Bootstrap wells can be used to create headings or emphasize content. The well class adds a rounded border around an element with a light gray background and some padding, as shown in this example.
The wells come in different sizes, including small, normal and large.
Let's take a look at the code.
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<div class="well well-sm">Small Well</div>
<div class="well">Normal Well</div>
<div class="well well-lg">Large Well</div>
Here we can see three divs. Each
<div> has a different class. The first
<div> has the well and well-sm class.
<div> uses the well class, with no size specified. This will create the default normal well size.
Lastly we have a
<div> with the well and well-lg class. This is used to create a large well.