body {
    max-width: 650px;
    margin: 40px auto;
    padding: 0 10px;
    font: 18px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
    color: #444;
}
h1,
h2,
h3 {
    line-height: 1.2;
}
@media (prefers-color-scheme: dark) {
    body {
        color: #c9d1d9;
        background: #0d1117;
    }
    a:link {
        color: #58a6ff;
    }
    a:visited {
        color: #8e96f0;
    }
}