body {
    max-width: 650px;
    margin: 40px auto;
    padding: 0 10px;
    font: 18px;
    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
    }
}