/* 清浮动 */
.clear:after {
    display: block;
    content: '';
    clear: both;
}

/* banner */
.dh-banner {
    position: relative;
    margin-top: 146px;
    font-family: 'SimHei', 'MT Light';
}

.banner-content img {
    width: calc(100vw - 17px);
}

.banner-desc {
    position: absolute;
    top: 100px;
    left: 200px;
}

.dh-bannerp {
    font-family: 'SimHei', 'MT Light';
    height: 56px;
    font-size: 3vw;
    line-height: 72px;
    letter-spacing: 0px;
    color: #ffffff;
}

/* page-nav */
.nav-sec {
    height: 40px;
    margin-top: 28px;
}

.nav-sec-li {
    float: left;
    height: 17px;
    font-size: 18px;
    letter-spacing: 3px;
    color: #333333;
    margin-left: 81px;
    padding-bottom: 40px;
    border-bottom: 2px;
}

.nav-sec-li-active {
    border-bottom: 2px solid #8f2e33;
}

/*content*/
.dev-all {
    background-color: rgb(234, 234, 234);
}

.dev-content-title {
    width: 645px;
    padding-top: 50px;
    font-size: 2vw;
    letter-spacing: 5px;
    font-family: 'SimHei', 'MT Light';
    color: #333333;
    margin: 0px auto 0;
}

.dev-content-p {
    width: 645px;
    font-size: 18px;
    letter-spacing: 3px;
    font-family: 'SimHei', 'MT Light';
    margin: 20px auto 24px;
    line-height: 32px;
    color: #333333;
}

.dev-content-img {
    width: 645px;
    margin: 0 auto;
}

.dev-img {
    display: block;
    margin: 40px auto 0;
    width: 62vw;
}

.dev-morep {
    display: none;
    width: 645px;
    font-size: 18px;
    letter-spacing: 3px;
    margin: 20px auto 24px;
    font-family: 'SimHei', 'MT Light';
    line-height: 32px;
    color: #333333;
}

.doubleimg {
    width: 62vw;
    margin: 0 auto;
    margin-top: 2vw;
}

.rightimg {
    float: right;
}

.doubleimg2 {
    width: 62vw;
    margin: 30px auto 0px;
}

.devimgup {
    display: block;
    margin: 2vw auto 0;
}

.showandhide {
    display: block;
}

.fill_blank {
    width: 100%;
    height: 80px;
    background-color: rgb(234, 234, 234);
    margin-top: -24px;
}

.nav-sec-li:hover {
    cursor: pointer;
}