height: 100% for <div> inside <div> with display: table-cell

http://stackoverflow.com/questions/22220698/height-100-for-div-inside-div-with-display-table-cell

HTML

<div class="tab">
    <div class="row">
        <div class="elem">
            <div class="content">
                Content
            </div>
        </div>
        <div class="elem">
            <div class="content">
                Longer content that will need to wrap around eventually you know and don't you hate it when things don't end as you expect them octopus
            </div>
        </div>
    </div>
</div>

CSS

html, body {
    height: 100%;
}

.tab {
    display: table;
    height:100%;
    width: 200px;
}

.row {
    height: 100%;
    display: table-row;
}

.elem {
    border: 1px solid black;
    vertical-align: top;
    display: table-cell;
    height:100%;
    background: blue;
}

.content {
    height: 100%;
    background: greenyellow;
}