:root {
    --app-width: 720;
    --app-height: 720;
    --bg-color: rgb(32, 32, 32);
}
html, body, * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html, body {
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}
body {
    padding: .5rem;
    background-color: var(--bg-color);
}
body main canvas {
    width: 100% !important;
    height: 100% !important;
    object-fit: contain;
    max-width: calc(var(--app-width) * 1px);     
    max-height: calc(var(--app-height) * 1px);
    aspect-ratio: calc(var(--app-width) / var(--app-height));
}