<div class="main">
  <div class="loading_box"></div>
</div>
.main{
  width: 90vw;
  margin: 0 auto;
  text-align: center;
}

.loading_box {
  width: 50px;
  height: 50px;
  margin: 10px auto;
  
  border: 10px solid #bfbfbf;
  border-radius: 10%;
  
  animation: load 3s linear infinite;
}

@keyframes load {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

External CSS

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External JavaScript

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