Placeholders
Use loading placeholders for your components or pages to indicate something may still be loading.
Example
In the example below, we take a typical card component and recreate it with placeholders applied to create a “loading card”. Size and proportions are the same between the two.
Card title
Some quick example text to build on the card title and make up the bulk of the card's content.
Go somewhere<div class="card"> <img src="..." class="card-img-top" alt="..."> <div class="card-body"> <h5 class="card-title">Card title</h5> <p class="card-text">Some quick example text to build on the card title and make up the bulk of the card's content.</p> <a href="#" class="btn btn-primary">Go somewhere</a> </div></div><div class="card" aria-hidden="true"> <img src="..." class="card-img-top" alt="..."> <div class="card-body"> <h5 class="card-title placeholder-glow"> <span class="placeholder col-6"></span> </h5> <p class="card-text placeholder-glow"> <span class="placeholder col-7"></span> <span class="placeholder col-4"></span> <span class="placeholder col-4"></span> <span class="placeholder col-6"></span> <span class="placeholder col-8"></span> </p> <a href="#" tabindex="-1" class="btn btn-primary disabled placeholder col-6"></a> </div></div>Color
By default, the placeholder uses currentColor. This can be overridden with a custom color or utility class.
<span class="placeholder col-12 bg-primary"></span>Sizing
The size of .placeholders are based on the typographic style of the parent element. Customize them with sizing modifiers: .placeholder-lg, .placeholder-sm, or .placeholder-xs.
<span class="placeholder col-12"></span>Animation
Animate placeholders with .placeholder-glow or .placeholder-wave to better convey the perception of something being actively loaded.
<p class="placeholder-glow"> <span class="placeholder col-12"></span></p><p class="placeholder-wave"> <span class="placeholder col-12"></span></p> 
