#app {
  position: relative;
}

.xue {
  position: absolute;
  display: inline-block;
  /* opacity: .7; */
  outline: none;
  border: none;
  animation: xuehua 5s infinite linear;
}

.xue:hover {
  cursor: pointer;
  animation-play-state: paused;
  opacity: 1;
}

@keyframes xuehua {
  from {
    opacity: 1;
    transform: translate(0, 0) rotate(0deg);
  }
  to {
    opacity: 0;
    transform: translate(0, 700px) rotateZ(720deg) rotateY(720deg) scale(1.5);
  }
}