.title-404 {
    font-size: 5rem;
    font-weight: 600;
    -webkit-user-select: none;
    -webkit-user-drag: none;
}

.message {
    font-size: 2.5rem;
    font-weight: 700;
}

.back-btn {
    font-weight: 600;
}

.back-btn, .back-btn:link, .back-btn:visited, .back-btn:active {
    text-decoration: none;
    color: #1f4f6f;
}

.back-btn:hover {
    color: #2e6898;
    font-weight: 800;
}

@media (max-width: 450px) {
    .title-404 {
        font-size: 2.5rem;
        font-weight: 600;
    }

    .message {
        font-size: 1.25rem;
        font-weight: 700;
    }
}