@keyframes twinkle {
  0%, 100% { opacity: 0.3; transform: scale(1); }
  50%       { opacity: 1;   transform: scale(1.8); }
}

@keyframes scrollPulse {
  0%   { top: -100%; opacity: 0; }
  12%  { opacity: 1; }
  88%  { opacity: 1; }
  100% { top: 100%;  opacity: 0; }
}