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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

.container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* 导航栏 */
.navbar {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 2rem;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.nav-menu a:hover,
.nav-menu a.active {
    background-color: rgba(255,255,255,0.2);
}

/* 主内容区 */
.main-content {
    flex: 1;
    padding: 2rem;
    max-width: 1400px;
    width: 100%;
    margin: 0 auto;
}

/* 页头 */
.page-header {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    margin-bottom: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.page-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #333;
}

/* 卡片 */
.card {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.card-header {
    border-bottom: 1px solid #eee;
    padding-bottom: 1rem;
    margin-bottom: 1rem;
    font-size: 1.2rem;
    font-weight: 600;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 0.6rem 1.2rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    text-decoration: none;
    transition: all 0.3s;
    text-align: center;
}

.btn-primary {
    background: #667eea;
    color: white;
}

.btn-primary:hover {
    background: #5568d3;
}

.btn-success {
    background: #28a745;
    color: white;
}

.btn-success:hover {
    background: #218838;
}

.btn-danger {
    background: #dc3545;
    color: white;
}

.btn-danger:hover {
    background: #c82333;
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
}

.btn-sm {
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
}

/* 表格 */
.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: white;
}

table th,
table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #eee;
}

table th {
    background: #f8f9fa;
    font-weight: 600;
    color: #495057;
}

table tr:hover {
    background: #f8f9fa;
}

/* 表单 */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #495057;
}

.form-control {
    width: 100%;
    padding: 0.6rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 0.9rem;
    transition: border-color 0.3s;
}

.form-control:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

textarea.form-control {
    resize: vertical;
    min-height: 100px;
}

select.form-control {
    cursor: pointer;
}

/* 统计卡片 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    border-left: 4px solid #667eea;
}

.stat-card h3 {
    font-size: 0.9rem;
    color: #6c757d;
    margin-bottom: 0.5rem;
}

.stat-card .stat-value {
    font-size: 2rem;
    font-weight: bold;
    color: #333;
}

/* 分页 */
.pagination {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 2rem;
}

.pagination a,
.pagination span {
    padding: 0.5rem 1rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    text-decoration: none;
    color: #667eea;
}

.pagination a:hover {
    background: #f8f9fa;
}

.pagination .current {
    background: #667eea;
    color: white;
    border-color: #667eea;
}

/* 消息提示 */
.alert {
    padding: 1rem;
    border-radius: 4px;
    margin-bottom: 1rem;
}

.alert-success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-info {
    background: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* 加载动画 */
.loading {
    text-align: center;
    padding: 2rem;
    color: #6c757d;
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 3rem;
    color: #6c757d;
}

.empty-state svg {
    width: 64px;
    height: 64px;
    margin-bottom: 1rem;
    opacity: 0.5;
}

/* 页脚 */
.footer {
    background: white;
    padding: 1.5rem;
    text-align: center;
    color: #6c757d;
    border-top: 1px solid #eee;
    margin-top: 2rem;
}

/* 进度条 */
.progress {
    width: 100%;
    background-color: #e9ecef;
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: #667eea;
    color: white;
    text-align: center;
    line-height: 20px;
    font-size: 12px;
    transition: width 0.3s ease;
    border-radius: 4px;
}

/* 响应式 */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-menu {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .main-content {
        padding: 1rem;
    }
    
    .page-header {
        flex-direction: column;
        gap: 1rem;
        align-items: flex-start;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
}