<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>test</title>
</head>
<body>
    <div class="box">
      page body
      <div class="img"></div>
    </div>
</body>
</html>
@keyframes leftIn {
  0% {
    right: -100px;
  }

  100% {
    right: 0;
  }
}
@keyframes handShake {
  0% {
    transform: rotate(0deg);
  }

  14.3% {
    transform: rotate(-9deg);
  }

  25.7% {
    transform: rotate(-1deg);
  }

  34.3% {
    transform: rotate(-10deg);
  }

  42.9% {
    transform: rotate(0deg);
  }

  100% {
    transform: rotate(0deg);
  }
}

.box {
  position: relative;
  top: 40;
  left: 0px;
  width: 300px;
  height: 200px;
  border: 1px solid red;
}

.img {
  position: absolute;
  right: -20px;
  bottom: 100px;
  width: 0;
  height: 0;
  height: auto;
  border-top: 50px solid transparent;
  border-bottom: 50px solid transparent;
  border-left: 100px solid red;
  transform-origin: 100px 50px;
  animation-name: leftIn, handShake;
  animation-duration: .8s, 1.6s;
  animation-timing-function: ease-in-out, ease-in-out;
  animation-delay: 1s, 2s;
  animation-iteration-count: 1, 100;
  animation-fill-mode: both, both;
}

External CSS

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External JavaScript

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