<div class="shape-ex4">滑鼠移動至此查看效果</div>
.shape-ex4{
    font-size: 18px;
    display: inline-block;
    vertical-align: middle;
    position: relative;
    transition: all .3s linear;
}
.shape-ex4:hover{
       color: #fff;
    background-color: #000
}

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