@keyframes zhuan
{
0 {transform:rotateZ(0deg);}
50% {transform:rotateZ(180deg);}
  100%{transform:rotateZ(360deg);}
}
@keyframes large
{
0 {transform:scale(1)}
50% {transform:scale(1.1)}
100%{transform:scale(1);}
}
@keyframes down
{
0 {top:0px;opacity:1}
50% {top:20px;opacity:0}
100% {top:0px;opacity:1}
}