canvas {
    width: 50%;
    height: 50%;
}
@media screen and (max-width: 700px) {
    canvas {
        width: 75%;
        height: 75%;
    }
}

td {
    text-align: center;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Noto Sans JP", "Segoe UI","Hiragino Sans","Meiryo";
}