bootstrap breadcrumb accessibility

1<nav aria-label="breadcrumb">
2  <ol class="breadcrumb">
3    <li class="breadcrumb-item"><a href="#">Home</a></li>
4    <li class="breadcrumb-item"><a href="#">Library</a></li>
5    <li class="breadcrumb-item active">Data</li>
6  </ol>
7</nav>

1Indicate the current page’s location within a navigational hierarchy that 
2automatically adds separators via CSS.
3<nav aria-label="breadcrumb">
4  <ol class="breadcrumb">
5    <li class="breadcrumb-item active" aria-current="page">Home</li>
6  </ol>
7</nav>
8
9<nav aria-label="breadcrumb">
10  <ol class="breadcrumb">
11    <li class="breadcrumb-item"><a href="#">Home</a></li>
12    <li class="breadcrumb-item active" aria-current="page">Library</li>
13  </ol>
14</nav>
15
16<nav aria-label="breadcrumb">
17  <ol class="breadcrumb">
18    <li class="breadcrumb-item"><a href="#">Home</a></li>
19    <li class="breadcrumb-item"><a href="#">Library</a></li>
20    <li class="breadcrumb-item active" aria-current="page">Data</li>
21  </ol>
22</nav>
23

1Since breadcrumbs provide a navigation, it’s a good idea to add a meaningful 
2label such as aria-label="breadcrumb" to describe the type of navigation
3provided in the <nav> element, as well as applying an aria-current="page"
4to the last item of the set to indicate that it represents the current page.