.hover in bootstrap code example
Example 1: bootstrap 4 class for hover
<div class="view overlay">
<img src="https://mdbootstrap.com/img/Photos/Horizontal/City/6-col/img%20(3).jpg" class="img-fluid " alt="">
<div class="mask rgba-red-strong">
</div>
</div>
Example 2: hover option bootstrap
<div class="dropdown">
<button class="btn btn-default dropdown-toggle" type="button" data-toggle="dropdown" data-hover="dropdown">
Dropdown <span class="caret"></span>
</button>
<ul class="dropdown-menu">
<li><a href="#">Action</a></li>
<li><a href="#">Another action</a></li>
<li class="dropdown">
<a href="#">One more dropdown</a>
<ul class="dropdown-menu">
<li><a href="#">Action</a></li>
<li><a href="#">Another action</a></li>
<li class="dropdown">
<a href="#">One more dropdown</a>
<ul class="dropdown-menu">
...
</ul>
</li>
<li><a href="#">Something else here</a></li>
<li><a href="#">Separated link</a></li>
</ul>
</li>
<li><a href="#">Something else here</a></li>
<li><a href="#">Separated link</a></li>
</ul>
</div>