.alert-enter {
  opacity: 0.01;
  transition: opacity 1s ease-in;
}

.alert-enter.alert-enter-active {
  opacity: 1;
}

.alert-leave {
  opacity: 1;
  transition: opacity 1s ease-in;
}

.alert-leave.alert-leave-active {
  opacity: 0.01;
}