span.green-lights {
  animation: lights-g 10s infinite;
  transition: text-shadow 0.1s;
  border-radius: 30px;
}
span.blue-lights {
  animation: lights-b 10s infinite;
  transition: text-shadow 0.1s;
  border-radius: 30px;
}
span.red-lights {
  animation: lights-r 10s infinite;
  transition: text-shadow 0.1s;
}
span.yellow-lights {
  animation: lights-y 10s infinite;
  transition: text-shadow 0.1s;
}
span.white-lights {
  animation: lights-w 10s infinite;
  transition: text-shadow 0.1s;
}
@keyframes lights-b {
  0% { background-color: #000;}
  60% {background-color: #0049ff5c; text-shadow: 0 0 0px #000}
  90% {background-color: #000; text-shadow: 0 0 20px #000}
}
@keyframes lights-w {
  0% { text-shadow: 0 0 0px #000}
  30% { text-shadow: 0 0 15px #fff}
  70% { text-shadow: 0 0 20px #fff}
  100% { text-shadow: 0 0 30px #000}
}
@keyframes lights-g {
  0% { text-shadow: 0 0 0px #000}
  60% {background-color: green; text-shadow: 0 0 0px #000}
  90% {background-color: #000; text-shadow: 0 0 20px #000}
}
@keyframes lights-r {
  0% { text-shadow: 0 0 0px #000}
  30% { text-shadow: 0 0 15px red}
  70% { text-shadow: 0 0 20px red}
  100% { text-shadow: 0 0 30px #000}
}
@keyframes lights-y {
  0% { text-shadow: 0 0 0px #000}
  30% { text-shadow: 0 0 15px yellow}
  70% { text-shadow: 0 0 20px yellow}
  100% { text-shadow: 0 0 30px #000}
}