HTML<div id="containerEx3"><div class="ex3"> <img alt="img0" src="http: ../imagen0.jpg"width="190" height="170" /> <img alt="img1" src="http: ../imagen1.jpg" width="190" height="170"/> <img alt="img2" src="http: ../imagen2.jpg" width="190" height="170"/> <img alt="img3" src="http: ../imagen3.jpg" width="190" height="170"/> </div></div>

CSS<style type="text/css"><!-- 
#containerEx3 {width: 800px;
margin: 0 auto;
}
.ex3 img {
margin: 20px;
border: 2px dotted #fff; 
border-radius: 1em;
-webkit-box-shadow: 4px 4px 4px rgba(0,0,0,0.2);
-moz-box-shadow: 4px 4px 4px rgba(0,0,0,0.2);
box-shadow: 4px 4px 4px rgba(0,0,0,0.2);
-webkit-transition: all 0.5s ease-out;
-moz-transition: all 0.5s ease;
-ms-transition: all 0.5s ease;
}
.ex3 img:hover {
-webkit-transform: rotate(-7deg);
-moz-transform: rotate(-7deg);
-ms-transform: rotate(-7deg);
transform: rotate(-7deg);
}
--></style>