.client-container{
position: relative;
display: inline-block;
}
.client-content {
display: none;
position: absolute;
background-color: #fff;
min-width: 160px;
box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
z-index: 1;
top:0;
transition:337ms ease-in-out;
}
.client-container:hover .client-content {
display: block;
}
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.2.1/css/bootstrap.min.css" integrity="sha384-GJzZqFGwb1QTTN6wy59ffF1BuGJpLSa9DkKMp0DgiMDm4iYMj70gZWKYbI706tWS" crossorigin="anonymous">
<div class="container">
<div class="row">
<div class="col-12 mt-5">
<h2 class="text-center">Our Clients</h2>
</div>
</div>
<div class="row">
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/1.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/1.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/2.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/2.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/4.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/4.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
</div>
<div class="row">
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/5.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/5.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/4.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/4.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/2.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/2.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
</div>
<div class="row">
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/1.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/1.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/2.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/2.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
<div class="col-lg-3 text-center client-container">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="80%" height="auto">
<div class="client-content p-4">
<img src="https://www.gstatic.com/webp/gallery/3.sm.jpg" width="100%" height="auto">
<p style="padding-top: 10px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean mattis dui vitae placerat vehicula. Aliquam ante lectus, suscipit non eros eu, mattis tempus turpis. Curabitur iaculis hendrerit dolor quis ultricies. Donec dignissim rutrum lectus
et dignissim. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Morbi.</p>
<a class="btn btn-custom">Read More</a>
</div>
</div>
</div>
<div class="row">
<div class="col-lg-12 text-center text-center">
<button class="btn btn-warning">All Clients</button>
</div>
</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
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