<img src="img/jiaotou.png" class="xwcms" />
.xwcms {
margin: 0 auto;
-webkit-border-radius: 110px;
border-radius: 110px;
-webkit-transition: -webkit-transform 0.2s ease-out;
-moz-transition: -moz-transform 0.2s ease-out;
-o-transition: -o-transform 0.2s ease-out;
-ms-transition: -ms-transform 0.2s ease-out;
}
.xwcms:hover {
-webkit-transform: rotateZ(180deg);
-moz-transform: rotateZ(180deg);
-o-transform: rotateZ(180deg);
-ms-transform: rotateZ(180deg);
transform: rotateZ(180deg);
}