html,
body
{
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

header
{
    height: 16rem;
    background: #111 url('./images/header.jpg') bottom center;
    background-size: cover;
    background-repeat: no-repeat;
}

nav
{
    display: flex;
    background: #111;
    position: relative;
    overflow: hidden;
}

nav:after
{
    content: "";
    display: block;
    position: absolute;
    width: 150%;
    height: 150%;
    bottom: 0;
    left: -25%;
    -webkit-box-shadow: inset 0px 1px 15px 4px #666; 
    box-shadow: inset 0px 1px 15px 4px #666;
    pointer-events: none;
}

nav a
{
    flex: 10rem auto auto;
    padding: 2rem;
    text-decoration: none;
    color: #fff;
    background: #222;
}

nav a:hover
{
    color: #fff;
    background: #444;
}

nav a.active
{
    background: #fff;
    color: #000;
    z-index: 999;
}

main
{
    max-width: 40rem;
    padding: 2rem;
}

h1,
h2
{
    margin-top: 3rem;
    margin-bottom: 0;
    color: #555;
}

p,
ul,
dl
{
    line-height: 1.4rem;
}

dl dt
{
    color: #888;
    margin-top: .4rem;
}

ul li
{
    margin-top: .4rem;
}