.btn-shine
  position: absolute
  top: 50%
  left: 50%
  transform: translate(-50%,-50%)
  padding: 12px 48px
  color: #ffffff
  background: linear-gradient(to right, #4d4d4d 0, white 10%, #4d4d4d 20%)
  background-position: 0
  -webkit-background-clip: text
  -webkit-text-fill-color: transparent
  animation: shine 3s infinite linear
  animation-fill-mode: forwards
  -webkit-text-size-adjust: none
  font-weight: 600
  font-size: 16px
  text-decoration: none
  white-space: nowrap
    
@keyframes shine
  0%
    background-position: 0
  60%
    background-position: 180px
  100%
    background-position: 180px