Task #1


<?php
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);
?>
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CMS - SYSTEM</title>
</head>

<body>
    <div class="navigation">
        <?php
        include "navigationbar.php";
        $page = isset($_GET["page"]) ? $_GET["page"] : "welcome";
        $allowed = ["cms", "welcome", "contact"];
        if (in_array($page, $allowed) && $page != "cms"):
            include "Pages/$page.php";
        elseif ($page == "cms"):
            include "$page.php";
        else:
            echo "<h2>Page not found</h2>";
        endif;
        ?>
    </div>
</body>

</html>