:root {
    color-scheme: light dark;
}
body {
    width: 85%;
    max-width: 75ch;
    text-align: center;
    margin: 1rem auto;
    padding-top: 20px;
    font-family: monospace;
}
hr {
    border: 0;
    padding: 1em 0;
    position: relative;
}
hr::before {
    content: attr(data-content);
    position: absolute;
    padding: 0 1ch;
    line-height: 1px;
    border: solid;
    border-width: 0 99vw;
    transform: translateX(-50%);
}