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

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --background-color: #f1f5f9;
    --surface-color: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --sidebar-width: 260px;
    --header-height: 64px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

/* 登录页面样式 */
.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    position: relative;
    overflow: hidden;
}

.login-page::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 50%);
    animation: rotate 30s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.login-container {
    position: relative;
    width: 100%;
    max-width: 420px;
    background: var(--surface-color);
    padding: 48px 40px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    z-index: 1;
}

.login-header {
    text-align: center;
    margin-bottom: 36px;
}

.login-header h1 {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.login-header p {
    color: var(--text-secondary);
    font-size: 14px;
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    font-size: 14px;
    color: var(--text-primary);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 15px;
    transition: all 0.2s;
    background: var(--surface-color);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border: none;
    border-radius: var(--radius-md);
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
    font-family: inherit;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--surface-color);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--background-color);
    border-color: var(--secondary-color);
}

.btn-success {
    background: var(--success-color);
    color: white;
}

.btn-success:hover {
    background: #059669;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-danger {
    background: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background: #dc2626;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 14px;
}

.btn-block {
    width: 100%;
}

/* 管理后台布局 */
.admin-layout {
    display: flex;
    min-height: 100vh;
}

/* 侧边栏 */
.sidebar {
    width: var(--sidebar-width);
    background: var(--surface-color);
    border-right: 1px solid var(--border-color);
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    display: flex;
    flex-direction: column;
    z-index: 100;
}

.sidebar-header {
    padding: 24px 20px;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-brand {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 12px;
}

.sidebar-menu {
    flex: 1;
    padding: 16px 12px;
    overflow-y: auto;
}

.menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    margin-bottom: 4px;
    transition: all 0.2s;
}

.menu-item:hover {
    background: var(--background-color);
    color: var(--text-primary);
}

.menu-item.active {
    background: var(--primary-color);
    color: white;
}

.sidebar-footer {
    padding: 16px;
    border-top: 1px solid var(--border-color);
}

/* 主内容区 */
.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    min-height: 100vh;
}

/* 顶部导航栏 */
.header {
    height: var(--header-height);
    background: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 32px;
    position: sticky;
    top: 0;
    z-index: 50;
}

.header-left h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
}

.header-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 8px 16px;
    background: var(--background-color);
    border-radius: var(--radius-md);
}

.user-avatar {
    width: 36px;
    height: 36px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
}

/* 内容区域 */
.content {
    padding: 32px;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 32px;
}

.page-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-primary);
}

/* 卡片样式 */
.card {
    background: var(--surface-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.card-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
}

.card-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
}

.card-body {
    padding: 24px;
}

/* 统计卡片 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
    margin-bottom: 32px;
}

.stat-card {
    background: var(--surface-color);
    padding: 24px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 16px;
    transition: all 0.2s;
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.stat-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
}

.stat-icon.blue { background: rgba(37, 99, 235, 0.1); color: var(--primary-color); }
.stat-icon.green { background: rgba(16, 185, 129, 0.1); color: var(--success-color); }
.stat-icon.orange { background: rgba(245, 158, 11, 0.1); color: var(--warning-color); }

.stat-info {
    flex: 1;
}

.stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
}

.stat-label {
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* 筛选区域 */
.filter-section {
    background: var(--surface-color);
    padding: 24px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    margin-bottom: 24px;
}

.filter-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 16px;
}

.filter-actions {
    display: flex;
    gap: 12px;
}

/* 表格样式 */
.table-container {
    background: var(--surface-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.table {
    width: 100%;
    border-collapse: collapse;
}

.table thead {
    background: var(--background-color);
}

.table th {
    padding: 14px 16px;
    text-align: left;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-bottom: 1px solid var(--border-color);
}

.table td {
    padding: 16px;
    font-size: 14px;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border-color);
}

.table tbody tr {
    transition: background 0.2s;
}

.table tbody tr:hover {
    background: var(--background-color);
}

.table-actions {
    display: flex;
    gap: 8px;
}

/* 模态框 */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--surface-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    width: 90%;
    max-width: 600px;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.9);
    transition: transform 0.3s;
}

.modal-overlay.active .modal {
    transform: scale(1);
}

.modal-header {
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-title {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
}

.modal-close {
    width: 36px;
    height: 36px;
    border: none;
    background: var(--background-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.modal-close:hover {
    background: var(--border-color);
}

.modal-body {
    padding: 24px;
}

.modal-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: flex-end;
    gap: 12px;
}

/* 表单网格 */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
}

/* 提示消息 */
.alert {
    padding: 16px 20px;
    border-radius: var(--radius-md);
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    color: #065f46;
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.alert-error {
    background: rgba(239, 68, 68, 0.1);
    color: #991b1b;
    border: 1px solid rgba(239, 68, 68, 0.3);
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s;
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
}

@media (max-width: 768px) {
    .content {
        padding: 20px;
    }
    
    .page-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
    }
    
    .page-title {
        font-size: 24px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .form-grid {
        grid-template-columns: 1fr;
    }
    
    .header {
        padding: 0 20px;
    }
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid var(--background-color);
    border-top: 2px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 60px 24px;
    color: var(--text-secondary);
}

.empty-state-icon {
    font-size: 64px;
    margin-bottom: 16px;
    opacity: 0.5;
}

.empty-state-text {
    font-size: 16px;
    margin-bottom: 8px;
}

.empty-state-desc {
    font-size: 14px;
}