/* 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 */
header {
    background-color: #2c3e50;
    color: white;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: bold;
}

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

.nav-links li {
    margin-left: 1.5rem;
}

.nav-links a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
    padding: 0.5rem 0;
}

.nav-links a:hover, .nav-links a.active {
    color: #3498db;
}

/* 主要内容区域 */
main {
    padding: 2rem 0;
    min-height: calc(100vh - 200px);
}

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

/* 课题组成员页面样式 - 每行最多四张卡片 */
.members-grid {
    display: grid;
    grid-template-columns: repeat(4, 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;
    overflow: hidden;
}

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

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

.member-info {
    padding: 1.2rem;
}

.member-info h3 {
    margin-bottom: 0.5rem;
    color: #2c3e50;
    font-size: 1.1rem;
}

.member-info p {
    margin-bottom: 0.4rem;
    font-size: 0.9rem;
}

/* 已毕业学生样式 */
.research-section {
    background: white;
    padding: 1.5rem;
    border-radius: 5px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    margin-top: 2rem;
}

.research-section h3 {
    margin-bottom: 1rem;
    color: #2c3e50;
}

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

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

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

/* 响应式设计 */
@media (max-width: 1200px) {
    .members-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 900px) {
    .members-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {
    .members-grid {
        grid-template-columns: 1fr;
    }
    
    .navbar {
        flex-direction: column;
    }
    
    .nav-links {
        margin-top: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .nav-links li {
        margin: 0.5rem;
    }
}