rounded border bootstrap 4 classes code example
Example 1: bootstrap border color
<span class="border border-primary"></span>
<span class="border border-secondary"></span>
<span class="border border-success"></span>
<span class="border border-danger"></span>
<span class="border border-warning"></span>
<span class="border border-info"></span>
<span class="border border-light"></span>
<span class="border border-dark"></span>
<span class="border border-white"></span>
Example 2: outline text bootstrap
<span class="border">Text</span>
<span class="border-top">Text</span>
<span class="border-right">Text</span>
<span class="border-bottom">Text</span>
<span class="border-left">Text</span>