<img class="mask" src="https://picsum.photos/id/1069/200/200">
.mask {
  -webkit-mask: radial-gradient(30px,#0000 98%,#000) 0 0;
  transition:.5s linear;
  cursor:pointer;
}
.mask:hover {
  -webkit-mask: radial-gradient(30px,#0000 98%,#000) -100px -100px;
}

body {
  background: pink;
}

External CSS

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External JavaScript

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