html部分
<div class="box"><div class="div"></div></div>
css部分
.box::after {content: '';width: 200%;height: 200%;background: linear-gradient(to bottom, #ff0059, #1e00ff, #00ff2f, #fff);animation: rotate linear 8s infinite;position: absolute;z-index: -11;transform: rotate(0deg);margin-left: -15px;left: -50%;top: -50%;}.box {width: 200px;height: 200px;margin-left: 200px;position: relative;margin-top: 100px;overflow: hidden;}.div {position: absolute;top: 2px;left: 2px;bottom: 2px;right: 2px;background-color: #fff;z-index: 999999;}@keyframes rotate {0% {transform: rotate(0deg);}50% {transform: rotate(180deg);}100% {transform: rotate(359deg);}}
