#page_not_found {
    text-align: center;
    padding-top: 150px;
    padding-bottom: 100px;
}
#page_not_found h2 {
    position: relative;
    font-size: 2.25rem;
    margin-top: 10px;
}
.four-o-four {
    position: absolute;
    font-size: 3em;
    color: #e8e8e8;
    top: -40px;
    left: 50%;
    transform: translateX(-50%);
    z-index: -1;
}