/* ============================================================
   律伴AI自习室 — 全局公共样式
   风格：现代简约 + 卡片化
   规范：
     1. 颜色变量全部用 CSS 变量（如需换主题，在 :root 改一处即可）
     2. 通用组件命名 .app-*  前缀，避免与 Bootstrap 冲突
     3. 页面专属样式放 static/css/pages/xxx.css，不写到这里
   ============================================================ */

:root {
    /* 主色系（律伴品牌：深蓝 + 暖橙辅色） */
    --lvban-primary: #0d6efd;
    --lvban-primary-hover: #0b5ed7;
    --lvban-secondary: #6c757d;
    --lvban-success: #198754;
    --lvban-danger: #dc3545;
    --lvban-warning: #ffc107;
    --lvban-info: #0dcaf0;

    /* 中性色 */
    --lvban-bg: #f5f7fa;
    --lvban-card-bg: #ffffff;
    --lvban-border: #e5e7eb;
    --lvban-text: #1f2937;
    --lvban-text-muted: #6b7280;

    /* 圆角 */
    --lvban-radius-sm: 6px;
    --lvban-radius: 10px;
    --lvban-radius-lg: 14px;

    /* 阴影 */
    --lvban-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --lvban-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    --lvban-shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08);
}

/* ==================== 基础重置 ==================== */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
                 "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    background: var(--lvban-bg);
    color: var(--lvban-text);
    margin: 0;
}

/* ==================== 顶部栏 ==================== */
.app-header {
    height: 60px;
    box-shadow: var(--lvban-shadow);
}

.app-version {
    font-size: 11px;
    font-weight: 600;
}

.app-user-info {
    font-size: 14px;
}

/* ==================== 整体布局 ==================== */
.app-layout {
    display: flex;
    min-height: calc(100vh - 60px);
}

/* ==================== 侧边栏 ==================== */
.app-sidebar {
    width: 220px;
    background: #fff;
    border-right: 1px solid var(--lvban-border);
    padding: 16px 0;
    flex-shrink: 0;
    position: sticky;
    top: 60px;
    height: calc(100vh - 60px);
    overflow-y: auto;
}

.sidebar-section {
    padding: 0 12px;
}

.sidebar-title {
    font-size: 12px;
    color: var(--lvban-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 8px 12px 12px;
    font-weight: 600;
}

.app-sidebar .nav-link {
    border-radius: var(--lvban-radius-sm);
    margin: 2px 0;
    padding: 10px 14px;
    color: var(--lvban-text);
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: background 0.15s, color 0.15s;
}

.app-sidebar .nav-link i {
    font-size: 18px;
    width: 20px;
    text-align: center;
}

.app-sidebar .nav-link:hover {
    background: #f0f4f8;
    color: var(--lvban-primary);
}

.app-sidebar .nav-link.active {
    background: var(--lvban-primary);
    color: #fff;
    font-weight: 500;
}

/* ==================== 主内容区 ==================== */
.app-main {
    flex: 1;
    min-width: 0;        /* 防止 flex 子元素溢出 */
    padding: 24px;
    overflow-x: auto;
}

/* ==================== 页脚 — 备案信息（合规展示） ==================== */
.app-footer {
    /* 顶部分隔线，与主内容区分隔 */
    border-top: 1px solid #e9ecef;
    background: #fafbfc;
    padding: 14px 24px;
    text-align: center;
    font-size: 12px;
    color: #6c757d;
    /* 防止页脚被侧边栏或主内容 flex 撑大 */
    flex-shrink: 0;
}
.app-footer-content {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px 24px;     /* 行间距 12px，列间距 24px */
    margin-bottom: 4px;
}
.app-footer-item {
    display: inline-flex;
    align-items: center;
    gap: 4px;
}
.app-footer-item i {
    font-size: 13px;
    color: #6c757d;
}
.app-footer-item a {
    color: #6c757d;
    text-decoration: none;
    transition: color 0.15s;
}
.app-footer-item a:hover {
    color: #0d6efd;
    text-decoration: underline;
}
.app-footer-copyright {
    color: #adb5bd;
    font-size: 11px;
    margin-top: 4px;
}

/* 移动端页脚更紧凑 */
@media (max-width: 576px) {
    .app-footer {
        padding: 10px 12px;
        font-size: 11px;
    }
    .app-footer-content {
        gap: 6px 14px;
    }
}

/* ==================== 页面通用组件 ==================== */
/* 页面标题 */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 12px;
}

