<?php
    session_start();
?>
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body style="background-color: <?php echo $_COOKIE["color"]?>;">
    <form action="index.php" method="POST">
        <input type="hidden" name="logout" value="1">
        <button type="submit">
            Kijelentkezés
        </button>
    </form>
</body>
</html>