body {
    background-color:#9999aa;
}

header, section, aside {
    max-width:80em;
    margin-left:auto;
    margin-right:auto;
    background-color:#ffffff;
    border-radius:3px;
    padding:20px;
}

pre {
    margin: 20px;
    padding: 10px;
    background-color: #222233;
    border-radius: 5px;
    color: #ffffff;
    font-family: monospace;
}

section, aside {
    margin-top:10px;
}

aside {
    font-style: italic;
}

h3 {
    margin:inherit;
    margin-bottom:10px;
}