.root {
    display: grid;
    grid-template-columns: 1fr;
}

.mobileChat {
    display: block;
    position: absolute;
    background-color: white;
    top: 0px;
    width: 100%;
    height: calc(50vh - var(--header-h));
}

.leftCol {
    display: grid;
    // -64px, which is the header
    grid-template-rows: 50vh calc(50vh - var(--header-h));
}
.lowerRow {
    position: relative;
    display: grid;
    grid-template-rows: 1fr var(--header-h);
}

@media (min-width: 768px) {
    .mobileChat {
        display: none;
    }
    .root[data-columns='2'] {
        grid-template-columns: 1fr var(--chat-w);
    }
}