.galaxy {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: radial-gradient(circle, #1a001f 0%, #2a0635 100%);
  overflow: hidden;
  z-index: -2;
}

.stars {
  background: url('https://www.transparenttextures.com/patterns/stardust.png') repeat;
  opacity: 0.8;
  animation: moveStars 30s linear infinite;
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  z-index: -1;
}

@keyframes moveStars {
  from { transform: translateY(0); }
  to { transform: translateY(-100%); }
}