b {
  position: relative;
  text-align: center;
  font-size: 10vmin;
  text-transform: uppercase;
  line-height: .10;
  background: linear-gradient(100deg, #000, #fff, #000);
  background-size: 80% 100%;
  background-repeat: no-repeat;
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: shine 5s linear infinite;
}

@keyframes shine {
  0% {
    background-position-x: -500%;
  }
  
  100% {
    background-position-x: 500%;
  }
}