main > ul:first-of-type{
    display: flex;/*弹性盒模型*/
    position: relative;/*相对定位*/
    width: 1903px;
    height: 120px;
    margin: 60px 0;
    /* background-color: rgb(0, 0, 0); */
}
main > ul:first-of-type > li:first-of-type{
    width: 480px;
    height: 120px;
    background:linear-gradient(90deg,cyan 0%,cyan 10%,
                            rgb(0, 194, 194) 50%,rgb(0, 93, 93) 100%)bottom right/480px 120px no-repeat;
    border-radius: 0 50% 50% 0;/*圆角*/
}
main > ul:first-of-type > li:nth-child(2){
    position: absolute;/* 绝对定位 */
    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
    z-index:1;/* 定位层级 */
    width: 1063px;
    height: 90px;
    margin: auto;
    background-color: rgb(0, 165, 165);
    font-size:50px;/*字体大小*/
    color: rgb(255, 254, 254);
    line-height:80px;/*字体垂直居中*/
    text-align:center;/*字体水平居中*/
    border-radius: 25% 25% 25% 25%/50% 50% 50% 50%;/*圆角*/
}
main > ul:first-of-type > li:last-of-type{
    width: 480px;
    height: 120px;
    background:linear-gradient(90deg,rgb(0, 93, 93) 0%,rgb(0, 194, 194) 50%,
    cyan 90%,cyan 100%)bottom right/480px 120px no-repeat;
    margin-left: 943px;
    border-radius: 50% 0 0 50%;/*圆角*/
}