header {
    height: 50px;
    background: #FFF;
    box-shadow: 0 0 12px rgba(0, 0, 0, .1);
    z-index: 9999 !important;
    box-sizing: border-box;
}

@media (max-width: 577px) {
    header {
        height: 100px;
    }
}

.central {
    display: grid;
    place-content: center;
    place-items: center;
}