Here is my custom construction:
<div style="display: table;">
<div style="display: table-cell; width: 50px; background-color: red;">a</div>
<div style="display: table-cell; width: 100%; background-color: green;">...</div>
<div style="display: table-cell; width: 50px; background-color: red;">a</div>
</div>
Despite assigning a 50px width to the edge columns, they do not seem to be taking effect as expected