函数式编程
<!-- Stack the columns on mobile by making one full-width and the other half-width --><div class="row"><div class="col-xs-12 col-md-8">.col-xs-12 .col-md-8</div><div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div></div><!-- Columns start at 50% wide on mobile and bump up to 33.3% wide on desktop --><div class="row"><div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div><div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div><div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div></div><!-- Columns are always 50% wide, on mobile and desktop --><div class="row"><div class="col-xs-6">.col-xs-6</div><div class="col-xs-6">.col-xs-6</div></div>这样就可以了。