/**
 * Sidebar Layout - History Detail 统一侧边栏
 *
 * 职责：提供集成了 TOC 和 Dock 数据的统一侧边栏布局
 * 依赖：01-foundation/variables.css
 * 设计：High-end Minimalist (Ultra-light & Clean)
 */

/* ==================== App Shell 容器 ==================== */

.app-shell {
  display: flex;
  height: 100vh;
  overflow: hidden;
  background-color: var(--color-bg-base);
}

/* ==================== 侧边栏主体 ==================== */

.app-sidebar {
  width: var(--sidebar-width);
  background-color: var(--color-bg-secondary); /* Use the lighter secondary bg */
  border-right: 1px solid var(--color-border-light);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;

  /* Mobile defaults: fixed off-screen */
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  z-index: var(--sidebar-z-index);
  transform: translateX(-100%);
  transition: var(--sidebar-transition);
}

/* 移动端打开状态 */
.app-sidebar.mobile-open {
  transform: translateX(0);
  box-shadow: var(--shadow-xl); /* Use variable */
}

/* 桌面端样式 */
@media (min-width: 768px) {
  .app-sidebar {
    position: static;
    transform: none;
  }

  /* 收起状态 */
  .app-sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
  }

  .app-sidebar.collapsed .px-6 {
    padding-left: 0;
    padding-right: 0;
  }

  /* 收起时头部垂直排列并居中 */
  .app-sidebar.collapsed .sidebar-header {
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    padding-top: 1.5rem;
    padding-bottom: 1rem;
  }

  .app-sidebar.collapsed .sidebar-logo {
    width: 32px;
    height: 32px;
    object-fit: contain;
  }

  /* 隐藏文字元素 */
  .app-sidebar.collapsed .nav-text,
  .app-sidebar.collapsed .nav-section-title,
  .app-sidebar.collapsed .sidebar-section-title span,
  .app-sidebar.collapsed .sidebar-section-chevron,
  .app-sidebar.collapsed .sidebar-section-content,
  .app-sidebar.collapsed .sidebar-footer,
  .app-sidebar.collapsed .sidebar-footer-compact,
  .app-sidebar.collapsed .sidebar-divider {
    opacity: 0;
    pointer-events: none;
    display: none;
  }

  /* 导航项居中 */
  .app-sidebar.collapsed .nav-item {
    justify-content: center;
    padding-left: 0;
    padding-right: 0;
  }

  /* Section header 居中 */
  .app-sidebar.collapsed .sidebar-section-header {
    justify-content: center;
    padding-left: 0;
    padding-right: 0;
  }

  .app-sidebar.collapsed .nav-icon {
    margin-right: 0;
  }
}

/* ==================== 侧边栏头部 ==================== */

.sidebar-header {
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: var(--sidebar-transition);
  border-bottom: 1px solid var(--color-border-light);
  background-color: var(--color-bg-secondary); /* Consistent with sidebar bg */
}

.sidebar-logo {
  height: 2rem;
  transition: var(--sidebar-transition);
}

.sidebar-toggle-btn {
  display: none; /* 仅桌面端显示 */
  padding: 0.375rem;
  color: var(--color-text-muted);
  background: transparent;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition-fast);
}

.sidebar-toggle-btn:hover {
  color: var(--color-text-primary);
  background: var(--slate-200);
}

@media (min-width: 768px) {
  .sidebar-toggle-btn {
    display: flex;
    align-items: center;
    justify-content: center;
  }
}

/* 移动端关闭按钮 */
.sidebar-close-btn {
  display: flex;
  padding: 0.5rem;
  color: var(--color-text-muted);
  background: transparent;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: var(--transition-fast);
}

.sidebar-close-btn:hover {
  color: var(--color-text-primary);
  background: var(--slate-200);
}

@media (min-width: 768px) {
  .sidebar-close-btn {
    display: none;
  }
}

/* ==================== 侧边栏导航区 ==================== */

.sidebar-nav {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 0.75rem;
  overflow: hidden; /* 不滚动，内部 TOC 内容区滚动 */
}

/* TOC section 占据剩余空间 */
#sidebarTocSection {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 0; /* 关键：允许 flex 子元素缩小 */
  overflow: hidden;
}

/* TOC 内容区可滚动 */
#sidebarTocSection .sidebar-section-content {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
}

/* 自定义滚动条（应用到 TOC 内容区） */
#sidebarTocSection .sidebar-section-content::-webkit-scrollbar {
  width: 4px; /* Thinner scrollbar */
}

#sidebarTocSection .sidebar-section-content::-webkit-scrollbar-track {
  background: transparent;
}

#sidebarTocSection .sidebar-section-content::-webkit-scrollbar-thumb {
  background: var(--slate-300);
  border-radius: var(--radius-sm);
}

#sidebarTocSection .sidebar-section-content::-webkit-scrollbar-thumb:hover {
  background: var(--slate-400);
}

