body {
 margin-left: 4em;
 margin-right: 4em;
}

h1 {
 margin-left: -1em;
 margin-right: -1em;
}

section h1 {
 color: white;
 background-color: black;
 padding: 0.5em 1em 0.5em 1em;
}

pre {
 margin-bottom: 0;
}