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 .third-party { position: relative; // 为了兼容firefox必须要变成block或inline-block display: inline-block; width: 48px; height: 48px; margin: { left: 6%; right: 6%; } &:hover { i { &::after { transform: scale(1); } } } span { // position: relative是为了兼容firefox和IE position: relative; display: block; width: 48px; height: 48px; background-size: 30px; background-position: center; background-repeat: no-repeat; } i { position: absolute; top: 0; left: 0; width: 48px; height: 48px; &::before { content: ''; border-radius: 50%; position: absolute; top: 0; left: 0; right: 0; bottom: 0; } &::after { content: ''; transition: all .3s; border-radius: 50%; position: absolute; top: 0; left: 0; right: 0; bottom: 0; transform: scale(0); } } &.third-party-weixin { span { background-image: url(../images/login/weixin-64.png); } i { &::before { background-color: #20a839; } &::after { background-color: #30cc54; } } } }