/* ==================================================
   闪连VPN - 设备会话中心 核心样式表
   主题：象牙白 / 深蓝灰 / 墨绿 / 暖金棕
   ================================================== */

:root {
  /* 配色系统 (70% 象牙白/白, 20% 深蓝灰/墨绿/深文字, 10% 暖金棕) */
  --bg-primary: #FAF9F5;
  --bg-white: #FFFFFF;
  --bg-secondary: #F3F2EC;
  --bg-footer: #EFEEE8;
  
  --text-main: #1D272C;
  --text-body: #586269;
  --text-muted: #858E92;
  
  --blue-gray: #425F70;
  --blue-dark: #354E5C;
  --forest-green: #4F7469;
  --green-dark: #3F5F56;
  --gold-brown: #AE7952;
  
  --light-blue: #EEF2F3;
  --light-green: #EEF2EF;
  --light-warm: #F5EEE8;
  --border-color: #DFDDD5;
  
  /* 字体排版 */
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  --container-max: 1200px;
  --container-article: 820px;
  --transition-normal: 0.25s ease;
}

/* 全局重置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  background-color: var(--bg-primary);
  color: var(--text-main);
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font-stack);
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-body);
  background-color: var(--bg-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* 排版基础 */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-main);
  font-weight: 600;
  line-height: 1.35;
}

h1 {
  font-size: clamp(2rem, 4vw, 3rem); /* 32px - 48px */
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.6rem, 2.8vw, 2.2rem); /* 26px - 35px */
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.35rem; /* 21.6px */
}

p {
  margin-bottom: 1.25rem;
}

a {
  color: var(--blue-gray);
  text-decoration: none;
  transition: color var(--transition-normal);
}

a:hover {
  color: var(--gold-brown);
}

img, svg {
  vertical-align: middle;
}

ul, ol {
  padding-left: 1.5rem;
  margin-bottom: 1.25rem;
}

li {
  margin-bottom: 0.4rem;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.75rem;
}

th, td {
  padding: 0.9rem 1rem;
  border: 1px solid var(--border-color);
  text-align: left;
  font-size: 0.95rem;
}

th {
  background-color: var(--bg-secondary);
  color: var(--text-main);
  font-weight: 600;
}

/* 布局辅助 */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.site-main {
  flex: 1 0 auto;
}

.section-wrap {
  padding: 5rem 0;
  border-bottom: 1px solid var(--border-color);
}

.section-wrap.alt-bg {
  background-color: var(--bg-secondary);
}

.section-header {
  margin-bottom: 2.75rem;
}

.section-tag {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--forest-green);
  text-transform: none;
  letter-spacing: 0.05em;
  margin-bottom: 0.6rem;
}

.section-title {
  margin-bottom: 0.8rem;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-body);
  max-width: 800px;
  line-height: 1.8;
}

/* 按钮与CTA */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.6rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 4px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
  line-height: 1.4;
}

.btn-primary {
  background-color: var(--blue-gray);
  color: #FFFFFF;
  border-color: var(--blue-gray);
}

.btn-primary:hover {
  background-color: var(--blue-dark);
  color: #FFFFFF;
  border-color: var(--blue-dark);
}

.btn-primary:hover .btn-arrow {
  transform: translateX(3px);
}

.btn-secondary {
  background-color: #FFFFFF;
  color: var(--text-main);
  border-color: var(--border-color);
}

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

.btn-gold {
  background-color: var(--gold-brown);
  color: #FFFFFF;
  border-color: var(--gold-brown);
}

.btn-gold:hover {
  background-color: #96643F;
  color: #FFFFFF;
}

.btn-arrow {
  display: inline-block;
  transition: transform var(--transition-normal);
}

/* ==================================================
   Header
   ================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: 72px;
  background-color: var(--bg-white);
  border-bottom: 1px solid var(--border-color);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.header-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  line-height: 1.2;
}

.brand-subtitle {
  font-size: 0.72rem;
  color: var(--text-muted);
  line-height: 1.2;
  margin-top: 2px;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.nav-link {
  font-size: 0.92rem;
  color: var(--text-main);
  position: relative;
  padding: 0.4rem 0;
  font-weight: 500;
}

.nav-link:hover {
  color: var(--blue-gray);
}

.nav-link.active {
  color: var(--blue-gray);
  font-weight: 600;
}

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--blue-gray);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  padding: 0.45rem 0.65rem;
  border-radius: 4px;
  font-size: 0.9rem;
  color: var(--text-main);
  cursor: pointer;
  align-items: center;
  gap: 0.35rem;
}