/* ==================== 导航分组标题 ==================== */

.nav-section-title {
  padding: 0 0.75rem;
  margin-bottom: 0.5rem;
  margin-top: 1.5rem; /* Increased top margin */
  font-size: 11px;
  font-weight: 600;
  color: var(--slate-400);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: opacity var(--transition-fast);
}

.nav-section-title:first-child {
  margin-top: 0;
}

/* ==================== 导航项 ==================== */

.nav-item {
  display: flex;
  align-items: center;
  padding: var(--sidebar-nav-item-padding);
  color: var(--slate-600);
  text-decoration: none;
  border-radius: var(--radius-lg);
  transition: all 0.2s ease;
  font-weight: 500;
  font-size: var(--sidebar-nav-item-font-size);
  margin-bottom: 0.25rem;
  user-select: none;
  cursor: pointer;
}

.nav-item:hover {
  background-color: var(--slate-200); /* Slightly darker hover */
  color: var(--slate-900);
}

.nav-item.active {
  background-color: var(--color-bg-base); /* White background for active */
  color: var(--indigo-600);
  font-weight: 600;
  box-shadow: var(--shadow-sm); /* Subtle shadow for active item */
}

.nav-icon {
  margin-right: 0.75rem;
  font-size: 1.25rem;
  color: var(--slate-400);
  transition: color 0.2s ease;
  flex-shrink: 0;
}

.nav-item:hover .nav-icon {
  color: var(--slate-600);
}

.nav-item.active .nav-icon {
  color: var(--indigo-500);
}

.nav-text {
  transition: opacity var(--transition-fast);
}

/* ==================== 可折叠区域 ==================== */

.sidebar-section {
  margin-bottom: 0.25rem;
}

.sidebar-section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: var(--sidebar-section-header-padding);
  color: var(--slate-600);
  background: transparent;
  border: none;
  border-radius: var(--radius-lg);
  font-size: 0.9375rem;
  font-weight: 500;
  text-align: left;
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
}

.sidebar-section-header:hover {
  background-color: var(--slate-200);
  color: var(--slate-900);
}

.sidebar-section-title {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  transition: opacity var(--transition-fast);
}

.sidebar-section-title iconify-icon {
  font-size: 1.25rem;
  color: var(--slate-400);
  transition: color 0.2s ease;
}

.sidebar-section-header:hover .sidebar-section-title iconify-icon {
  color: var(--slate-500);
}

.sidebar-section-chevron {
  font-size: 16px;
  color: var(--slate-400);
  transition: all 0.2s ease;
}

.sidebar-section-header:hover .sidebar-section-chevron {
  color: var(--slate-600);
}

.sidebar-section.expanded .sidebar-section-chevron {
  transform: rotate(90deg);
}

/* 折叠内容区 */
.sidebar-section-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
  padding: var(--sidebar-section-content-padding);
}

.sidebar-section.expanded .sidebar-section-content {
  max-height: none; /* 移除高度限制，由 flex 布局控制 */
}

/* 非 TOC section 的折叠区域保持原有行为 */
.sidebar-section:not(#sidebarTocSection).expanded .sidebar-section-content {
  max-height: 600px; /* 其他折叠区域保持固定高度 */
}

/* ==================== TOC 目录列表（集成到侧边栏） ==================== */

.sidebar-toc-list {
  list-style: none;
  padding: 0 0.5rem;
  margin: 0;
}

.sidebar-toc-item {
  margin-bottom: 2px;
  position: relative;
}

/* 增加左侧连接线效果，更像树状结构 */
.sidebar-toc-item::before {
  content: '';
  position: absolute;
  left: 6px;
  top: 0;
  bottom: 0;
  width: 1px;
  background-color: var(--slate-200);
  display: none; /* 默认隐藏，可选开启 */
}

.sidebar-toc-link {
  display: block;
  padding: 0.5rem 0.75rem;
  color: var(--slate-500);
  text-decoration: none;
  font-weight: 400;
  font-size: 0.875rem; /* 14px */
  transition: all 0.15s ease;
  border-radius: var(--radius-md);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  line-height: 1.4;
}

.sidebar-toc-link:hover {
  background: var(--slate-100);
  color: var(--slate-900);
}

.sidebar-toc-link.active {
  background: var(--color-bg-base);
  color: var(--indigo-600);
  font-weight: 600;
  box-shadow: var(--shadow-sm);
}

/* TOC 层级缩进 - 优化层次感 */
.sidebar-toc-item.toc-h2 .sidebar-toc-link {
  padding-left: 1.25rem; /* 20px */
  font-size: 0.875rem;
}
.sidebar-toc-item.toc-h3 .sidebar-toc-link {
  padding-left: 2rem; /* 32px */
  font-size: 0.8125rem; /* 13px */
  color: var(--slate-400);
}
.sidebar-toc-item.toc-h4 .sidebar-toc-link {
  padding-left: 2.75rem; /* 44px */
  font-size: 0.8125rem;
  color: var(--slate-400);
}
.sidebar-toc-item.toc-h5 .sidebar-toc-link {
  padding-left: 3.5rem;
  font-size: 0.75rem;
}
.sidebar-toc-item.toc-h6 .sidebar-toc-link {
  padding-left: 4.25rem;
  font-size: 0.75rem;
}

