@media screen and (max-width: 768px) {
    .w1140 {
      width: 100%;
    }
    .w1200 {
      width: 100%;
    }
    header {
      padding: 0 20px;
      position: relative;
    }
    header .phone .btn {
      text-align: right;
      color: var(--main-color-primary);
      font-size: 1.5rem;
    }
    .phonenav {
      width: 100%;
      background-color: #f9f9f9;
      /* position: fixed; */
    }
    .phonenav ul, .phonenav li {
      padding: 0;
      margin: 0;
    }
    .phonenav ul li {
      padding: 0 20px;
      list-style: none;
      position: relative;
    }
    .phonenav ul li .sub {
      display: none;
    }
    .phonenav ul li a {
      color: var(--main-color-primary);
      display: inline-block;
      padding: 10px 0;
      font-size: 12px;
    }
    .phonenav > ul > li > a {
      width: 94%;
    }
    .phonenav .down i {
      color: var(--main-color-primary);
    }
    .main {
      margin-top: 0;
    }
    .main section.s1 {
      padding: 0;
    }

    .main section.s2 .box .item .cont p {
      font-size: 12px;
    }
    .main .sort h3 {
      font-size: 20px;
    }
    .main .sort p {
      font-size: 14px;
    }

    .main section.bg .box {
      text-align: center;
    }

    .main section.s3 .box {
      min-height: 400px;
    }
    .main section.s3 .box h3 {
      text-align: center;
      padding-bottom: 0;
      font-size: 23px;
      line-height: 3rem;
    }

    .main section.bg .btn {
      padding: 5px 20px;
      position: absolute;
      font-size: 14px;
    }

    .main section.s4 {
      background-position: center left;
    }
    .main section.s4 .item h3{
      font-size: 24px;
    }

    .main section.s5 {
      /* background-position: -30px -27px;
      height: 70vh; */
      height: 95vh;
    }
    .main section.s5 .item {
      padding: 0;
      font-size: 14px;
      padding-right: 50px;
    }
    .main section.s6 > div {
      padding: 0;
    }
    .main section.s6 .item h3 {
      font-size: 20px;
    }

    .main section.s9 .pic, .main section.s9 .item {
      padding: 15px;
    }
    .main section.s9 .item h3 {
      font-size: 20px;
      font-weight: bolder;
    }
    .main section.s9 .item p {
      font-size: 12px;
    }
    .main section.s9 .item .cont input {
      width: 12rem;
    }
    .main section.s9 .item .cont textarea {
      max-width: 100%;
      height: 5rem;
    }

    .footer .nav {
      text-align: center;
    }
    .footer .nav a {
      font-size: 12px;
    }
    .footer .nav p {
      margin: 1rem 0;
    }
    .footer .copyright .row {
      margin: 0 auto;
      text-align: center;
    }
    .footer .copyright .social {
      text-align: center;
    }

    /* news */
    
    .main.news .links > * {
      text-align: center !important;
      margin: 0.5rem 0;
    }
    .main.news .links span {
      display: none;
    }

    /* case */
    .main.case .box {
      padding: 1rem;
    }
    .main.case .links > * {
      text-align: center !important;
      margin: 0.5rem 0;
    }
    .main.case .links span {
      display: none;
    }

    /* solutions */
    .main.solutions .top .b span {
      display: table;
      background-color: var(--main-color-primary);
    }
    .main.solutions .select-wrap .top .tab a {
      font-size: 12px;
    }
    .main.solutions .select-wrap .top .dec {
      padding: 0;
      max-width: 82%;
    }
    .main.solutions .select-wrap .top .dec p {
      font-size: 12px;
    }

    .main.about .s4 .box {
      padding-left: 0;
    }
    .main.about .s5 .box {
      padding: 50px 20px;
    }
    .main.about .s5 .box h3 {
      margin-bottom: 1rem;
      font-size: 23px;
    }
    .main.about .s5 .box p {
      font-size: 16px;
      line-height: 1.8rem;
    }
    .main.about .s7 h3 {
      font-size: 1.2rem;
    }
    .main.about .s7 p {
      font-size: 12px;
    }
    .main.about .s8 .top p {
      font-size: 12px;
    }

    /* productlist */
    .main.productlist .s1 {
      min-height: 20vh;
    }
    .main.productlist .top img {
      bottom: 0;
      margin-bottom: 0;
      max-width: 100%;
    }

    /* search */
    .main.search .s1 {
      padding: 0;
    }
    .main.search .top img {
      bottom: 0;
      margin-bottom: 0;
    }
    .youtube-video {
      height: 200px;
    }

    /* contacts */
    .main.contacts .s1 {
      padding: 150px 0;
    }
}

@media screen and (max-width: 576px) {
  .main section.s4 {
    background-image: unset !important;
  }
  .main section.s4 > div {
    padding: 0; 
  }
  .main section.s4 .item h3 {
    font-size: 18px;
  }
  .main section.s5 .item {
    padding: 0;
  }
  .main section.s5 .item p {
    font-size: 12px;
  }
  .main section.s5 {
    background-position: center center;
    height: 60vh;
  }

  .main section.s6 {
    background-image: unset !important;
  }
  .main section.s7 h3 {
    font-size: 23px;
  }
  .main section.s7 p {
    font-size: 16px;
    line-height: 1.8rem;
  }
  .main.productlist .tab a {
    flex: 1 0 100%;
  }
  
  .main.product .pic .code {
    position: absolute;
    bottom: 1rem;
    right: 1rem;
    text-align: right;
  }
}