Green wave animated silhouette

<div></div>

div {
  mask-image: url("img/wave.webp");
  mask-size: 100% 100%;
  mask-repeat: no-repeat;

  /* need to set a background */
  background-color: green;

  height: 94%;
  max-width: 30rem;
  aspect-ratio: 1 / 1;
}

body {
  height: 100dvh;
  margin: 0;

  display: grid;
  place-items: center;
}