3.4、Bootstrap V4自学之路------内容---图文框

<span>图片的class="figure-img img-rounded"</span>
<figure class="figure">
  <img data-src="holder.js/400x300" class="figure-img img-rounded" alt='class="figure-img img-rounded"'>
  <figcaption class="figure-caption text-xs-right">'class="figure-caption text-xs-right"'</figcaption>
</figure>

拆解一下：

<figure class=figure>                                  <figure>图文框标签

-->  <img class=figure-img>                          <img>图文框的图片

-->  <figcaption class=figure-caption>           <figcaption>图文框的文字