Exemple de rollover css

img.card {
 position:absolute;
 border:solid thin black;
}
img.front:hover {
 z-index : 6 !important;
}

<img class="card front" style="left:10px; top:10px; z-index:1;" src="images/pokerAh.png" alt="" />
<img class="card front" style="left:42px; top:10px; z-index:2;" src="images/pokerKh.png" alt="" />
...

Illustration