/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

body {
    background-color: #f8f9fa;
    color: #333;
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
}

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

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

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo {
    display: flex;
    align-items: center;
}

.logo-img {
    width: 60px;
    height: 60px;
    margin-right: 15px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    background-color: transparent;
}

.logo-img img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.logo-text {
    font-size: 20px;
    font-weight: 600;
    color: #2c5aa0;
    line-height: 1.2;
}

.logo-subtitle {
    font-size: 14px;
    color: #666;
    margin-top: 3px;
}

/* 导航栏样式 */
nav ul {
    display: flex;
    list-style: none;
}

nav li {
    margin-left: 30px;
}

nav a {
    font-weight: 500;
    padding: 8px 0;
    position: relative;
    transition: color 0.3s;
}

nav a:hover {
    color: #2c5aa0;
}

nav a.active {
    color: #2c5aa0;
    font-weight: 600;
}

nav a.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: #2c5aa0;
}

/* 主要内容区域 */
.hero {
    background: linear-gradient(rgba(0, 0, 0, 0.4), rgba(0, 0, 0, 0.4)), url('首页大图.png') center/cover no-repeat;
    color: white;
    padding: 150px 0;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-content {
    max-width: 800px;
}

.hero h1 {
    font-size: 48px;
    margin-bottom: 20px;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
    letter-spacing: 1px;
}

.btn {
    display: inline-block;
    background-color: #2c5aa0;
    color: white;
    padding: 12px 30px;
    border-radius: 30px;
    font-weight: 600;
    transition: all 0.3s;
    margin-top: 20px;
}

.btn:hover {
    background-color: #1e3d6f;
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

/* 课题组简介部分 */
.intro {
    padding: 80px 0;
    background-color: white;
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title h2 {
    font-size: 32px;
    color: #2c5aa0;
    margin-bottom: 15px;
    position: relative;
    display: inline-block;
}

.section-title h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: #2c5aa0;
}

.intro-content {
    display: flex;
    align-items: center;
    gap: 40px;
}

.intro-text {
    flex: 1;
}

.intro-text p {
    margin-bottom: 20px;
    text-align: justify;
    font-size: 16px;
}

.intro-image {
    flex: 1;
    height: 300px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

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

.highlight {
    background-color: #f0f5ff;
    padding: 20px;
    border-radius: 8px;
    margin-top: 20px;
    border-left: 4px solid #2c5aa0;
}

.highlight p {
    margin-bottom: 0;
}

/* 新闻动态部分 */
.news {
    padding: 80px 0;
    background-color: #f8f9fa;
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.news-card {
    background-color: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s;
}

.news-card:hover {
    transform: translateY(-5px);
}

.news-img {
    height: 180px;
    background-color: #ddd;
    background-size: cover;
    background-position: center;
}

.news-content {
    padding: 20px;
}

.news-date {
    color: #888;
    font-size: 14px;
    margin-bottom: 10px;
}

.news-content h3 {
    margin-bottom: 10px;
    font-size: 18px;
    color: #2c5aa0;
}

.news-content p {
    color: #666;
    font-size: 14px;
    margin-bottom: 15px;
}

.read-more-container {
    text-align: center;
}

.read-more {
    color: #2c5aa0;
    font-weight: 500;
    font-size: 16px;
    display: inline-block;
    padding: 10px 20px;
    border: 2px solid #2c5aa0;
    border-radius: 30px;
    transition: all 0.3s;
}

.read-more:hover {
    background-color: #2c5aa0;
    color: white;
}

/* 页脚样式 */
footer {
    background-color: #2c3e50;
    color: white;
    padding: 50px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-column h3 {
    font-size: 18px;
    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: #3a7bd5;
}

.footer-column p, .footer-column a {
    color: #bdc3c7;
    margin-bottom: 10px;
    display: block;
    transition: color 0.3s;
}

.footer-column a:hover {
    color: white;
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: #bdc3c7;
    font-size: 14px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        text-align: center;
    }
    
    .logo {
        margin-bottom: 15px;
    }
    
    nav ul {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    nav li {
        margin: 0 10px;
    }
    
    .hero h1 {
        font-size: 36px;
    }
    
    .intro-content {
        flex-direction: column;
    }
    
    .intro-image {
        width: 100%;
    }
}

/* 在原有styles.css基础上添加以下样式 */

/* 首页特有样式优化 */
.hero h1 {
    font-size: 48px;
    margin-bottom: 20px;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
    letter-spacing: 1px;
    white-space: nowrap;
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 36px;
        white-space: normal;
        line-height: 1.2;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 28px;
    }
}
/* 在原有styles.css的新闻部分添加图片样式 */
.news-card .news-img {
    height: 180px;
    background-color: #ddd;
    background-size: cover;
    background-position: center;
    overflow: hidden;
}

.news-card .news-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.news-card:hover .news-img img {
    transform: scale(1.05);
}