.main {
    height: 100vh;
    box-sizing: border-box;
    overflow: hidden;
}

#header {
    height: 10vh !important;
    box-sizing: border-box;
}

.parent-404 {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 77vh;
    box-sizing: border-box;
}

@media (max-width: 991px) {
    .main {
        height: auto;
    }
}