* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Source Han Sans CN', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    color: #292929;
    line-height: 1.6;
    overflow-x: hidden;
}

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 81px;
    background: rgba(225, 234, 243, 0.8);
    backdrop-filter: blur(10px);
    z-index: 1000;
    display: flex;
    justify-content: center;
    align-items: center;
}

.navbar-container {
    width: 100%;
    max-width: 1600px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 40px;
    margin: 0 auto;
}

.logo {
    display: flex;
    align-items: center;
    font-size: 28px;
    font-weight: bold;
    color: #292929;
}

.logo img {
    height: 28px;
    margin-right: 10px;
}

.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li {
    margin-left: 30px;
}

.nav-links a {
    text-decoration: none;
    color: #292929;
    font-size: 20px;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover,
.nav-links a.active {
    color: #B84F0A;
}

/* 移动端菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    cursor: pointer;
    z-index: 1001;
}

.menu-toggle span {
    display: block;
    height: 3px;
    width: 100%;
    background-color: #292929;
    border-radius: 3px;
    transition: all 0.3s ease-in-out;
    transform-origin: center;
}

.banner {
    height: 100vh;
    min-height: 600px;
    max-height: 881px;
    background: url('../image/product/bk001.png') center top no-repeat;
    background-size: cover;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
    position: relative;
}

.banner-content {
    max-width: 90%;
    width: 800px;
    margin: 0 auto;
    padding: 0 20px;
}

.banner h1 {
    font-family: "SourceHanSansCN-Bold";
    font-size: 40px;
    color: #143C84;
    letter-spacing: 0;
    text-align: center;
    font-weight: 700;
    margin-bottom: 30px;
}
.banner h3 {
  font-family: "SourceHanSansCN-Medium";
font-size: 28px;
color: #292929;
letter-spacing: 0;
font-weight: 500;
text-align: left;
margin-top: 60px;
}

.banner p {
    font-family: "SourceHanSansCN-Medium";
    font-size: 24px;
    color: #143C84;
    letter-spacing: 0;
    line-height: 30px;
    font-weight: 500;
    text-align: left;
    text-indent: 50px;
}

.section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 40px;
    font-weight: bold;
    color: #143C84;
    margin-bottom: 60px;
}

.container {
    width: 100%;
    max-width: 1300px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 安全应急管理信息系统 */
.system-intro {
    background: #fff;
    padding: 80px 0;
}
.system-back {
  background: url('../image/product/bk002.png') center/cover no-repeat;
}

.intro-content {
    /* display: flex;
    align-items: center;
    gap: 50px; */
}
.intro-div img {
  width: 100%;
  height: auto;
}

.intro-text h2 {
    font-family: "SourceHanSansCN-Bold";
    font-size: 40px;
    color: #143C84;
    letter-spacing: 0;
    text-align: center;
    font-weight: 700;
    margin-bottom: 20px;
}
.intro-text h3 {
    font-family: "SourceHanSansCN-Bold";
    font-size: 20px;
    color: #143C84;
    letter-spacing: 0;
    text-align: center;
    font-weight: 400;
    margin-bottom: 20px;
}

.intro-text p {
    font-size: 24px;
    color: #143C84;
    line-height: 1.6;
    text-align: justify;
}

.intro-div {
  /* display: flex;
  flex-direction: row; */
}
.intro-div img {
  max-width: 100%;
  height: auto;
}
/* .intro-div div:first-child {
  writing-mode: vertical-rl;
  font-family: "SourceHanSansCN-Medium";
  font-size: 28px;
  color: #292929;
  letter-spacing: 0;
  font-weight: 500;
  text-align: center;
  margin-right: 20px;
} */

.dds-title {
  font-family: "SourceHanSansCN-Medium";
  font-size: 22px;
  color: #20488E;
  letter-spacing: 0;
  line-height: 40px;
  font-weight: 500;
  text-indent: 30px;
  margin-bottom: 20px;
}

