Untitled

 if (isset($_POST['password']) && $_POST['password'] == 'MYPASS') { // We check here if the password entered matches 'MYPASS' and if so we set a cookie for 30 days.
        setcookie("password", 'MYPASS', strtotime('+30 days'));
        header('Location: '.$_SERVER['PHP_SELF']);
        exit;
    }
if ($_GET['q'] !== 'VALUE'){ // Here we check if 'index.php?q' has a value of 'VALUE' and if not we ask for password.
    // Simple password protection
    if (!isset($_COOKIE['password']) || $_COOKIE['password'] !== 'MYPASS') {
       echo' <html>
<head>
    <title>Password protected</title>
</head>
<body>
    <div style="text-align:center;margin-top:50px;">
        You must enter the password to view this content.
        <form method="POST">
            <input type="text" name="password">
        </form>
    </div>
</body>
</html>';
        exit;
    }
}