/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Microsoft YaHei", "Hiragino Sans GB", "WenQuanYi Micro Hei", sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

a {
    text-decoration: none;
    color: #3A5998;
    transition: color 0.3s ease;
}

a:hover {
    color: #1D3C78;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 15px;
    color: #222;
}

h1 {
    font-size: 2.5rem;
    color: #fff;
    text-shadow: 1px 1px 3px rgba(0, 0, 0, 0.6);
}

h2 {
    font-size: 2rem;
    position: relative;
    padding-bottom: 15px;
    margin-bottom: 30px;
    text-align: center;
}

h2:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background-color: #3A5998;
}

h3 {
    font-size: 1.5rem;
}

p {
    margin-bottom: 15px;
}

ul, ol {
    margin-bottom: 15px;
    padding-left: 20px;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* 头部样式 */
header {
    background-color: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
    max-width: 1200px;
    margin: 0 auto;
}

.logo a {
    display: flex;
    align-items: center;
    color: #333;
    font-weight: 700;
    font-size: 1.5rem;
}

.logo svg {
    margin-right: 10px;
}

nav ul {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

nav ul li {
    margin-left: 20px;
}

nav ul li a {
    color: #333;
    font-weight: 500;
    padding: 10px 0;
    position: relative;
}

nav ul li a:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: #3A5998;
    transition: width 0.3s ease;
}

nav ul li a:hover:after {
    width: 100%;
}

/* 轮播背景样式 */
.banner-container {
    position: relative;
    height: 500px;
    overflow: hidden;
}

.banner-slides {
    height: 100%;
    position: relative;
}

.slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.slide.active {
    opacity: 1;
}

.slide img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: -1;
}

.slide-content {
    text-align: center;
    max-width: 800px;
    padding: 20px;
    background-color: rgba(0, 0, 0, 0.5);
    border-radius: 10px;
    color: #fff;
    z-index: 1;
}

.banner-dots {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.5);
    margin: 0 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.dot.active {
    background-color: #fff;
}

/* 模块通用样式 */
.module {
    padding: 60px 0;
}

.module:nth-child(odd) {
    background-color: #fff;
}

.module:nth-child(even) {
    background-color: #f8f9fa;
}

.module-content {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    margin: 0 -15px;
}

.text-content, .image-content {
    flex: 1;
    padding: 0 15px;
    min-width: 300px;
}

/* 概述模块样式 */
.overview .text-content {
    flex: 2;
}

.overview .image-content {
    flex: 1;
}

.overview .image-content img {
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

/* 历史背景模块样式 */
.timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
}

.timeline:before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 100%;
    background-color: #3A5998;
}

.timeline-item {
    position: relative;
    margin-bottom: 40px;
}

.timeline-content {
    position: relative;
    padding: 20px;
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    max-width: 80%;
    margin-left: auto;
    margin-right: auto;
}

.timeline-item:nth-child(odd) .timeline-content {
    margin-right: 0;
}

.timeline-item:nth-child(even) .timeline-content {
    margin-left: 0;
}

.timeline-content h3 {
    color: #3A5998;
    margin-bottom: 10px;
}

.timeline-content img {
    margin-top: 15px;
    border-radius: 5px;
}

/* 研究成果模块样式 */
.card-container {
    display: flex;
    flex-wrap: wrap;
    margin: 0 -15px;
}

.card {
    flex: 1;
    min-width: 250px;
    margin: 15px;
    background-color: #fff;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.15);
}

.card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.card-content {
    padding: 20px;
}

.card-content h3 {
    color: #3A5998;
    margin-bottom: 10px;
}

/* 专题文章模块样式 */
.article-list {
    max-width: 900px;
    margin: 0 auto;
}

.article-item {
    display: flex;
    margin-bottom: 40px;
    background-color: #fff;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.article-image {
    flex: 1;
    min-width: 200px;
    max-width: 300px;
}

.article-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.article-content {
    flex: 2;
    padding: 20px;
}

.article-content h3 {
    color: #3A5998;
    margin-bottom: 10px;
}

.article-content p {
    margin-bottom: 15px;
    display: -webkit-box;
    -webkit-line-clamp: 5;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.read-more {
    display: inline-block;
    padding: 8px 15px;
    background-color: #3A5998;
    color: #fff;
    border-radius: 5px;
    font-weight: 500;
    transition: background-color 0.3s ease;
}

