.snowflake {
  position: fixed;
  top: -10px;
  color: white;
  font-size: 1em;
  pointer-events: none;
  animation: snow 10s linear infinite;
  z-index: 9999;
}

@keyframes snow {
  0% { transform: translateY(0); }
  100% { transform: translateY(100vh); }
}