<div class="loading_container">
  <div class="loading">
  </div>
  <h3>loading...</h3>

</div>
:root {
  --animation-speed: 2s;
  --primary-color: #fff;
  --secondary-color: #000;
  --background-color: #212121;
  --text-color: #fff;
  --font: sans-serif;
}

* {
  margin: 0;
  padding: 0;
}

body {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  background: var(--background-color);
  font-family: var(--font);
}
.loading_container {
  width: 200px;
  height: 200px;
  position: relative;
  /*   background: greenyellow; */
  border-radius: 150px;
}

.loading {
  width: 100%;
  height: 100%;
  border-radius: 150px;
  border-right: 0.3rem solid white;
  animation: animate var(--animation-speed) linear infinite;
}

.loading_container h3 {
  color: var(--text-color);
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
}

/* Animation */

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

External CSS

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External JavaScript

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