转换（旋转）transform

div
{
transform:rotate(180deg);
-ms-transform:rotate(180deg);     /* IE 9 */
-moz-transform:rotate(180deg);     /* Firefox */
-webkit-transform:rotate(180deg); /* Safari 和 Chrome */
-o-transform:rotate(180deg);     /* Opera */
}

@-webkit-keyframes spin {  
  from { -webkit-transform: rotate(0deg); }  
  to { -webkit-transform: rotate(360deg); }  
}  

@-moz-keyframes spin {  
  from { -moz-transform: rotate(0deg); }  
  to { -moz-transform: rotate(360deg); }  
}  

@-ms-keyframes spin {  
  from { -ms-transform: rotate(0deg); }  
  to { -ms-transform: rotate(360deg); }  
} 

@-o-keyframes spin {  
  from { -o-transform: rotate(0deg); }  
  to { -o-transform: rotate(360deg); }  
}