/* 核心系统架构 */
.system-architecture {
    background: #E1EAF3;
    padding: 80px 0;
}

.architecture-content {
    text-align: center;
}

.architecture-image {
    margin: 40px 0;
}

.architecture-image img {
    max-width: 100%;
    border-radius: 8px;
}

.core-features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.feature-item {
    display: flex;
    align-items: flex-start;
    flex-direction: row;
    border-radius: 8px;
    min-height: 60px;
}

.feature-icon {
    width: 43px;
    height: 43px;
    margin-right: 10px;
    flex-shrink: 0;
}

.feature-text {
    font-family: "SourceHanSansCN-Medium";
    font-size: 20px;
    color: #292929;
    letter-spacing: 0;
    line-height: 26px;
    font-weight: 400;
    text-align: left;
}

.feature-text p {
    font-size: 20px;
    color: #292929;
    line-height: 1.5;
}

/* 有巢国产三维设计软件 */
.ych-software {
    background: #fff;
    padding: 80px 0;
}

.ych-content {
    display: flex;
    align-items: center;
    gap: 50px;
}

.ych-text {
    flex: 1;
}

.ych-text h2 {
    font-size: 40px;
    color: #143C84;
    margin-bottom: 30px;
    text-align: center;
}

.ych-text p {
    font-size: 24px;
    color: #20488E;
    line-height: 1.6;
    text-align: justify;
}

.ych-image {
    flex: 1;
}

.ych-image img {
    width: 100%;
    border-radius: 8px;
}

.advantages {
    margin-top: 50px;
}

.advantages h3 {
    font-size: 28px;
    color: #292929;
    margin-bottom: 20px;
}

.advantage-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.advantage-item {
    display: flex;
    align-items: center;
    min-height: 70px;
}

.advantage-item img {
    width: 60px;
    height: 60px;
    margin-right: 15px;
    flex-shrink: 0;
}

.advantage-text {
    font-size: 20px;
    color: #292929;
    line-height: 1.4;
}

/* 3DDS和3DDC */
.modules {
    background: #E1EAF3;
    padding: 80px 0;
}

.modules-container {
    display: flex;
    gap: 50px;
    flex-wrap: wrap;
}
.dds-back {
    background: url('../image/product/bk004.png') center/cover no-repeat; 
  }

.module {
    flex: 1;
    min-width: 300px;
    padding: 30px;
}

.module h3 {
    font-size: 28px;
    color: #292929;
    text-align: center;
    margin-bottom: 20px;
}

.module-image {
    text-align: center;
    margin: 20px 0;
}

.module-image img {
    max-width: 100%;
    border-radius: 8px;
}

.module-details {
    font-size: 20px;
    color: #292929;
    line-height: 1.6;
}

.highlight {
    color: #D98E04;
    font-weight: 500;
}

/* 3DDC校审流程 */
.process-flow {
    background: #fff;
    padding: 80px 0;
    text-align: center;
}

.process-image {
    margin: 40px 0;
}

.process-image img {
    max-width: 100%;
    border-radius: 8px;
}

.process-description {
    display: flex;
    flex-direction: row;
}
.process-description > div {
  border: 1px #000 dashed;
  border-radius: 30px;
  padding: 20px;
  text-align: left;
  font-family: "SourceHanSansCN-Medium";
  font-size: 24px;
  color: #143C84;
  letter-spacing: 0;
  line-height: 30px;
  font-weight: 500;
}

/* 自主研发的渲染引擎 */
.render-engine {
    background: #E1EAF3;
    padding: 80px 0;
    text-align: center;
}

.engine-content {
    
}

.engine-text {
    flex: 1;
    text-align: left;
}

.engine-text h2 {
    font-family: "SourceHanSansCN-Bold";
    font-size: 40px;
    color: #143C84;
    letter-spacing: 0;
    text-align: center;
    font-weight: 700;
    margin-bottom: 20px;
}
.engine-text h4 {
  font-family: "SourceHanSansCN-Medium";
  font-size: 24px;
  color: #143C84;
  letter-spacing: 0;
  font-weight: 500;
  text-align: center;
    margin-bottom: 20px;
}

