* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  html {
    color-scheme: light dark;
    background-color: #fff;
    color: #161616;
  }
  @media (prefers-color-scheme: dark) {
    html {
      background-color: #000;
      color: #fff;
    }
  }
  
  /* centered plain links */
  header {
    position: sticky;
    top: 0;
    z-index: 10;
    padding: 14px 18px 6px;
    background: inherit;
    text-align: center;
    font: 14px / 1.4 system-ui;
    opacity: 0.8;
    user-select: none;
  }
  
  header a {
    color: inherit;
    text-decoration: none;
    margin: 0 10px;
    text-underline-offset: 6px;
  }
  
  header a:hover {
    text-decoration: underline;
  }
  
  article {
    outline: none;
    padding: 12px max(18px, calc(50vw - 400px)) 18px;
    width: 100%;
    min-height: 100vh;
    font: 18px / 1.5 system-ui;
    tab-size: 4;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    white-space: pre-wrap;
    text-wrap-style: stable;
    overflow-wrap: break-word;
  }