body {
    margin: 0;
    padding: 20px;
    font-family: Arial;
    background: #f4f4f4;
}

h1 {
    margin-top: 0;
}

nav button {
    padding: 10px 15px;
    margin: 5px;
    border: none;
    background:#222;
    color:#fff;
    border-radius:6px;
}

.page {
    background:#fff;
    padding: 15px;
    border-radius:10px;
    margin-top: 10px;
}

.toggleDark {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background:#000;
    color:#fff;
    padding:10px;
    border-radius:10px;
}

/* Dark mode */
body.dark { background:#111; color:#eee; }
body.dark .page { background:#1a1a1a; }
body.dark nav button { background:#333; }