.is-loading { /* ??? */
    display: flex;
    height: 100%;
}

.is-loading > * {
    display: none!important;
}

.is-loading::after {
    content: "";
    display: flex;
    width: 50px;
    height: 50px;
    margin: auto;
    border-radius: 50%;
    border: 5px solid #6c7179;
    border-color: #6c7179 transparent #6c7179 transparent;
    animation: is-loading 2s linear infinite;
}

@keyframes is-loading {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

div.blockContainer {
    min-height: 600px; /* Give the initial, non lazy loaded blocks some height, to prevent them all loading by default initially */
}