a,
a:visited {
    border-bottom: 4px solid var(--link-underline);
    color: var(--link);
    text-decoration: none;
    transition: 0.8s;
}

:root {
    /* light theme defaults */
    --bg: #eee;
    --text: #222;
    --muted: #666;
    --link: #d65600;
    --link-underline: #ffc7a1;
    --hr: #cccccc;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #222;
        --text: #eee;
        --muted: #bbb;
        --link: #ffb276;
        --link-underline: #6b2e00;
        --hr: #2b2b2b;
    }
}

a:hover {
    border-color: var(--link);
}

body {
    background: var(--bg);
    color: var(--text);
    font-size: 24px;
    margin: 8rem auto;
    max-width: 800px;
    width: 100%;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: Georgia, Times, serif;
    text-align: left;
}

hr {
    border: 0;
    border-top: 1px solid var(--hr);
    display: block;
    height: 1px;
    margin: 1em 0;
    padding: 0;
}

html {
    font-family: Arial, sans-serif;
    font-size: 62.5%;
    /* makes 1.6rem = 16px */
}