.engine-points {
    font-size: 24px;
    color: #292929;
    line-height: 1.8;
}

.point {
    margin-bottom: 20px;
}

.engine-video-container {
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  gap: 30px;
}

.point-highlight {
    font-family: "SourceHanSansCN-Medium";
    font-size: 24px;
    color: #D98E04;
    letter-spacing: 0;
    line-height: 36px;
    font-weight: 500;
}

.engine-video {
    width: 100%;
    max-width: 687px;
    height: auto;
    aspect-ratio: 687/396;
    margin-right: 50px;
}


/* 核心特点 */
.engine-back {
  background: url('../image/product/bk006.png') center/cover no-repeat;
}
.core-characteristics {
    background: #fff;
    padding: 80px 0;
}

.characteristics-container {
  padding-top: 30px;
}

.characteristic-column {
    display: flex;
    flex-direction: row;
    margin-bottom: 30px;
}
.characteristic-column > img {
  width: 53px;
  height: 53px;
  margin-right: 5px;
}

.characteristic-column h3 {
    font-size: 20px;
    color: #D98E04;
}

.characteristic-item {
    font-size: 20px;
    color: #292929;
    line-height: 1.5;
    text-align: left;
}

/* 仿真模型 */
.simulation-models {
    background: #E1EAF3;
    padding: 80px 0;
}

.models-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.model-group {
    padding: 30px;
    border-radius: 8px;
}
.model-group p {
  font-family: "SourceHanSansCN-Medium";
  font-size: 20px;
  color: #292929;
  letter-spacing: 0;
  line-height: 26px;
  font-weight: 500;
  margin-bottom: 20px;
}

.model-group h3 {
    font-family: "SourceHanSansCN-Medium";
    font-size: 24px;
    color: #143C84;
    letter-spacing: 0;
    font-weight: 500;
    text-align: center;
    margin-bottom: 20px;
}
.model-group p > span {
  font-family: "SourceHanSansCN-Medium";
  font-size: 20px;
  color: #D98E04;
  letter-spacing: 0;
  line-height: 26px;
  font-weight: 500;
}

.models-list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.model-item {
    text-align: center;
    min-height: 120px;
}

.model-item img {
    width: 100%;
    max-width: 153px;
    height: auto;
    aspect-ratio: 153/80;
    margin-bottom: 10px;
}

.model-name {
    font-size: 20px;
    color: #292929;
    line-height: 1.3;
}

/* 核心理念 */
.core-concept {
    background: url('../image/product/bk007.png') center top no-repeat;
    background-size: cover;
    padding: 100px 0;
    text-align: center;
}

.concept-banner {
  width: 95%;
  background: #143A89;
  border-radius: 4px;
  padding: 10px 20px;
  color: white;
  font-size: 24px;
  display: inline-block;
  margin: 0 auto;
  margin-left: 29px;
  text-align: center;
}

/* 尾部 */
.footer {
    background: url('../image/index/bk005.png') center/cover no-repeat;
    color: #E8EFF2;
    padding: 40px 0 20px;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.footer-top {
    display: flex;
    justify-content: space-between;
    margin-bottom: 30px;
}

.footer-info {
    flex: 1;
}

.footer-info h3 {
    font-size: 20px;
    margin-bottom: 15px;
}

.footer-info p {
    font-family: SourceHanSansSC-Medium;
    font-size: 20px;
    color: #E8EFF2;
    letter-spacing: 0;
    font-weight: 500;
}

.footer-contact {
    flex: 1;
}

.footer-contact h3 {
    font-size: 20px;
    margin-bottom: 15px;
}

.footer-contact p {
    font-size: 14px;
    line-height: 1.6;
    margin-bottom: 10px;
}

