body {
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
    margin: 0;
    padding: 20px;
}
.container {
    max-width: 420px;
    margin: auto;
    background: white;
    padding: 20px;
    border-radius: 4px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    text-align: center;
}
.game-wrapper {
    position: relative;
    width: 100%;
    padding-top: 100%;
}
canvas {
    background: #000;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: block;
}
#score {
    font-weight: bold;
    margin-bottom: 10px;
}
.instructions {
    color: #555;
    margin-bottom: 10px;
}
.start-instruction {
    color: #555;
    margin-bottom: 10px;
}
button {
    margin-top: 10px;
    padding: 6px 12px;
}