/* 移动端菜单抽屉 */
.mobile-nav-drawer {
  display: none;
  position: fixed;
  top: 72px;
  left: 0;
  width: 100%;
  height: calc(100vh - 72px);
  background-color: var(--bg-white);
  border-top: 1px solid var(--border-color);
  overflow-y: auto;
  z-index: 99;
  padding: 1.5rem;
  flex-direction: column;
  gap: 1rem;
}

.mobile-nav-drawer.open {
  display: flex;
}

.mobile-nav-link {
  font-size: 1.05rem;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-main);
  display: block;
}

.mobile-nav-link.active {
  color: var(--blue-gray);
  font-weight: 600;
}

/* ==================================================
   Hero 设备会话板
   ================================================== */
.hero-section {
  padding: 4rem 0 4.5rem;
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
}

.hero-content {
  text-align: center;
  max-width: 860px;
  margin: 0 auto 3rem;
}

.hero-tag {
  display: inline-block;
  padding: 0.25rem 0.85rem;
  background-color: var(--light-blue);
  color: var(--blue-gray);
  border: 1px solid var(--border-color);
  border-radius: 30px;
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 1.25rem;
}

.hero-brand {
  font-size: 1.1rem;
  color: var(--gold-brown);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.hero-title {
  font-size: clamp(2rem, 3.8vw, 3rem);
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 1rem;
  line-height: 1.25;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--forest-green);
  font-weight: 500;
  margin-bottom: 1.25rem;
}

.hero-desc {
  font-size: 1.02rem;
  color: var(--text-body);
  line-height: 1.8;
  max-width: 760px;
  margin: 0 auto 1.75rem;
}

.hero-actions {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.85rem;
}

/* Hero 设备会话工作区 (不对称 2x2 + 中心微标) */
.hero-session-board {
  max-width: 1040px;
  margin: 0 auto;
  position: relative;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 2.25rem;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
}

.session-board-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-gap: 2rem;
  position: relative;
}

.session-device-card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.5rem 1.6rem;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.session-device-card:hover {
  border-color: var(--blue-gray);
  transform: translateY(-2px);
  background-color: #FFFFFF;
}

.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.75rem;
}

.device-name {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-main);
}

.device-badge {
  font-size: 0.75rem;
  padding: 0.15rem 0.55rem;
  border-radius: 4px;
  background-color: var(--light-blue);
  color: var(--blue-gray);
  border: 1px solid var(--border-color);
}

.device-desc {
  font-size: 0.92rem;
  color: var(--text-body);
  margin-bottom: 1.25rem;
  line-height: 1.6;
}

.device-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--blue-gray);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.device-link:hover {
  color: var(--gold-brown);
}

/* 会话板中心轻量标识 */
.session-center-indicator {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  padding: 0.45rem 0.95rem;
  border-radius: 20px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  pointer-events: none;
  z-index: 2;
  white-space: nowrap;
}

/* ==================================================
   01 / Windows 左右工作区
   ================================================== */
.windows-workspace {
  display: grid;
  grid-template-columns: 1.1fr 1.6fr 1.1fr;
  gap: 1.75rem;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 2.25rem;
}

.ws-col {
  display: flex;
  flex-direction: column;
}

.ws-col-title {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text-main);
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--light-blue);
  margin-bottom: 1.25rem;
}

.ws-intro-box {
  background-color: var(--light-green);
  border-left: 3px solid var(--forest-green);
  padding: 1.1rem;
  border-radius: 0 4px 4px 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--text-main);
  margin-bottom: 1.25rem;
}

.ws-task-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.ws-task-item {
  border: 1px solid var(--border-color);
  background-color: var(--bg-primary);
  padding: 0.9rem 1.1rem;
  border-radius: 4px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: border-color var(--transition-normal);
}

.ws-task-item:hover {
  border-color: var(--blue-gray);
  background-color: #FFFFFF;
}

.task-info {
  display: flex;
  flex-direction: column;
}

.task-name {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
}

.task-hint {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.task-action {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--blue-gray);
  white-space: nowrap;
}

/* ==================================================
   02 / macOS 连续任务列表
   ================================================== */
.macos-task-flow {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.macos-flow-item {
  display: grid;
  grid-template-columns: 80px 1fr auto;
  align-items: center;
  gap: 1.5rem;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.4rem 1.75rem;
  transition: border-color var(--transition-normal);
}