.footer-divider {
    height: 1px;
    background: rgba(216, 216, 216, 0.42);
    margin: 20px 0;
}

.footer-bottom {
    text-align: center;
    font-size: 16px;
    padding: 20px 0;
    display: flex;
    flex-direction: row;
    
}

.footer-bottom p {
    margin: 5px 0;
}

/* 响应式设计 */
@media (max-width: 1400px) {
    .banner {
        height: 90vh;
        /* max-height: 800px; */
    }
    
    .banner-content {
        max-width: 85%;
    }
    
}

@media (max-width: 1200px) {
    .container {
        width: 95%;
        padding: 0 15px;
    }
    
    .footer-content {
        width: 95%;
    }
    
    .navbar-container {
        padding: 0 30px;
    }
    
    .banner {
        height: 85vh;
        /* max-height: 750px; */
    }
    
    .banner h1 {
        font-size: 36px;
    }
    
    .banner p {
        font-size: 22px;
    }
}

@media (max-width: 2560px) { 
  .engine-container { 
    max-width: 1900px;
  }
}

@media (max-width: 1728px) { 
  .system-back {
      background: url('../image/product/bk006.png') no-repeat;
      background-size: auto 1218px;
    }
  .dds-back {
      background: url('../image/product/bk004.png') no-repeat; 
      background-size: auto 1118px;
    }
    .engine-back {
      background: url('../image/product/bk006.png') no-repeat;
      background-size: auto 1400px;
    }
    .engine-container {
      max-width: 1280px;
    }
    .engine-video {
        height: 400px;
        aspect-ratio: 687/396;
        text-align: center;
    }
    .characteristics-container {
      width: 400px
    }
    
}

/* 针对16:10屏幕比例（1440x900等）的适配 */
@media (max-width: 1440px) and (min-width: 1201px) {
    .banner {
        height: 95vh;
        /* max-height: 850px; */
    }
    
    .banner-content {
        max-width: 90%;
    }
    .engine-container { 
      max-width: 1290px;
    }

    .intro-content {
        display: flex;
        align-items: center;
        gap: 50px;
    }
    .engine-video-container {
      display: block;
    }
    .characteristics-container {
      width: 100%;
    }
    .dds-back {
      background: url('../image/product/bk004.png') no-repeat; 
      background-size: auto 1030px;
    }
    .engine-back {
      background: url('../image/product/bk006.png') no-repeat;
      background-size: auto 2030px;
    }
    .system-back {
      background: url('../image/product/bk006.png') no-repeat;
      background-size: auto 1030px;
    }
    .engine-video {
        height: 400px;
        max-width: 1160px;
        aspect-ratio: 687/396;
        text-align: center;
    }
    
    .core-features {
        gap: 25px;
    }
    
    .advantage-list {
        gap: 15px;
    }
    .system-intro {
      padding: 30px 20px;
    }
    .modules-container {
        gap: 40px;
    }
    /* .system-intro {
      height: 526px;
    } */
    .intro-div {
      text-align: center;
    }
    .intro-text h2, .intro-text h3 {
      margin-bottom: 5px;
    }
    
    .module-height {
      padding-bottom: 0px;
    }

    .feature-text {
        font-size: 18px;
        line-height: 24px;
    }
}

@media (max-width: 1024px) {
  .module-height {
    padding-bottom: 0px;
  }
  
  .intro-content {
    display: flex;
    align-items: center;
    gap: 10px;
  }
  .intro-div img {
    width: 90%;
    height: 70%;
  }
}

@media (max-width: 992px) {
    .intro-content,
    .ych-content,
    .engine-content,
    .characteristics-container,
    .modules-container {
        flex-direction: column;
        gap: 30px;
    }
    
    .intro-text,
    .ych-text,
    .engine-text {
        text-align: center;
    }
    
    .engine-text {
        text-align: left;
    }
    
    .core-features,
    .advantage-list,
    .models-grid {
        grid-template-columns: 1fr;
    }
    
    .feature-item {
        flex-direction: column;
        text-align: center;
    }
    
