body {
   font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
   background-color: #ffffff;
   color: #212121;
   max-width: 800px;
   margin: 40px auto;
   padding: 0 20px;
   line-height: 1.7;
   text-align: center;
}

h1 {
   font-size: 2.5em;
   margin-bottom: 0.2em;
}

nav {
   margin: 20px 0 40px;
   border-bottom: 1px solid #eee;
   padding-bottom: 10px;
}

nav a {
   margin: 0 15px;
   color: #0d47a1;
   text-decoration: none;
   font-weight: 500;
}

nav a.active {
   border-bottom: 2px solid #0d47a1;
}

nav a:hover {
   text-decoration: underline;
}

section {
   text-align: left;
}

header a {
    margin: 0 15px;
    color: #0d47a1;
    text-decoration: none;
}