nly defining .col-sm-1-3. This rule will be inherited by .col-md and .col-lg since we don't define those, but not .col-xs because it is smaller than .col-sm.
          </p>
          <pre class="fake-code">
<!--     -->&lt;div class="frow"&gt;
<!--     -->  &lt;div class="col-sm-1-3"&gt;&lt;/div&gt;
<!--     -->  &lt;div class="col-sm-1-3"&gt;&lt;/div&gt;
<!--     -->  &lt;div class="col-sm-1-3"&gt;&lt;/div&gt;
<!--     -->&lt;/div&gt;
<!--   --></pre>
          <pre class="grid-frow-code">
<!--     --><spa