.macos-flow-item:hover {
  border-color: var(--forest-green);
}

.flow-step-num {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--forest-green);
  line-height: 1;
}

.flow-step-content h3 {
  font-size: 1.1rem;
  margin-bottom: 0.35rem;
}

.flow-step-content p {
  font-size: 0.92rem;
  margin-bottom: 0;
  color: var(--text-body);
}

/* ==================================================
   03 / Android 纵向移动任务
   ================================================== */
.android-mobile-tasks {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}

.android-task-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.4rem 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.android-task-card:hover {
  border-color: var(--gold-brown);
}

.android-card-header {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin-bottom: 0.65rem;
}

.android-badge {
  font-size: 0.78rem;
  padding: 0.15rem 0.45rem;
  background-color: var(--light-warm);
  color: var(--gold-brown);
  border-radius: 4px;
  font-weight: 600;
}

.android-task-card h3 {
  font-size: 1.05rem;
  color: var(--text-main);
}

.android-task-card p {
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--text-body);
  margin-bottom: 1rem;
}

/* ==================================================
   04 / iPhone 紧凑说明目录
   ================================================== */
.iphone-compact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.iphone-compact-box {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.5rem 1.75rem;
}

.iphone-compact-box h3 {
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.iphone-checklist {
  list-style: none;
  padding-left: 0;
  margin-bottom: 1rem;
}

.iphone-checklist li {
  font-size: 0.92rem;
  position: relative;
  padding-left: 1.4rem;
  margin-bottom: 0.65rem;
  color: var(--text-body);
  line-height: 1.6;
}

.iphone-checklist li::before {
  content: "•";
  position: absolute;
  left: 0.2rem;
  top: 0;
  color: var(--blue-gray);
  font-size: 1.2rem;
  line-height: 1.4;
}

/* ==================================================
   05 / AI工具 × 设备表
   ================================================== */
.responsive-table-wrap {
  overflow-x: auto;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
}

.responsive-table-wrap table {
  margin-bottom: 0;
  min-width: 720px;
}

.ai-tool-name {
  font-weight: 600;
  color: var(--text-main);
}

/* ==================================================
   06 / 流媒体 行式列表
   ================================================== */
.streaming-row-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.streaming-row {
  display: grid;
  grid-template-columns: 160px 1.2fr 1.2fr 1.2fr 120px;
  align-items: center;
  gap: 1.25rem;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.1rem 1.5rem;
  transition: border-color var(--transition-normal);
}

.streaming-row:hover {
  border-color: var(--blue-gray);
}

.streaming-platform {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text-main);
}

.streaming-col-label {
  display: none;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.streaming-col-val {
  font-size: 0.92rem;
  color: var(--text-body);
}

/* ==================================================
   07 / 节点与线路
   ================================================== */
.nodes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
  margin-bottom: 2.5rem;
}

.node-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.4rem;
}

.node-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.75rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-color);
}

.node-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
}

.node-badge {
  font-size: 0.75rem;
  padding: 0.1rem 0.5rem;
  background-color: var(--light-blue);
  color: var(--blue-gray);
  border-radius: 4px;
}

.node-device-usage {
  font-size: 0.9rem;
  line-height: 1.7;
}

.node-device-usage strong {
  color: var(--text-main);
}

/* ==================================================
   08 / 设备需求 × 套餐 (最重要商业区域)
   ================================================== */
.pricing-matrix-wrap {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  overflow-x: auto;
  box-shadow: 0 4px 16px rgba(0,0,0,0.03);
  margin-bottom: 2rem;
}

.pricing-table {
  width: 100%;
  min-width: 820px;
  border-collapse: collapse;
  margin-bottom: 0;
}

.pricing-table th, 
.pricing-table td {
  padding: 1.1rem 1rem;
  text-align: center;
  border: 1px solid var(--border-color);
}

.pricing-table th:first-child,
.pricing-table td:first-child {
  text-align: left;
  font-weight: 600;
  width: 22%;
  background-color: var(--bg-secondary);
}

/* 主力方案高亮列 */
.pricing-table th.highlight-col,
.pricing-table td.highlight-col {
  background-color: var(--light-green);
  border-left: 2px solid var(--forest-green);
  border-right: 2px solid var(--forest-green);
}

