/* 顶部导航栏 */

   body .top_bar .qiehuan {
    display: flex;
    justify-content: center;
    align-items: center;
}

body .top_bar .nav {
    display: flex;
    justify-content: center;
    align-items: center;
}

body .top_bar {
    width: 100%;
    height: 100px;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 7;
    padding: 0 40px;
    box-sizing: border-box;
    overflow: hidden;
    transition: .5s;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

body .top_bar .nav a {
    width: 135px;
}

body .top_bar .nav a:nth-child(2) {
    width: 180px;
}

body .top_bar .nav a:nth-child(2) span {
    padding: 10px 20px;
}

body .top_bar .qiehuan a {
    display: block;
    float: left;
    font-size: 18px;
    color: #fff;
    height: 100px;
    line-height: 100px;
    width: 135px !important;
    text-align: center;
}

body .top_bar .nav {
    position: relative;
}