.about-box{display: flex;justify-content: center;}
.about-box .about-item{display: none;background-color: #fff;}
.about-item.selected{display: block;}
.about-item-one{padding-bottom: 100px;}
.about-item-one .company-info{width: 812px;margin:0 auto;text-align: center;}
.about-item-one .company-info>h4{padding:92px 0 55px;font-size: 30px;color: #2A2E2E;line-height: 30px;}
.about-item-one .company-info>p{color: #2A2E2E;font-size: 14px;line-height: 36px;}

.about-item-two{display: flex;justify-content: center;padding: 60px 0 70px;}
.about-item-two .develop-path li{position: relative;display: flex;align-items: center;height: 95px;}
.about-item-two .develop-path li>em{width: 60px;color: #2A2E2E;font-size: 26px;font-weight: bold;line-height: 26px;}
.about-item-two .develop-path li>i{width: 15px;height: 15px;margin:0 106px;border-radius: 50%;background-color: #E0E0E0;}
.about-item-two .develop-path li>p{font-size: 14px;color: #2A2E2E;line-height: 26px;}
.about-item-two .develop-path li:after{position: absolute;top: 64px;left: 173px;width: 1px;height: 60px;content: "";background-color: #E0E0E0;}
.about-item-two .develop-path li:last-child:after{display: none;}

.about-item-three{margin:100px auto 70px;}
.about-item-three .product-item{display: flex;width: 820px;padding:40px;margin:0 auto 30px;background-color: #FBFCFD;}
.about-item-three .product-item dt>img{width: 90px;height: 90px;margin-right: 40px;}
.about-item-three .product-item dd{padding-top: 16px;}
.about-item-three .product-item dd>h5{font-size: 26px;color: #2A2E2E;line-height: 26px;font-weight: bold;}
.about-item-three .product-item dd .pro-intro{margin-bottom: 10px;font-size: 16px;color: #5F6464;line-height: 48px;}
.about-item-three .product-item dd .pro-desc{font-size: 13px;color: #5F6464;line-height: 24px;}

.about-item-four{margin-bottom: 60px;}
.about-item-four .social-box{width: 835px;margin: 0 auto;font-size: 14px;color: #2A2E2E;}
.about-item-four .social-box .social-intro{margin:108px 0;line-height: 30px;}
.about-item-four .social-box .social-desc .social-tit{margin-bottom: 48px;font-size: 18px;line-height: 18px;font-weight: bold;}
.about-item-four .social-box .social-desc .social-info{line-height: 30px;margin-bottom: 30px;}
.about-item-four .social-box .social-desc .social-img{display: flex;justify-content: space-between;margin-bottom: 110px;}
.about-item-four .social-box .social-desc .social-img>img{width: 256px;height: 216px;}