movim/themes/material/css/block.css

.flex {
    display: flex;
    flex-flow: row wrap;
}

.flex .block {
    flex: 1 50%;
}

.flex .block.large {
    flex: 1 100%;
}

.flex.card {
    padding: 0;
}

.flex.card .block {
    margin: 1rem;
    flex: 1 calc(50% - 2rem);
    min-height: 12rem;
    padding-top: 1.5rem;
    padding-bottom: 1.5rem;
}

.flex.card .block:not(.condensed) {
    padding-top: 3rem;
}

@media screen and (max-width: 1024px) {
    .flex.card .block,
    .flex .block {
        margin-bottom: 0;
        flex: 1 100%;
    }
}