slow animaton css

HTML

<br>
<div class="gradient-high" style="height:100px; width:100px;">

</div>

CSS

.gradient-high{

background: #EECDA3;
 animation-name: drop;
  animation-iteration-count: 1;
  animation-timing-function: ease-out;
  animation-duration: 5s;
}

@keyframes drop {
  0% {
    transform: scaleX(0vh);
  }
  100% {
    transform: scaleY(100vh);
  }
}