/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Microsoft YaHei', Arial, sans-serif;
}

body {
    background-color: #f5f7fa;
    color: #333;
    line-height: 1.6;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* 导航栏样式 - 修改颜色和字体大小 */
header {
    background-color: #3f51b5; /* 改为3f51b5颜色 */
    color: #fff;
    padding: 15px 0; /* 恢复适当的内边距 */
    text-align: center;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 2rem; /* 增加3号字体大小 */
    font-weight: bold;
    color: white;
}

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

.nav-links li {
    margin-left: 2rem; /* 增加间距以适应更大的字体 */
}

.nav-links a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
    padding: 0.8rem 0; /* 增加内边距以适应更大的字体 */
    font-size: 1.3rem; /* 增加3号字体大小 */
    font-weight: 500;
}

.nav-links a:hover, .nav-links a.active {
    color: #c5cae9; /* 调整悬停颜色以匹配新主题 */
    border-bottom: 2px solid #c5cae9; /* 添加下划线效果 */
}

/* 主要内容区域 */
main {
    padding: 2rem 0;
    min-height: calc(100vh - 200px);
    margin-top: 80px; /* 为固定导航栏留出空间 */
}

.page-header {
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid #3498db;
}

/* 主页样式 */
.hero {
    background: linear-gradient(135deg, #3498db, #2c3e50);
    color: white;
    padding: 3rem 0;
    text-align: center;
    border-radius: 5px;
    margin-bottom: 2rem;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.news-section, .research-section {
    background: white;
    padding: 1.5rem;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    margin-bottom: 2rem;
}

.news-section ul, .research-section ul {
    padding-left: 1.5rem;
}

.news-section li, .research-section li {
    margin-bottom: 0.5rem;
}

/* 课题组成员页面样式 */
.members-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1.5rem;
}

.member-card {
    background: white;
    border-radius: 5px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    transition: transform 0.3s;
}

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

.member-img {
    height: 200px;
    background-color: #eee;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #777;
}

.member-info {
    padding: 1rem;
}

.member-info h3 {
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

/* 发表论文页面样式 */
.publication-list {
    background: white;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    overflow: hidden;
}

.publication-item {
    padding: 1.5rem;
    border-bottom: 1px solid #eee;
}

.publication-item:last-child {
    border-bottom: none;
}

.publication-title {
    font-weight: bold;
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

.publication-authors {
    color: #666;
    margin-bottom: 0.5rem;
}

.publication-journal {
    color: #3498db;
    font-style: italic;
}

/* 资料下载页面样式 */
.downloads-list {
    background: white;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    overflow: hidden;
}

.download-item {
    padding: 1.5rem;
    border-bottom: 1px solid #eee;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.download-item:last-child {
    border-bottom: none;
}

.download-info h3 {
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

.download-btn {
    background: #3498db;
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 3px;
    cursor: pointer;
    transition: background 0.3s;
    text-decoration: none;
    display: inline-block;
}

.download-btn:hover {
    background: #2980b9;
}

/* 联系我们页面样式 */
.contact-info {
    background: white;
    padding: 1.5rem;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    margin-bottom: 2rem;
}

.contact-info h3 {
    margin-bottom: 1rem;
    color: #2c3e50;
}

.contact-info p {
    margin-bottom: 0.5rem;
}

.contact-form {
    background: white;
    padding: 1.5rem;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.contact-form h3 {
    margin-bottom: 1rem;
    color: #2c3e50;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: bold;
}

.form-group input, .form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: 3px;
    font-size: 1rem;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.submit-btn {
    background: #3498db;
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 3px;
    cursor: pointer;
    transition: background 0.3s;
    font-size: 1rem;
}

.submit-btn:hover {
    background: #2980b9;
}

/* 页脚样式 */
footer {
    background: #2c3e50;
    color: white;
    padding: 2rem 0;
    text-align: center;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
    }
    
    .nav-links {
        margin-top: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .nav-links li {
        margin: 0.5rem;
    }
    
    .nav-links a {
        font-size: 1.1rem; /* 移动端适当减小字体 */
    }
    
    .logo {
        font-size: 1.7rem; /* 移动端适当减小字体 */
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .download-item {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .download-btn {
        margin-top: 1rem;
        align-self: flex-end;
    }
    
    main {
        margin-top: 120px; /* 移动端增加顶部间距 */
    }
}