.not-found-page .not-found-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.not-found-page .not-found-title-line { width: 100%; }
.not-found-page .not-found-card p { width: min(100%, 540px); }

@media (max-width: 600px) {
    .not-found-page .not-found-card { justify-content: center; }
}