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<head><meta charset&#61;"UTF-8"><title>矩形-圆动画转换动画效果title><style>div{width:200px;height:200px;background-color:blue;}transition:{border-radius:2s,width:2s,height:2s,background-color:2s;}div:hover{border-radius:100px;background-color:red;}#d1{transition-timing-function:linear;}style>
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