.pricing-table th.highlight-col {
  border-top: 3px solid var(--forest-green);
}

.plan-head-name {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.25rem;
}

.plan-badge-rec {
  display: inline-block;
  font-size: 0.72rem;
  background-color: var(--gold-brown);
  color: #FFFFFF;
  padding: 0.15rem 0.5rem;
  border-radius: 3px;
  margin-bottom: 0.4rem;
}

.plan-price {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--blue-dark);
}

.plan-data {
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* 矩阵符号说明 */
.symbol-bullet {
  color: var(--forest-green);
  font-size: 1.2rem;
  line-height: 1;
}

.symbol-check {
  color: var(--blue-gray);
  font-weight: 700;
}

.symbol-ref {
  color: var(--text-muted);
  font-size: 0.88rem;
}

.pricing-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  font-size: 0.88rem;
  color: var(--text-body);
  margin-bottom: 2rem;
  padding: 0.75rem 1rem;
  background-color: var(--bg-secondary);
  border-radius: 4px;
}

/* 长期方案独立区块 */
.longterm-plan-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.5rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.lt-left {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.lt-badge {
  font-size: 0.75rem;
  padding: 0.2rem 0.55rem;
  background-color: var(--light-warm);
  color: var(--gold-brown);
  border: 1px solid var(--gold-brown);
  border-radius: 4px;
  font-weight: 600;
}

.lt-name {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
}

.lt-specs {
  font-size: 0.95rem;
  color: var(--text-body);
}

.lt-price {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--blue-dark);
}

/* 快速选择参考 */
.quick-pick-guide {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.25rem 1.5rem;
}

.quick-pick-guide h4 {
  font-size: 0.95rem;
  color: var(--text-main);
  margin-bottom: 0.65rem;
}

.quick-pick-list {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.88rem;
}

.quick-pick-item {
  color: var(--text-body);
}

.quick-pick-item strong {
  color: var(--blue-gray);
}

/* 移动端套餐卡片容器 (默认桌面隐藏) */
.mobile-pricing-list {
  display: none;
  flex-direction: column;
  gap: 1.25rem;
}

.mobile-plan-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.25rem 1.4rem;
}

.mobile-plan-card.rec-card {
  border-color: var(--forest-green);
  border-top: 3px solid var(--forest-green);
  background-color: var(--light-green);
}

.mob-plan-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 0.75rem;
}

.mob-plan-params {
  list-style: none;
  padding-left: 0;
  margin-bottom: 1.1rem;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  padding: 0.75rem 0;
}

.mob-plan-params li {
  display: flex;
  justify-content: space-between;
  font-size: 0.88rem;
  margin-bottom: 0.35rem;
}

/* ==================================================
   09 / 评测区块 & 10 / 教程中心
   ================================================== */
.review-teaser-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 2.25rem;
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 2rem;
  align-items: center;
}

.review-teaser-content h3 {
  font-size: 1.35rem;
  margin-bottom: 0.85rem;
}

.review-teaser-content p {
  font-size: 0.95rem;
  margin-bottom: 1.25rem;
}

.review-check-list {
  list-style: none;
  padding-left: 0;
  margin-bottom: 1.5rem;
}

.review-check-list li {
  font-size: 0.9rem;
  position: relative;
  padding-left: 1.25rem;
  margin-bottom: 0.4rem;
}

.review-check-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--forest-green);
}

/* 教程中心 4 列分组 */
.tutorials-dir-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.tutorial-col {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
}

.tut-col-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  padding-bottom: 0.65rem;
  border-bottom: 2px solid var(--light-blue);
  margin-bottom: 1.1rem;
}

.tut-articles-list {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
  flex-grow: 1;
}

.tut-article-item {
  border-bottom: 1px dashed var(--border-color);
  padding-bottom: 0.85rem;
}

.tut-article-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.tut-article-item h4 {
  font-size: 0.95rem;
  margin-bottom: 0.35rem;
  line-height: 1.45;
}

.tut-article-item p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.55;
  margin-bottom: 0.45rem;
}

.tut-read-more {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--blue-gray);
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

/* ==================================================
   11 / 设备排障索引
   ================================================== */
.troubleshooting-index-wrap {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  overflow-x: auto;
}

.troubleshooting-index-wrap table {
  margin-bottom: 0;
}

.tb-device-name {
  font-weight: 700;
  color: var(--text-main);
  white-space: nowrap;
}

