body{margin:0;font-family:Arial,sans-serif;background:linear-gradient(135deg,#4facfe,#00f2fe);display:flex;justify-content:center;align-items:center;height:100vh}.container{background:#fff;padding:40px;border-radius:15px;text-align:center;box-shadow:0 10px 30px rgba(0,0,0,.2)}button{background:#0078ff;color:#fff;border:none;padding:12px 25px;border-radius:8px;cursor:pointer}#message{margin-top:20px;color:green;font-weight:bold}