更新2018 ...

card取代了well.

引导程序4

<div class="card card-body bg-light">
     Well
</div>

或 ，作为两个DIV ...

or, as two DIVs...

<div class="card bg-light">
    <div class="card-body">
        ...
    </div>
</div>

(注意:在Bootstrap 4 Alpha中，它们被称为card-block而不是card-body和bg-faded而不是bg-light)

(Note: in Bootstrap 4 Alpha, these were known as card-block instead of card-body and bg-faded instead of bg-light)

http://codeply.com/go/rW2d0qxx08