.troubleshooting-flow-steps {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  margin-bottom: 1.75rem;
  padding: 1rem 1.25rem;
  background-color: var(--bg-secondary);
  border-radius: 6px;
}

.tb-step-node {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-main);
  background-color: #FFFFFF;
  padding: 0.25rem 0.65rem;
  border-radius: 4px;
  border: 1px solid var(--border-color);
}

.tb-step-arrow {
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* ==================================================
   12 / 常见问题 (FAQ 设备问答目录)
   ================================================== */
.faq-dir-wrap {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.faq-item {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  overflow: hidden;
  transition: border-color var(--transition-normal);
}

.faq-item.active {
  border-color: var(--blue-gray);
}

.faq-trigger {
  width: 100%;
  background: none;
  border: none;
  padding: 1.15rem 1.5rem;
  text-align: left;
  display: grid;
  grid-template-columns: 110px 1fr 30px;
  align-items: center;
  gap: 1rem;
  cursor: pointer;
  font-family: inherit;
}

.faq-badge {
  font-size: 0.78rem;
  padding: 0.2rem 0.55rem;
  background-color: var(--light-blue);
  color: var(--blue-gray);
  border-radius: 4px;
  text-align: center;
  white-space: nowrap;
}

.faq-question-text {
  font-size: 1.02rem;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1.45;
}

.faq-toggle-icon {
  font-size: 1.25rem;
  font-weight: 400;
  color: var(--text-muted);
  text-align: right;
  line-height: 1;
}

.faq-item.active .faq-toggle-icon {
  color: var(--gold-brown);
}

.faq-answer {
  display: none;
  padding: 0 1.5rem 1.25rem 1.5rem;
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--text-body);
  border-top: 1px dashed var(--border-color);
  padding-top: 1rem;
}

.faq-item.active .faq-answer {
  display: block;
}

/* ==================================================
   Footer (浅象牙灰 商务编辑风)
   ================================================== */
.site-footer {
  background-color: var(--bg-footer);
  border-top: 1px solid var(--border-color);
  color: var(--text-body);
  padding: 3.5rem 0 2rem;
  margin-top: auto;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1fr 1.2fr;
  gap: 2rem;
  margin-bottom: 2.75rem;
}

.footer-col-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 1.1rem;
}

.footer-links {
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
}

.footer-links li {
  margin-bottom: 0.5rem;
}

.footer-links a {
  font-size: 0.88rem;
  color: var(--text-body);
}

.footer-links a:hover {
  color: var(--blue-gray);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.5rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--border-color);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-friend-links {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.footer-friend-links a {
  color: var(--text-body);
}

.footer-friend-links a:hover {
  color: var(--blue-gray);
}

/* ==================================================
   文章与分类单页排版
   ================================================== */
.page-container {
  width: 100%;
  max-width: var(--container-article);
  margin-left: auto;
  margin-right: auto;
  padding: 3.5rem 1.5rem 5rem;
}

.article-header {
  margin-bottom: 2.5rem;
}

.breadcrumbs {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

.breadcrumbs a {
  color: var(--text-muted);
}

.breadcrumbs a:hover {
  color: var(--blue-gray);
}

.article-category-tag {
  display: inline-block;
  font-size: 0.8rem;
  padding: 0.2rem 0.65rem;
  background-color: var(--light-blue);
  color: var(--blue-gray);
  border-radius: 4px;
  font-weight: 600;
  margin-bottom: 0.85rem;
}

.article-h1 {
  font-size: clamp(1.8rem, 3.2vw, 2.6rem);
  line-height: 1.35;
  margin-bottom: 1.25rem;
}

.article-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.25rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border-color);
}

/* 快速结论 (GEO 优先展示) */
.quick-conclusion-box {
  background-color: var(--light-green);
  border-left: 4px solid var(--forest-green);
  padding: 1.4rem 1.6rem;
  border-radius: 0 6px 6px 0;
  margin-bottom: 2.25rem;
}

.quick-conclusion-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--forest-green);
  margin-bottom: 0.45rem;
}

.quick-conclusion-text {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--text-main);
  margin-bottom: 0;
}

/* 目录 (TOC) */
.article-toc {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.4rem 1.6rem;
  margin-bottom: 2.5rem;
}

