.scan-lines {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 9999;
  background: 
    repeating-linear-gradient(
      0deg,
      rgba(0, 255, 255, 0.05) 0px,
      rgba(0, 255, 255, 0.05) 1px,
      transparent 1px,
      transparent 3px
    ),
    linear-gradient(
      to bottom,
      transparent 0%,
      rgba(0, 255, 255, 0.1) 50%,
      transparent 100%
    );
  
  background-size: 100% 3px, 100% 100px;
  animation: crt-scan 2s linear infinite;
}

@keyframes crt-scan {
  0% { background-position: 0 0, 0 0; }
  100% { background-position: 0 0, 0 100px; }
}