<div class="container">
    <h4>Placeholders example - animation</h4>
    <!--placeholder-glow-->
    <p class="placeholder-glow">
        <span class="placeholder col-10"></span>
    </p>
    <!--no animation-->
    <p><span class="placeholder col-10 "></span></p>
    <!--placeholder-wave-->
    <p class="placeholder-wave">
        <span class="placeholder col-10"></span>
    </p>
</div>