#page_not_found {
    text-align: center;
}
#page_not_found h2 {
    position: relative;
    font-size: 2.25rem;
}
.four-o-four {
    display: block;
    font-size: 2.5em;
    color: #111;
    max-width: 300px;
    width: 100%;
    height: auto;
    margin: 0 auto 30px;
}