/* ==================== Dock 统计信息（集成到侧边栏） ==================== */

.sidebar-stat-list {
  padding: 0 0.5rem;
}

.sidebar-stat-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.5rem 0.375rem;
  font-size: var(--font-size-xs);
  color: var(--color-text-secondary);
  border-bottom: 1px solid var(--color-border-light);
}

.sidebar-stat-item:last-child {
  border-bottom: none;
}

.sidebar-stat-label {
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
}

.sidebar-stat-value {
  font-weight: var(--font-weight-semibold);
  color: var(--color-primary);
  background: var(--indigo-50);
  padding: 2px 6px;
  border-radius: 4px;
}

/* ==================== 侧边栏底部 ==================== */

.sidebar-footer {
  padding: 0.75rem;
  border-top: 1px solid var(--color-border-light);
  transition: opacity var(--transition-fast);
}

/* 紧凑底部布局（阅读进度 + 快速统计 + 设置） */
.sidebar-footer-compact {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem; /* Increased padding */
  border-top: 1px solid var(--color-border-light);
  font-size: 0.75rem;
  transition: opacity var(--transition-fast);
  background-color: var(--color-bg-secondary);
}

.sidebar-progress {
  color: var(--indigo-600); /* Use primary color for progress */
  font-weight: 600;
  font-size: 0.8125rem;
  white-space: nowrap;
  flex-shrink: 0;
}

.sidebar-quick-stats {
  flex: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  color: var(--slate-400);
  align-items: center;
}

.sidebar-quick-stat {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
  font-size: 0.75rem;
  font-weight: 500;
  white-space: nowrap;
  padding: 2px 6px;
  border-radius: 4px;
}

.sidebar-quick-stat:hover {
  color: var(--indigo-600);
  background: var(--slate-200);
}

/* 分隔线（高亮/批注 和 其他统计之间） */
.sidebar-quick-stat-divider {
  width: 1px;
  height: 14px;
  background-color: var(--slate-300);
  margin: 0 0.125rem;
}

.sidebar-settings-btn {
  padding: 0.375rem;
  color: var(--slate-500);
  background: transparent;
  border: none;
  border-radius: 0.5rem;
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.sidebar-settings-btn:hover {
  background: var(--slate-200);
  color: var(--slate-900);
}

/* ==================== 移动端遮罩 ==================== */

.sidebar-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.4);
  z-index: calc(var(--sidebar-z-index) - 10);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base);
  backdrop-filter: blur(2px);
}

.sidebar-overlay.show {
  opacity: 1;
  pointer-events: auto;
}

@media (min-width: 768px) {
  .sidebar-overlay {
    display: none;
  }
}

/* ==================== 主内容区 ==================== */

.app-main {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  position: relative;
  width: 100%;
  background-color: var(--color-bg-base);
}

/* ==================== 移动端顶部栏 ==================== */

.mobile-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1rem;
  background-color: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-light);
  position: sticky;
  top: 0;
  z-index: 10;
}

.mobile-header-title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.mobile-header-logo {
  width: 1.75rem;
  height: 1.75rem;
}

.mobile-menu-btn {
  padding: 0.25rem;
  color: var(--color-text-secondary);
  background: transparent;
  border: none;
  cursor: pointer;
}

@media (min-width: 768px) {
  .mobile-header {
    display: none;
  }
}

/* ==================== 分隔线 ==================== */

.sidebar-divider {
  height: 1px;
  background-color: var(--color-border-light);
  margin: 1rem 0.75rem;
  transition: margin var(--transition-fast);
}

/* ==================== 空状态提示 ==================== */

.sidebar-empty-state {
  padding: 0.75rem 1rem;
  text-align: center;
  color: var(--slate-400);
  font-size: 0.75rem;
}

.sidebar-empty-icon {
  display: none; /* 隐藏 emoji 图标 */
}

/* ==================== 工具提示 ==================== */

.sidebar-tooltip {
  position: absolute;
  left: 100%;
  margin-left: 0.5rem;
  padding: 0.375rem 0.75rem;
  background-color: var(--slate-800);
  color: var(--color-text-inverse);
  font-size: var(--font-size-xs);
  border-radius: var(--radius-sm);
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-fast);
  z-index: var(--z-tooltip);
  box-shadow: var(--shadow-md);
}

.nav-item:hover .sidebar-tooltip,
.sidebar-section-header:hover .sidebar-tooltip {
  opacity: 1;
}

/* 仅在收起状态显示工具提示 */
@media (min-width: 768px) {
  .app-sidebar:not(.collapsed) .sidebar-tooltip {
    display: none;
  }
}