body {
  margin: 0;
  min-height: 100vh;
  background: linear-gradient(135deg,
    #ff005d,
    #ff7b00,
    #ffee00,
    #00ff85,
    #00e5ff,
    #0080ff,
    #b300ff
  );
  background-attachment: fixed;
  background-size: 400% 400%;
  animation: neonFlow 12s ease infinite;
}

@keyframes neonFlow {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}