Gradient Flow

.btn-gradient-flow {
  display: inline-block;
  padding: 13px 28px;
  border: none;
  border-radius: 12px;
  background: linear-gradient(270deg, #6366f1, #ec4899, #f59e0b, #6366f1);
  background-size: 600% 100%;
  color: #ffffff;
  font-family: inherit;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  animation: btn-gradient-flow-move 8s ease infinite;
}
.btn-gradient-flow:hover {
  animation-duration: 2.5s;
}
@keyframes btn-gradient-flow-move {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}