html { font-size: 18px; background-color: #ddeeff; color: #222; }
body { width: 80%; max-width: 900px; margin: 3rem auto 8rem; }
a { color: #54f; }
a:visited { color: #bd01bd; }
a:hover { color: #108; } 
hr { border: none; border-bottom: 1px dotted #7779; margin: 2rem 0; }
p+h1,p+h2,p+h3,p+h4,p+h5 { margin-top: 2em; }
@media (prefers-color-scheme: dark) { 
    html { background-color: #111114; color: #def; } 
    a { color: #76f; }
    a:visited { color: fuchsia; }
    a:hover { color: #ccf; }
}