title">Page Not Found</h1>
  <p class="error-description">
    The page you're looking for doesn't exist or has been moved. 
    Let's get you back on track.
  </p>
  <div class="error-actions">
    <a href="javascript:history.back()" class="back-button">
      ← Go Back
    </a>
    <a href="index.php?page=home" class="home-button">
      🏠 Go Home
    </a>
  </div>
</div>