* {
    box-sizing: border-box;
  }
  
  html, body {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    font-family: monospace;
  
    color: var(--fg);
    background-color: var(--bg);
  }
  
  a {
    color: var(--link);
    text-decoration: none;
    font-weight: bold;
  }
  
  a:visited {
    color: var(--link-visited);
  }

  header, footer {
    background-color: var(--bg-light);
    height: 150px;
  }
  
  footer {
    height: 50px;
  }
  
  header {
    display: flex;
    flex-direction: column;
    justify-content: space-around;
  }
  
  header > h1 {
    padding: 0;
    margin: 0;
    text-align: center;
    font-size: 4.5em;
  }

  :is(header, footer) > nav {
    display: flex;
    justify-content: center;
    gap: 20px;
    font-size: 1.5em;
  }
  
  footer > nav {
    height: 100%;
    flex-direction: column;
  }
  
  footer > nav > a {
    margin: auto;
  }

  :is(header, footer) > nav > a::before {
    content: '< ';
  }
  
  :is(header, footer) > nav > a::after {
    content: ' >';
  }
  
  :is(header, footer) > nav > a:is(:hover, .active)::before {
    content: '\00a0>';
  }
  
  :is(header, footer) > nav > a:is(:hover, .active)::after {
    content: '<\00a0';
  }
  
  :is(header, footer) > nav > a:visited {
    color: var(--link);
  }
  
  main {
    min-height: calc(100vh - 200px);
  }