.left {
    float: left;
}

.right {
    float: right;
}

body {
    max-width: 100%;
}

.banner {
    width: 100%;
    height: 260px;
    line-height: 260px;
    background: #002244;
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    color: #ffffff;
    position: relative;
}

.banner-img1 {
    width: 250px;
    height: 170px;
    position: absolute;
    top: 16px;
    left: 1px;
}

.banner-img2 {
    width: 150px;
    height: 155px;
    position: absolute;
    bottom: 5px;
    right: 200px;
}
.triangle {
    width: 0;
    height: 0;
    border: 28px solid;
    border-color: transparent transparent #fff;
    position:absolute;
    bottom: 0;
    left: 0;
    right: 0;
    margin: 0 auto;
}

.containers {
    width: 1200px;
    margin: 0 auto;
    overflow: hidden;
}

.main-box {
    display: flex;
    flex-wrap: wrap;
    margin-top: 24px;
    justify-content: space-between;
}

.video-demo-box {
    width: 100%;
    /*height: 561px;*/
    padding: 48px 36px;
    background: #f4f9ff;
    border-radius: 8px;
    margin: 0 0 18px 0;
}

.video-demo-box .left {
      margin: 70px 0 0 70px;
  }

.list-img-box {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: #ffffff;
    box-shadow: 0px 2px 8px 0px rgba(0,0,0,0.08); 
    display: flex;
    justify-content: center;
    align-items: center;
    margin-right: 20px;
}

.list-img-box img {
    width: 25px;
    height: 25px;
}

.qrcode-demo-box ,.link-demo-box{
    width: 49%;
    padding: 24px 36px 28px;
    margin-bottom: 18px;
    background: #f8f8ff;
    border-radius: 8px;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.neirong {
    width: 60%;
}

.link-demo-box{
    background: #f1faff;
}

.more-demo-box {
    width: 100%;
    height: 120px;
    background: #f3f7fd;
    border-radius: 8px;
    text-align: center;
}

h3 {
    font-size: 28px;
    font-weight: 700;
    color: #000000;
    line-height: 1;
    margin: 0 0 10px;
    display: flex;
    align-items: center;
}


.qrcode-demo-box h3 {
    justify-content: flex-end;
}

.more-demo-title{
    padding: 16px 0 0;
    justify-content: center;
}

.video-demo-text,.qrcode-demo-text,.link-demo-text,.more-demo-text{
    opacity: 0.65;
    font-size: 16px;
    font-weight: 300;
    color: #000000;
    line-height: 25px;
}

.qrcode-demo-text {
    text-align: right;
}

.link-demo-text {
    text-align: left;
}

.more-demo-text {
    width: 320px;
    margin: 0 auto;
}

.video-demo-more {
    margin-top: 20px;
}

button {
    width: 178px;
    height: 48px;
    line-height: 48px;
    background: #2c95ff;
    border-radius: 24px;
    color: #fff;
    font-size: 16px;
}

.video-demo-play {
    width: 269px;
    height: 560px;
    border: 6px solid #000000;
    border-radius: 25px;
    box-sizing: border-box;
    margin-right: 60px;
}

.qrcode-demo-img {
    width: 130px;
    height: 124px;
}

@media (max-width:1200px){
    .containers {width: 100%;}

    .banner {
        height:180px;
        line-height:180px;
        font-size: 32px;
    }
    .banner-img1 {
        width: 200px;
        height: 140px;
        position: absolute;
        top: 16px;
        left: 1px;
    }
    .banner-img2 {
        width: 130px;
        height: 135px;
        position: absolute;
        bottom: 5px;
        right: 130px;
    }
    .video-demo-box .left {
        margin: 70px 0 0 30px;
    } 
    h3 {
        font-size: 24px;
    }
    .list-img-box {
        width: 40px;
        height: 40px;
    }
    .neirong {
        width: 50%;
    }
    .qrcode-demo-box ,.link-demo-box{
        padding: 24px;
    }
}

@media (max-width:850px){
   .banner-img2 {
        width: 130px;
        height: 135px;
        position: absolute;
        bottom: 0;
        right: 0;
    }
    .video-demo-play {
        margin-right: 10px;
    }
    .qrcode-demo-box ,.link-demo-box{
        width: 100%;
    }
    .video-demo-box .left,.neirong {
        width: 38%;
    }
    
}

@media(max-width:600px) {
    .containers {padding: 0 12px;}

    .video-demo-box,.qrcode-demo-box,
    .link-demo-box,.more-demo-box {
        text-align: center;
    }

    .video-demo-box
    {
        display: table;
    }

    .video-demo-box .left {
        display: table-footer-group;
    }

    .video-demo-box .right {
        display: table-header-group;
    }


    .left,.right,.min-left,.min-right{
        float: none;
        width: 100%;
    }
    
    .video-demo-title {
        justify-content: center;
    }

    .video-demo-text,.qrcode-demo-text,
    .link-demo-text,.more-demo-text{
        font-size: 14px;
        width: 90%;
        margin: auto;
    }

    .video-demo-title, button {
        width: 90%;
        margin: 25px auto 0;
    }
    
    .link-btn {
        width: 50%;
    }
}

@media(max-width:485px) {
    .banner {
        height:117px;
        line-height:117px;
        font-size: 24px;
    }
    .banner-img1 {
        width: 150px;
        height: 117px;
        position: absolute;
        top: 16px;
        left: 1px;
    }
    .banner-img2 {
        width: 90px;
        height: 100px;
        position: absolute;
        bottom: 0;
        right: 0;
    }
    
    .video-demo-play {
        margin: 0;
    }
    .qrcode-demo-box {
        display: table;
    }
    .qrcode-demo-box:nth-child(1) {
        display: table-footer-group;
    }
     .qrcode-demo-box .neirong {
         display: table-header-group;
    }
    h3 {
        font-size: 20px;
    }
    .qrcode-demo-box h3 {
        justify-content: center;
    }
    .qrcode-demo-text {
        width: 85%;
        text-align: center;
    }
    .link-demo-box {
        flex-direction: column;
    }
    .link-demo-box >* {
        width: 85%;
    }
    .link-demo-title {
        justify-content: center;
    }
    .link-demo-text {
        text-align: center;
    }
}