Move css animation

Css : 

/* img move auto  */



img.vert-move {
    -webkit-animation: mover 1s infinite  alternate;
    animation: mover 1s infinite  alternate;
}
img.vert-move {
    -webkit-animation: mover 1s infinite  alternate;
    animation: mover 1s infinite  alternate;
}
@-webkit-keyframes mover {
    0% { transform: translateY(0); }
    100% { transform: translateY(-5px); }
}
@keyframes mover {
    0% { transform: translateY(0); }
    100% { transform: translateY(-5px); }
}

/* img move auto  */


Html : 

<center>
          <img src="assets/images/student.png" class="vert-move">
</center>