To nest your content with the default grid, add a new .row
and set of .col-sm-*
columns within an existing .col-sm-*
column. Nested rows should include a set of columns that add up to 12 or fewer (it is not required that you use all 12 available columns).
<div class="row">
<div class="col-sm-9">
Level 1: .col-sm-9
<div class="row">
<div class="col-xs-8 col-sm-6">
Level 2: .col-xs-8 .col-sm-6
</div>
<div class="col-xs-4 col-sm-6">
Level 2: .col-xs-4 .col-sm-6
</div>
</div>
</div>
</div>