error.php

<?php
$error = filter_input(INPUT_GET, 'err', $filter = FILTER_SANITIZE_STRING);

if (! $error) {
    $error = 'Oops! An unknown error happened.';
}
?>
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Secure Login: Error</title>
    <link rel="stylesheet" href="css/main.css" />
    <link rel="stylesheet" href="css/foundation.css" />
    <script src="js/vendor/modernizr.js"></script>
    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
</head>
<body>
    <h1>There was a problem</h1>
    <p class="error"><?php echo $error; ?></p>
    <script src="js/vendor/jquery.js"></script>
    <script src="js/foundation.min.js"></script>
    <script>
        $(document).foundation();
    </script>
</body>
</html>