    .feature-icon {
        margin-right: 0;
        margin-bottom: 15px;
    }
    
    .section-title {
        font-size: 32px;
    }
    
    .intro-text h2,
    .ych-text h2,
    .engine-text h2 {
        font-size: 32px;
    }
    
    .intro-text p,
    .ych-text p,
    .process-description,
    .engine-points {
        font-size: 20px;
    }
    
    .feature-text h3 {
        font-size: 24px;
    }
    
    .models-list {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-top {
        flex-direction: column;
        gap: 30px;
    }
    
    .footer-links {
        flex-wrap: wrap;
    }
    
    .navbar-container {
        padding: 0 30px;
    }
}

@media (max-width: 768px) {
    .menu-toggle {
        display: flex;
    }
    
    .nav-links {
        position: fixed;
        top: 81px;
        left: 0;
        width: 100%;
        height: calc(100vh - 81px);
        background: rgba(225, 234, 243, 0.95);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        clip-path: circle(0px at top right);
        transition: all 0.3s ease-in-out;
        z-index: 1000;
        display: none;
    }
    
    .nav-links.active {
        display: flex;
        clip-path: circle(1500px at top right);
    }
    
    .nav-links li {
        margin: 20px 0;
    }
    
    .nav-links a {
        font-size: 24px;
    }
    
    .navbar-container {
        padding: 0 20px;
    }
    
    .banner {
        height: 70vh;
        min-height: 500px;
        max-height: 600px;
    }
    
    .banner h1 {
        font-size: 32px;
    }
    
    .banner p {
        font-size: 20px;
        text-indent: 30px;
    }
    
    .section {
        padding: 60px 0;
    }
    
    .section-title {
        font-size: 28px;
        margin-bottom: 40px;
    }
    
    .intro-text h2,
    .ych-text h2,
    .engine-text h2 {
        font-size: 28px;
        margin-bottom: 20px;
    }
    
    .intro-text p,
    .ych-text p,
    .process-description,
    .engine-points {
        font-size: 18px;
    }
    
    .feature-text h3 {
        font-size: 20px;
    }
    
    .advantage-list {
        grid-template-columns: 1fr;
    }
    
    .models-list {
        grid-template-columns: 1fr;
    }
    
    .concept-banner {
        font-size: 20px;
        padding: 15px 30px;
        margin-left: 0;
        width: 100%;
    }
    
    .footer-top {
        flex-direction: column;
        gap: 10px;
    }
    
    .footer-links a {
        font-size: 18px;
    }
    
    .footer-info {
        font-size: 13px;
    }
    
    .process-description {
        flex-direction: column;
        gap: 20px;
    }
    
    .process-description > div {
        margin-right: 0;
        width: 100%;
    }
}

@media (max-width: 480px) {
    .header {
        height: 70px;
        padding: 0 15px;
    }
    
    .logo {
        font-size: 24px;
    }
    
    .banner {
        height: 500px;
        margin-top: 70px;
    }
    
    .banner h1 {
        font-size: 28px;
    }
    
    .banner p {
        font-size: 18px;
    }
    
    .section {
        padding: 50px 0;
    }
    
    .section-title {
        font-size: 24px;
    }
    
    .intro-text h2,
    .ych-text h2,
    .engine-text h2 {
        font-size: 24px;
    }
    
    .intro-text p,
    .ych-text p,
    .process-description,
    .engine-points,
    .characteristic-item,
    .advantage-text,
    .module-details {
        font-size: 16px;
    }
    
    .feature-text h3 {
        font-size: 18px;
    }
    
    .process-description {
        border-radius: 20px;
        padding: 20px;
    }
    
    .concept-banner {
        font-size: 18px;
        padding: 12px 25px;
    }
    
    .footer-logo {
        font-size: 24px;
    }
    
    .footer-links a {
        font-size: 16px;
    }
    
    .footer-bottom {
        font-size: 14px;
    }
}