* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.row {
    display: flex;
}

.col {
    flex: 1;
    margin: 0 0.5rem;
}

@media screen and (max-width: 640px) {
    .row {
        flex-direction: column;
    }

    .col {
        margin: 0.5rem 0;
        width: 100% !important;
    }
}

.hidden {
    display: none;
}