h1 {
    counter-reset: h2counter;
    font-weight: 300;
    font-size: 3.5rem;
    margin-bottom: 1rem;
}
h2 {
    counter-reset: h3counter;
    counter-increment: h2counter;
    font-weight: 300;
    font-size: 2.5rem;
    margin-bottom: 1rem;
}
.numbered h2:before {
    content: counter(h2counter);
    margin-right: 1rem;
}
h3 {
    counter-increment: h3counter;
    font-weight: 300;
    font-size: 1.5rem;
    margin-bottom: 1rem;
}
.numbered h3:before {
    content: counter(h2counter) "." counter(h3counter);
    margin-right: 1rem;
}
pre code {
    background-color: #eee;
    display: block;
    margin-left: 1rem;
    margin-right: 1rem;
    padding: .5rem 1rem;
}