@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #111;
    --fg-color: #fff;
    --hover-color: #e0e0e0;
    --link-color: dodgerblue;
    --nav-border-color: #bbbbdd;
  }
}

 @media only screen and (max-device-width: 480px) {
  article, .container {
    width: 100%;
  }
  html {
    font-size: 13px;
  }
}

 * {
  color: var(--fg-color);
  text-decoration: none;
}
 a {
  color: var(--link-color);
}

 html {
  font-size: 20px;
  font-family: "Charter", "Georgia", "Times New Roman", serif;
}

 body {
  background-color: var(--bg-color);
  line-height: 1.3;
}
 article, .container {
  max-width: 800px;
  margin: auto;
}
 h1,h2,h3,h4 {
  font-family: arial, sans;
}
 h2 {
  text-align: center;
  margin-bottom: 1em;
}
 h3 {
  font-family: arial, sans;
  margin: 1.3em 0 0.9em;
}
 b {
  font-family: arial, sans;
  font-weight: normal;
  font-size: 0.8em;
}
 pre, p {
  margin: 0.9em 0px 0.9em;
}
 pre, code {
  background-color: var(--bg-color);
  line-height: normal;
  overflow: auto;
  font-size: 0.8em;
}
 pre {
  padding: 0.5em 0.5em;
  border-radius: 4px;
}
 nav ul {
  padding-left: 0;
  border-radius: 4px;
  list-style: none;
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  font-size: 0.8em;
  background-color: var(--bg-color);
  border: 1px solid var(--nav-border-color);
  overflow: scroll;
}
 nav li:first-child {
  border-left: none;
}
 nav li {
  border-right: 1px solid var(--nav-border-color);
  border-left: 1px solid var(--fg-color);
}
 nav a {
  padding: 0.4em 1em;
  display: inline-block;
  text-decoration: none;
  font-family: arial, sans;
}
 nav a:hover {
  background-color: var(--hover-color);
}
 nav a:link {
  color: var(--link-color);
}
 nav a:visited {
  color: var(--link-color);
}
 nav a.here {
  background-color: var(--hover-color);
}

 img {
  max-width: 100%;
  height: auto;
  width: auto;
  margin-left: auto;
  margin-right: auto;
  display: block;
}