.page-title {
    font-size: 22px;
    font-weight: 600;
    margin: 0;
    color: var(--lvban-text);
}

.page-subtitle {
    color: var(--lvban-text-muted);
    font-size: 13px;
    margin-top: 4px;
}

/* 卡片 */
.lvban-card {
    background: var(--lvban-card-bg);
    border-radius: var(--lvban-radius);
    box-shadow: var(--lvban-shadow);
    padding: 20px;
    margin-bottom: 16px;
}

.lvban-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 16px;
    margin-bottom: 16px;
    border-bottom: 1px solid var(--lvban-border);
}

.lvban-card-title {
    font-size: 16px;
    font-weight: 600;
    margin: 0;
}

/* 表格（卡片化） */
.lvban-table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    font-size: 14px;
}

.lvban-table thead th {
    background: #f9fafb;
    color: var(--lvban-text-muted);
    font-weight: 500;
    font-size: 13px;
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid var(--lvban-border);
}

.lvban-table thead th:first-child {
    border-top-left-radius: var(--lvban-radius-sm);
}

.lvban-table thead th:last-child {
    border-top-right-radius: var(--lvban-radius-sm);
}

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

.lvban-table tbody tr:hover {
    background: #f9fafb;
}

.lvban-table tbody tr:last-child td {
    border-bottom: none;
}

/* 工具栏（搜索 + 按钮） */
.lvban-toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}

.lvban-toolbar .lvban-search {
    flex: 1;
    max-width: 320px;
    position: relative;
}

.lvban-toolbar .lvban-search input {
    padding-left: 36px;
    border-radius: var(--lvban-radius-sm);
}

.lvban-toolbar .lvban-search i {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--lvban-text-muted);
    font-size: 14px;
}

/* 分页 */
.lvban-pagination {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 0 4px;
    flex-wrap: wrap;
    gap: 8px;
}

.lvban-pagination .pagination-info {
    color: var(--lvban-text-muted);
    font-size: 13px;
}

.lvban-pagination .pagination {
    margin: 0;
}

.lvban-pagination .page-link {
    border-radius: var(--lvban-radius-sm);
    margin: 0 2px;
    color: var(--lvban-text);
    border-color: var(--lvban-border);
}

.lvban-pagination .page-item.active .page-link {
    background: var(--lvban-primary);
    border-color: var(--lvban-primary);
}

/* 状态徽章 */
.lvban-badge {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
    line-height: 1.5;
}

.lvban-badge-success { background: #d1fae5; color: #065f46; }
.lvban-badge-danger  { background: #fee2e2; color: #991b1b; }
.lvban-badge-warning { background: #fef3c7; color: #92400e; }
.lvban-badge-info    { background: #dbeafe; color: #1e40af; }
.lvban-badge-secondary { background: #e5e7eb; color: #4b5563; }

/* 加载占位 */
.lvban-loading {
    text-align: center;
    padding: 60px 20px;
    color: var(--lvban-text-muted);
}

.lvban-loading .spinner-border {
    margin-bottom: 12px;
}

.lvban-empty {
    text-align: center;
    padding: 60px 20px;
    color: var(--lvban-text-muted);
}

.lvban-empty i {
    font-size: 48px;
    margin-bottom: 12px;
    color: #d1d5db;
}

/* ==================== 底部导航（移动端） ==================== */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 60px;
    background: #fff;
    border-top: 1px solid var(--lvban-border);
    display: flex;
    justify-content: space-around;
    align-items: center;
    z-index: 1000;
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.04);
}

.bottom-nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    color: var(--lvban-text-muted);
    font-size: 11px;
    padding: 6px 8px;
    flex: 1;
    gap: 2px;
}

.bottom-nav-item i {
    font-size: 20px;
}

.bottom-nav-item.active {
    color: var(--lvban-primary);
}

@media (max-width: 991.98px) {
    body { padding-bottom: 70px; }
    .app-main { padding: 16px; }
}

/* ==================== toast 容器 ==================== */
.toast-container {
    position: fixed;
    top: 76px;
    right: 16px;
    z-index: 9999;
    min-width: 280px;
    max-width: 400px;
}

.toast-container .alert {
    margin-bottom: 8px;
    box-shadow: var(--lvban-shadow-lg);
    border: none;
    border-radius: var(--lvban-radius);
}

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
    .page-title { font-size: 18px; }
    .lvban-card { padding: 16px; }
    .lvban-table { font-size: 13px; }
    .lvban-table thead th,
    .lvban-table tbody td { padding: 10px 8px; }
}