Animação CSS não exibe nenhum

/* css animation does not support display none, 
one hack is to just set height:0px;width:0px; on the animation*/
@keyframes JumpOut {                                                          
  0%   { top:10px; }                                                                 
  100% { top:-1020px; height:0px;width:0px;}                                                       
}   
Friendly Hawk