<div class="bronze"></div>
body{
  width:100vw;
  height:100vh;
  overflow:hidden;
  background-color:#343434;
  display:flex;
  justify-content:center;
  align-items:center;
}
div{
  width:20vw;
  height:20vw;
  border-radius:100vmax;
}
.bronze{
background: linear-gradient(45deg, #a57e65 0%, #a57e65 45%, #f3cfb8 70%, #a57e65 85%, #a57e65 90% 100%);
   background-size: 800% 400%;
  animation: gradient 5s infinite cubic-bezier(.62, .28, .23, .99) both;
}
@keyframes gradient {
  0% {
    background-position: 0% 50%;
  }

  50% {
    background-position: 100% 50%;
  }

  100% {
    background-position: 0% 50%;
  }
}

External CSS

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External JavaScript

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