<div class="radius">
  <div class="content"></div>
</div>
@import url("https://fonts.googleapis.com/css2?family=Exo:wght@600&display=swap");

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  width: 100vw;
  min-height: 100vh;
  font-family: "Exo", Arial, sans-serif;
  background-color: #557;
  color: #fff;
  display: grid;
  gap: 30px;
  place-content: center;
}

.radius {
  height: 100px;
  display: flex;
  justify-content: flex-start;
}

.radius::before,
.radius::after {
  content: "";
  width: 20px;
  background: #098fae;
}

.radius::before {
  border-radius: 20px 0 0 20px;
}

.content {
  background: #098fae;
  width: 1px;
  transform: scale3d(1, 1, 1);
  transform-origin: left;
}

.radius::after {
  border-radius: 0 20px 20px 0;
  transform: translate3d(0, 0, 0);
}

@keyframes right-animate {
  0% {
    transform: translate3d(0, 0, 0);
  }
  100% {
    transform: translate3d(80px, 0, 0);
  }
}

@keyframes center-animate {
  0% {
    transform: scale3d(1, 1, 1);
  }
  100% {
    transform: scale3d(81, 1, 1);
  }
}

.content {
  animation: center-animate 1s linear infinite alternate;
}

.radius::after {
  animation: right-animate 1s linear infinite alternate;
}

External CSS

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External JavaScript

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