<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>VPN Required</title>
<style>
body { font-family: sans-serif; background: #111827;
color: white; display: grid; place-items: center;
min-height: 100vh; margin: 0; text-align: center; }
main { padding: 32px; }
h1 { font-size: 32px; }
p { color: #9ca3af; }
</style>
</head>
<body>
<main>
<h1>VPN Required</h1>
<p>This service is only accessible from the internal network or via VPN.</p>
</main>
</body>
</html>