dotted border in bootstrap 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: border radius bootstrap

Border-radius
Add classes to an element to easily round its corners.

<img src="..." alt="..." class="rounded">
<img src="..." alt="..." class="rounded-top">
<img src="..." alt="..." class="rounded-right">
<img src="..." alt="..." class="rounded-bottom">
<img src="..." alt="..." class="rounded-left">
<img src="..." alt="..." class="rounded-circle">
<img src="..." alt="..." class="rounded-0">

Example 3: dashed lin in css

hr {
  border:none;
  border-top:1px dashed #f00;
  color:#fff;
  background-color:#fff;
  height:1px;
  width:50%;
}