css实现毛毛虫爬行动作

<div class='container'>
  <div class='hide left'></div>
  <div class='hide right'></div>
  <div class='hide bottom'></div>
  <div class='circle-container'>
    <div class='circle'></div>
  </div>
</div>

 <style>
body {
  background-color: #1B6CB2;
  margin: 0;
}
.container {
  position: absolute;
  width: 600px;
  height: 400px;
  overflow: hidden;
  : 50%;
  left: 60%;
  transform: translate(-50%, -50%);
}
.hide {
  height: 100%;
  width: 150px;
  background: #1B6CB2;
  position: absolute;
  z-index: 2;
}
.hide.left {
  left: 0;
}
.hide.right {
  right: 0;
}
.hide.bottom {
  bottom: 0;
  width: 100%;
  height: 50%;
}
.circle {
  position: absolute;
  height: 75px;
  width: 150px;
  border: 3px solid white;
  border-radius: 50%/100% 100% 0 0;
  border-bottom: none;
  : 40%;
  left: 50%;
  transform-origin: 0% 50%;
  transform: translate(-50%, -50%);
  animation: magic 1.8s ease infinite;
}
@keyframes magic {
  0% {
    transform: rotate(-170deg) translate(-50%, -50%);
  }
  50% {
    transform: rotate(0deg) translate(-50%, -50%);
  }
  100% {
    transform: rotate(180deg) translate(-50%, -50%);
  }
}
.circle-container {
  position: absolute;
  height: 75px;
  width: 150px;
  : 40%;
  left: 50%;
  transform-origin: 0% 50%;
  transform: translate(-50%, -50%);
  animation: power 1.8s ease-out infinite;
}
@keyframes power {
  0% {
    margin-left: 20px;
  }
  50% {
    margin-left: -55px;
  }
  99.9% {
    margin-left: -130px;
  }
  100% {
    margin-left: 20px;
  }
}
  </style>