如何在div中从包装器底部向上飞行

<div class="wrapper">
  <div class="fly"></div>
</div>

.wrapper {
  position: relative;
  height: 400px;
  width: 400px;
  border: 1px solid #000;
  overflow: hidden;
}

.fly {
  position: absolute;
  bottom: 0;
  height: 50px;
  width: 50px;
  background-color: red;
}

@keyframes fly-animation {
  0% {
    bottom: 0;
  }
  100% {
    bottom: 100%;
  }
}

.fly {
  animation: fly-animation 3s infinite;
}