Untitled

<style type="text/css">
    .card {
         position: relative;
        display: inline-block;
        margin-top: 10px;
    }
    .card .img-top {
        display: none;
        position: absolute;
        top: 0;
        left: 0;
        z-index: 99;
    }
    .card:hover .img-top {
        display: inline;
    }
</style>
<body>
    <div class="card">
    	<img src="https://my.mixtape.moe/gyftra.jpg" alt="Back">
        <img src="https://my.mixtape.moe/yrbwzl.jpg" class="img-top" alt="Front">
    </div>
</body>