body{
  padding: 0;
  margin: 0;
}
main{
  display: flex;
  height: 100vh;
}

@keyframes hi{
  from{
    flex-grow: 0;
  }
}

@keyframes hello{
  to{
       flex-grow: 0;
  }
}

main>div{
  animation: hi 0.3s ease 0s both;
  display: flex;
  flex-direction: column;
  border-radius: 1em;
  overflow: hidden;
}

main div>div{
  border-radius: 3em 3em 50em 50em;
  animation: hi 0.3s ease 0s both;
  display: flex;
  background: currentColor;
}

.move{
   animation: hello 0.3s ease 0s both;
}