animation button continuous

by Roberto Apasajja

HTML

<a class="btn01" href="#">Button link</a>

CSS

body {
  padding: 2em;
}

.btn01 {
  background: pink;
  padding: 9px 1em;
  text-decoration: none;
  animation: abcde 1.5s infinite linear;
}

@keyframes abcde {
  from {
    box-shadow: 0 0 0 0px grey;
  }
  to {
    box-shadow: 0 0 0 20px transparent;
  }
}