/* ============================================
   help.css - 帮助中心样式
   使用页面：templates/help/index.html
   ============================================ */

/* ═══════════════════════════════════════════════
   帮助页面主容器
   ═══════════════════════════════════════════════ */
.help-page {
    max-width: 1200px;
    margin: 0 auto;
}

/* ═══════════════════════════════════════════════
   置顶精选文章卡片区
   ═══════════════════════════════════════════════ */
.help-pinned-section {
    margin-bottom: 28px;
}

.help-pinned-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 16px;
}

.help-pinned-card {
    display: flex;
    flex-direction: column;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg, 12px);
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    transition: border-color 0.2s, box-shadow 0.2s, transform 0.15s;
}

.help-pinned-card:hover {
    border-color: var(--color-primary);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    transform: translateY(-2px);
}

.help-pinned-cover {
    width: 100%;
    height: 130px;
    object-fit: cover;
    background: var(--color-bg-tertiary);
}

.help-pinned-cover-placeholder {
    width: 100%;
    height: 130px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--color-bg-tertiary), var(--color-bg-secondary));
    color: var(--color-text-quaternary);
    font-size: 32px;
}

.help-pinned-body {
    padding: 12px 14px 14px;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.help-pinned-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-text-primary);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    margin: 0;
}

.help-pinned-desc {
    font-size: 12px;
    color: var(--color-text-tertiary);
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    margin: 0;
}

.help-pinned-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: auto;
}

.help-pinned-category {
    font-size: 11px;
    padding: 2px 8px;
    border-radius: 4px;
    background: var(--color-bg-tertiary);
    color: var(--color-text-secondary);
}

.help-pinned-stats {
    display: flex;
    gap: 8px;
    font-size: 11px;
    color: var(--color-text-quaternary);
}

.help-pinned-stats span {
    display: inline-flex;
    align-items: center;
    gap: 2px;
}

/* ═══════════════════════════════════════════════
   主体：左侧分类树 + 右侧文章列表
   ═══════════════════════════════════════════════ */
.help-main-layout {
    display: flex;
    gap: 24px;
    align-items: flex-start;
}

/* ─── 左侧分类导航树 ─── */
.help-category-tree {
    width: 140px;
    flex-shrink: 0;
    position: sticky;
    top: 16px;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
    padding: 0;
}

.help-tree-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 14px 16px 10px;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text-secondary);
    border-bottom: 1px solid var(--color-border);
    user-select: none;
}

.help-tree-header i {
    font-size: 15px;
}

.help-tree-nav {
    padding: 8px 0;
}

/* 导航项 */
.help-tree-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    font-size: 13px;
    color: var(--color-text-secondary);
    text-decoration: none;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
    position: relative;
    border-left: 3px solid transparent;
}

.help-tree-item:hover {
    color: var(--color-text-primary);
}

.help-tree-item.active {
    color: var(--color-primary);
    font-weight: 600;
}

.help-tree-item i:first-child {
    font-size: 14px;
    width: 16px;
    text-align: center;
    flex-shrink: 0;
}

/* 可展开分类的箭头图标（左侧） */
.help-tree-toggle {
    transition: transform 0.25s;
    color: var(--color-text-quaternary);
}

/* 子分类容器 */
.help-tree-children {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease;
}

.help-tree-group.expanded > .help-tree-children {
    max-height: 500px;
}

.help-tree-group.expanded > a > .help-tree-toggle {
    transform: rotate(180deg);
}

/* 子分类项（第二级） */
.help-tree-child {
    padding-left: 34px;
    font-size: 12px;
}

/* 孙分类项（第三级） */
.help-tree-grandchild {
    padding-left: 50px;
    font-size: 12px;
}

/* 嵌套子组 */
.help-tree-subgroup {
    margin: 0;
}

/* ─── 右侧文章列表区 ─── */
.help-article-area {
    flex: 1;
    min-width: 0;
}

/* ═══════════════════════════════════════════════
   文章列表项样式（复用 category.html 风格）
   ═══════════════════════════════════════════════ */
.help-list-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 14px 16px;
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md, 8px);
    margin-bottom: 8px;
    text-decoration: none;
    color: inherit;
    transition: border-color 0.2s, background 0.15s;
}

.help-list-item:hover {
    border-color: var(--color-primary);
    background: var(--color-bg-tertiary);
}

.help-list-cover {
    width: 80px;
    height: 56px;
    border-radius: 6px;
    object-fit: cover;
    flex-shrink: 0;
    background: var(--color-bg-tertiary);
}

.help-list-cover-placeholder {
    width: 80px;
    height: 56px;
    border-radius: 6px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-bg-tertiary);
    color: var(--color-text-quaternary);
    font-size: 22px;
}

.help-list-body {
    flex: 1;
    min-width: 0;
}

.help-list-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-text-primary);
    line-height: 1.4;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin: 0 0 4px 0;
}

.help-list-pinned {
    color: var(--color-primary);
    margin-right: 4px;
    font-size: 12px;
}

.help-list-desc {
    font-size: 12px;
    color: var(--color-text-tertiary);
    line-height: 1.4;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.help-list-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
}

.help-list-category {
    font-size: 11px;
    padding: 2px 8px;
    border-radius: 4px;
    background: var(--color-bg-tertiary);
    color: var(--color-text-secondary);
    white-space: nowrap;
}

.help-list-stats {
    display: flex;
    gap: 8px;
    font-size: 11px;
    color: var(--color-text-quaternary);
    white-space: nowrap;
}

.help-list-stats span {
    display: inline-flex;
    align-items: center;
    gap: 2px;
}

.help-list-date {
    font-size: 11px;
    color: var(--color-text-quaternary);
    white-space: nowrap;
}

/* ═══════════════════════════════════════════════
   响应式适配
   ═══════════════════════════════════════════════ */

/* 中屏：分类树缩窄 */
@media (max-width: 1024px) {
    .help-category-tree {
        width: 140px;
    }

    .help-pinned-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
}

/* 小屏：分类树折叠为可展开面板 */
@media (max-width: 768px) {
    .help-page {
        overflow: hidden;
    }

    .help-main-layout {
        flex-direction: column;
        gap: 0;
    }

    .help-article-area {
        width: 100%;
        overflow: hidden;
    }

    .help-category-tree {
        width: 100%;
        position: static;
        max-height: none;
        border-radius: var(--radius-md, 8px);
        margin-bottom: 16px;
    }

    .help-tree-header {
        cursor: pointer;
        border-bottom: none;
        padding: 12px 16px;
    }

    .help-tree-header::after {
        content: '\ea4e'; /* ri-arrow-down-s-line */
        font-family: 'remixicon';
        margin-left: auto;
        font-size: 16px;
        color: var(--color-text-quaternary);
        transition: transform 0.2s;
    }

    .help-category-tree.mobile-open .help-tree-header::after {
        transform: rotate(180deg);
    }

    .help-tree-nav {
        display: none;
    }

    .help-category-tree.mobile-open .help-tree-nav {
        display: block;
    }

    .help-category-tree.mobile-open .help-tree-header {
        border-bottom: 1px solid var(--color-border);
    }

    .help-pinned-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
        gap: 12px;
    }

    .help-pinned-cover,
    .help-pinned-cover-placeholder {
        height: 100px;
    }

    /* 列表项紧凑化 */
    .help-list-item {
        padding: 12px;
        gap: 12px;
    }

    .help-list-cover,
    .help-list-cover-placeholder {
        width: 60px;
        height: 42px;
    }

    .help-list-meta {
        display: none;
    }
}