Expanding a div to take up the space in a row

<div class="row">
    <div class="contained">
        <span>Some Text</span>
    </div>
    <div class="expanded">
        <span>Some more text that should take up all the remaining space.</span>
    </div>
</div>
<div class="table">
    <div class="row">
        <div class="contained">
            <span>Some Text</span>
        </div>
        <div class="expanded">
            <span>Some more text that should take up all the remaining space.</span>
        </div>
    </div>
</div>
.table {
    display: table;
    width: 100%;
}

.row {
    display: table-row;
}

.contained {
    display: table-cell;
    width: 1px;
    white-space: nowrap;
}

.expanded {
    display: table-cell;
}