.read-more:hover {
    background-color: #1D3C78;
    color: #fff;
}

/* 专家观点模块样式 */
.expert-container {
    display: flex;
    flex-wrap: wrap;
    margin: 0 -15px;
}

.expert-item {
    flex: 1;
    min-width: 300px;
    margin: 15px;
    display: flex;
    background-color: #fff;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    padding: 20px;
}

.expert-avatar {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    overflow: hidden;
    margin-right: 20px;
    flex-shrink: 0;
}

.expert-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.expert-info {
    flex: 1;
}

.expert-title {
    color: #666;
    font-style: italic;
    margin-bottom: 10px;
}

.expert-quote {
    position: relative;
    padding-left: 20px;
    border-left: 3px solid #3A5998;
    font-style: italic;
    color: #555;
}

/* APP下载模块样式 */
.app-content {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
}

.app-info {
    flex: 2;
    padding-right: 30px;
}

.app-screenshot {
    flex: 1;
    min-width: 300px;
}

.app-screenshot img {
    border-radius: 10px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.app-download-buttons {
    display: flex;
    margin-top: 20px;
}

.download-btn {
    display: flex;
    align-items: center;
    padding: 10px 20px;
    background-color: #3A5998;
    color: #fff;
    border-radius: 5px;
    margin-right: 15px;
    transition: background-color 0.3s ease;
}

.download-btn:hover {
    background-color: #1D3C78;
    color: #fff;
}

.download-btn img {
    width: 24px;
    height: 24px;
    margin-right: 10px;
}

/* 页脚样式 */
footer {
    background-color: #222;
    color: #aaa;
    padding: 60px 0 30px;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

.footer-top {
    display: flex;
    flex-wrap: wrap;
    margin-bottom: 40px;
}

.footer-column {
    flex: 1;
    min-width: 250px;
    margin-bottom: 30px;
    padding: 0 15px;
}

.footer-column h3 {
    color: #fff;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-column h3:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background-color: #3A5998;
}

.footer-column ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-column ul li {
    margin-bottom: 10px;
}

.footer-column ul li a {
    color: #aaa;
    transition: color 0.3s ease;
}

.footer-column ul li a:hover {
    color: #fff;
}

.contact-info li {
    display: flex;
    align-items: center;
}

.contact-info li i {
    margin-right: 10px;
    color: #3A5998;
}

.footer-middle {
    padding: 30px 0;
    border-top: 1px solid #333;
    border-bottom: 1px solid #333;
}

.footer-middle h3 {
    color: #fff;
    margin-bottom: 20px;
}

.footer-middle ul {
    display: flex;
    flex-wrap: wrap;
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-middle ul li {
    margin-right: 20px;
    margin-bottom: 10px;
}

.footer-middle ul li a {
    color: #aaa;
}

.footer-middle ul li a:hover {
    color: #fff;
}

.footer-bottom {
    padding-top: 30px;
    text-align: center;
}

.copyright, .icp {
    margin-bottom: 10px;
}

/* 响应式样式 */
@media (max-width: 992px) {
    .header-container {
        flex-direction: column;
        padding: 15px;
    }
    
    .logo {
        margin-bottom: 15px;
    }
    
    nav ul {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    nav ul li {
        margin: 5px 10px;
    }
    
    .banner-container {
        height: 400px;
    }
    
    .timeline:before {
        left: 20px;
    }
    
    .timeline-content {
        max-width: calc(100% - 40px);
        margin-left: 40px !important;
        margin-right: 0 !important;
    }
    
    .article-item {
        flex-direction: column;
    }
    
    .article-image {
        max-width: 100%;
    }
    
    .expert-item {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .expert-avatar {
        margin-right: 0;
        margin-bottom: 15px;
    }
    
    .expert-quote {
        padding-left: 0;
        border-left: none;
        border-top: 3px solid #3A5998;
        padding-top: 15px;
    }
    
    .app-info {
        padding-right: 0;
        margin-bottom: 30px;
    }
}

@media (max-width: 576px) {
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    h3 {
        font-size: 1.2rem;
    }
    
    .banner-container {
        height: 300px;
    }
    
    .module {
        padding: 40px 0;
    }
    
    .app-download-buttons {
        flex-direction: column;
    }
    
    .download-btn {
        margin-right: 0;
        margin-bottom: 15px;
    }
}