需求：一个div围绕另一个div旋转
首先让要旋转的div本身先位移，再进行旋转；元素 translate 移动之后，并不修改元素本身的变换源点；
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<head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta http-equiv="X-UA-Compatible" content="ie=edge"><title>Document</title><style>/* 旋转条件：要旋转的div在旋转之前先位移；要旋转的div需要设置绝对定位 */#box {width: 400px;height: 400px;border: 1px solid black;padding: 50px;margin: 150px auto;position: relative;}#div1 {width: 100px;height: 100px;background: red;position: absolute;top: 200px;left: 200px;border-radius: 50%;}#div2 {width: 100px;height: 100px;background: blue;position: absolute;top: 200px;left: 200px;transition: 3s ease-in;transform: rotate(0deg) translateX(100px);}#box:hover #div2 {transform: rotate(360deg) translateX(100px);}</style>
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<body><div id="box"><div id="div1"></div><div id="div2"></div></div>
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