.slide {
  display: none;
  animation: fadeIn 1s ease-in;
}

button:hover {
  background: #000;
  color: #fff;
  transition: 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}