.stars {
  position: fixed;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
  z-index: -1;
}

.stars .star {
  position: absolute;
  width: 2px;
  height: 2px;
  background: var(--color-white);
  border-radius: 50%;
  animation: move-stars 10s linear infinite;
  opacity: 0.8;
}

@keyframes move-stars {
  0%   { transform: translateY(calc(100 * var(--vh, 1vh))); opacity: 0.2; }
  100% { transform: translateY(calc(-10 * var(--vh, 1vh))); opacity: 1; }
}