body {
    background: #0b0b0c;
    color: white;
    font-family: Arial;
    text-align: center;
}
header {
    background: #900000;
    padding: 15px;
    font-size: 28px;
    font-weight: bold;
}
.nav a {
    display: inline-block;
    margin: 10px;
    padding: 12px 18px;
    background: #222;
    border-radius: 10px;
    text-decoration: none;
    color: white;
}
.modal {
    display: none;
    position: fixed;
    top:0;left:0;width:100%;height:100%;
    background: rgba(0,0,0,0.7);
}
.modal-content {
    margin: 15% auto;
    background: #111;
    padding: 20px;
    width: 300px;
    border-radius: 12px;
}