CSS3 3D 四面正方形（animation，transform-style）demo效果

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .box {
      width: 250px;
      height: 250px;
      border: 1px dashed red;
      margin: 100px auto;
      position: relative;
      border-radius: 50%;

      /* 用于调试查看3D样式 */
      /* transform: rotateX(30deg) rotateY(-30deg); */

      /* 让子盒子保存3D效果 */
      transform-style: preserve-3d;

      /* 添加动画 */
      animation: gun 8s linear infinite;
    }
    .box>div {
      width: 100%;
      height: 100%;
      position: absolute;
      text-align: center;
      line-height: 250px;
      font-size: 60px;
      color: #daa520;
    }
    .left {
      background-color: rgba(255, 0, 0, 0.3);
      /* 变换旋转中心 */
      transform-origin: left;
      transform: rotateY(90deg) translateX(-125px);
    }
    .right {
      background-color: rgba(0, 0, 255, 0.3);
      /* 变换旋转中心 */
      transform-origin: right;
      transform: rotateY(90deg) translateX(125px);
    }
    .forward {
      background-color: rgba(255, 255, 0, 0.3);
      transform: translateZ(125px);
    }
    .back {
      background-color: rgba(0, 255, 255, 0.3);
      transform: translateZ(-125px);
    }
    .up {
      background-color: rgba(255, 0, 255, 0.3);
      transform: rotateX(90deg) translateZ(125px);
    }
    .down {
      background-color: rgba(0, 255, 0, 0.3);
      transform: rotateX(90deg) translateZ(-125px);
    }

    @keyframes gun {
      0% {
        transform: rotateX(0deg) rotateY(0deg);
      }
      100% {
        transform: rotateX(360deg) rotateY(360deg);
      }
    }
  </style>
</head>
<body>
  <div class="box">
    <div class="up">上</div>
    <div class="down">下</div>
    <div class="left">左</div>
    <div class="right">右</div>
    <div class="forward">前</div>
    <div class="back">后</div>
  </div>
</body>
</html>
demo 效果