body {
    font-family: 'Segoe UI', Arial, sans-serif;
    background: #222;
    color: #fff;
    text-align: center;
    margin: 0;
    padding: 0;
}
h1 {
    margin-top: 20px;
}
#gameCanvas {
    background: #111;
    border: 2px solid #4caf50;
    margin-top: 20px;
    display: block;
    margin-left: auto;
    margin-right: auto;
}
#score {
    margin-top: 15px;
    font-size: 20px;
}
#tip {
    margin-top: 10px;
    font-size: 16px;
    color: #ffd700;
}