.toc-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.85rem;
}

.toc-list {
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
}

.toc-list li {
  margin-bottom: 0.45rem;
  font-size: 0.9rem;
}

.toc-list a {
  color: var(--blue-gray);
}

.toc-list a:hover {
  color: var(--gold-brown);
}

/* 正文样式 */
.article-body {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 2.5rem;
  font-size: 1.02rem;
  line-height: 1.88;
  color: var(--text-body);
}

.article-body h2 {
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-color);
}

.article-body h3 {
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
}

.article-body p {
  margin-bottom: 1.25rem;
}

.article-body ul, .article-body ol {
  margin-bottom: 1.5rem;
}

.article-callout {
  background-color: var(--light-blue);
  border-left: 4px solid var(--blue-gray);
  padding: 1.15rem 1.35rem;
  border-radius: 0 4px 4px 0;
  margin: 1.5rem 0;
  font-size: 0.95rem;
}

/* 文章底部互动与内链 */
.article-footer-nav {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

.related-articles-box {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.75rem;
  margin-bottom: 2rem;
}

.related-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 1rem;
}

.related-list {
  list-style: none;
  padding-left: 0;
  margin-bottom: 0;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.related-list li a {
  font-size: 0.95rem;
  color: var(--blue-gray);
  font-weight: 500;
}

.post-prev-next {
  display: flex;
  justify-content: space-between;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.post-pn-card {
  flex: 1;
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.1rem;
}

.pn-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.pn-title {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-main);
}

/* 分类页面文章列表 */
.category-article-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-top: 2rem;
}

.cat-article-card {
  background-color: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 1.75rem;
  transition: border-color var(--transition-normal);
}

.cat-article-card:hover {
  border-color: var(--blue-gray);
}

.cat-article-card h2 {
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
}

.cat-article-card p {
  font-size: 0.95rem;
  color: var(--text-body);
  margin-bottom: 1rem;
}

/* 404 与常规内容页 */
.error-page-content {
  text-align: center;
  padding: 4rem 1.5rem;
}

.error-code {
  font-size: 5rem;
  font-weight: 800;
  color: var(--blue-gray);
  line-height: 1;
  margin-bottom: 1rem;
}

.error-title {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
}

.error-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2rem;
}

/* ==================================================
   响应式断点 (1440, 1024, 768, 430, 390, 375)
   ================================================== */

@media (max-width: 1024px) {
  .windows-workspace {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  .tutorials-dir-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
  
  .streaming-row {
    grid-template-columns: 140px 1fr 1fr 110px;
  }
}

@media (max-width: 768px) {
  .site-header {
    height: 66px;
  }
  
  .header-nav {
    display: none;
  }
  
  .mobile-menu-toggle {
    display: flex;
  }
  
  .hero-section {
    padding: 2.75rem 0 3.5rem;
  }
  
  .session-board-grid {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }
  
  .session-center-indicator {
    display: none;
  }
  
  .macos-flow-item {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }
  
  .flow-step-num {
    font-size: 1.25rem;
  }
  
  .iphone-compact-grid {
    grid-template-columns: 1fr;
  }
  
  .streaming-row {
    grid-template-columns: 1fr;
    gap: 0.65rem;
  }
  
  .streaming-col-label {
    display: inline-block;
    font-weight: 600;
    margin-right: 0.4rem;
  }
  
  /* 隐藏桌面复杂表格，激活移动端套餐卡片 */
  .pricing-matrix-wrap {
    display: none;
  }
  
  .mobile-pricing-list {
    display: flex;
  }
  
  .longterm-plan-card {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .review-teaser-card {
    grid-template-columns: 1fr;
  }
  
  .tutorials-dir-grid {
    grid-template-columns: 1fr;
  }
  
  .faq-trigger {
    grid-template-columns: 1fr 30px;
    gap: 0.65rem;
  }
  
  .faq-badge {
    grid-column: span 2;
    justify-self: start;
  }
  
  .footer-top {
    grid-template-columns: 1fr;
  }
  
  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .article-body {
    padding: 1.5rem 1.25rem;
  }
  
  .post-prev-next {
    flex-direction: column;
  }
}

@media (max-width: 430px) {
  .hero-session-board {
    padding: 1.25rem;
  }
  
  .btn {
    width: 100%;
  }
  
  .hero-actions {
    flex-direction: column;
  }
  
  .node-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.35rem;
  }
}

/* ==================================================
   减少动画与无障碍 (prefers-reduced-motion)
   ================================================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  
  .session-device-card:hover,
  .btn-primary:hover .btn-arrow {
    transform: none !important;
  }
}