body {
    font-family: system-ui, sans-serif;
    background: #f9f9f9;
    color: #222;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    margin: 0;
    text-align: center;
}

.center {
    padding: 2rem;
    max-width: 600px;
}

h1 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

p {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
}

.btn {
    background: #0070f3;
    color: white;
    text-decoration: none;
    padding: 0.75rem 1.25rem;
    border-radius: 6px;
    font-weight: bold;
}