/* ==========================================================================
   赔钱机场 (peiqianjichangvpn.homes) - 官方视觉设计系统 2.0
   主题：垂直时间轴演进流（Vertical Timeline Rail）
   风格：老牌稳定 / 历史沉淀与技术透明
   配色：哑光纯黑(#000000) + 金黄色点缀(#EAB308) + 暗灰边框(#27272A)
   ========================================================================== */

:root {
  --bg-black: #000000;
  --bg-darker: #050505;
  --bg-dark: #09090B;
  --bg-card: #121215;
  --bg-card-hover: #18181C;
  --bg-glass: rgba(18, 18, 21, 0.75);

  --accent-gold: #EAB308;
  --accent-gold-hover: #CA8A04;
  --accent-gold-light: rgba(234, 179, 8, 0.12);
  --accent-gold-glow: rgba(234, 179, 8, 0.45);
  --accent-gold-intense: #FACC15;

  --border-dark: #27272A;
  --border-card: #202024;
  --border-gold: rgba(234, 179, 8, 0.35);

  --text-primary: #F4F4F5;
  --text-secondary: #D4D4D8;
  --text-muted: #A1A1AA;
  --text-sub: #71717A;

  --shadow-dark: 0 10px 30px -10px rgba(0, 0, 0, 0.8);
  --shadow-gold: 0 0 25px rgba(234, 179, 8, 0.25);
  --shadow-gold-lg: 0 0 40px rgba(234, 179, 8, 0.4);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-full: 9999px;

  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text-primary);
  background-color: var(--bg-black);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
  position: relative;
  min-height: 100vh;
  background-color: var(--bg-black);
}

/* 顶部黑金流光公告栏 */
.announcement-bar {
  background: linear-gradient(90deg, #000000 0%, #151206 50%, #000000 100%);
  color: #F4F4F5;
  padding: 10px 16px;
  font-size: 13.5px;
  position: relative;
  z-index: 100;
  border-bottom: 1px solid var(--border-dark);
}

.announcement-inner {
  max-width: 1240px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.announcement-tag {
  background: var(--accent-gold);
  color: #000000;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-weight: 800;
  font-size: 11px;
  margin-right: 8px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  box-shadow: 0 0 12px rgba(234, 179, 8, 0.6);
}

.announcement-text {
  display: flex;
  align-items: center;
  font-weight: 500;
  letter-spacing: 0.3px;
}

.announcement-link {
  color: var(--accent-gold);
  text-decoration: none;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: var(--transition-fast);
}

.announcement-link:hover {
  color: #FDE047;
  transform: translateX(3px);
  text-shadow: 0 0 10px rgba(234, 179, 8, 0.8);
}

/* 动态背景画布 */
#bg-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  pointer-events: none;
  opacity: 0.7;
}

/* 顶部导航栏 (黑金磨砂玻璃) */
.navbar {
  position: sticky;
  top: 0;
  background: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-dark);
  z-index: 99;
  transition: var(--transition-normal);
}

.navbar.scrolled {
  background: rgba(5, 5, 5, 0.96);
  border-bottom-color: rgba(234, 179, 8, 0.2);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.9);
}

.nav-container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo-area {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, #1C1917 0%, #292524 100%);
  border: 1.5px solid var(--accent-gold);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-gold);
  box-shadow: 0 0 15px rgba(234, 179, 8, 0.35);
  font-size: 18px;
}

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

.logo-title {
  font-size: 20px;
  font-weight: 900;
  letter-spacing: -0.5px;
  color: #FFFFFF;
  line-height: 1.2;
}

.logo-title span {
  color: var(--accent-gold);
}

.logo-desc {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 500;
  letter-spacing: 0.5px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 14.5px;
  position: relative;
  transition: color var(--transition-fast);
  padding: 6px 0;
}

.nav-links a:hover, .nav-links a.active {
  color: var(--accent-gold);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-gold);
  border-radius: 2px;
  transition: width var(--transition-fast);
  box-shadow: 0 0 8px var(--accent-gold);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* 按钮规范 */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--accent-gold);
  color: #000000;
  font-weight: 800;
  padding: 10px 22px;
  border-radius: var(--radius-full);
  text-decoration: none;
  border: none;
  cursor: pointer;
  box-shadow: 0 0 20px rgba(234, 179, 8, 0.4);
  transition: all var(--transition-fast);
}

.btn-primary:hover {
  background: var(--accent-gold-intense);
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(234, 179, 8, 0.7);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: #141417;
  color: var(--text-primary);
  font-weight: 700;
  padding: 10px 20px;
  border-radius: var(--radius-full);
  text-decoration: none;
  border: 1.5px solid var(--border-dark);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-secondary:hover {
  border-color: var(--accent-gold);
  color: var(--accent-gold);
  background: #1C1917;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 22px;
  color: var(--text-primary);
  cursor: pointer;
}

/* 核心布局 */
.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 80px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 780px;
  margin: 0 auto 50px auto;
}

.section-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--accent-gold-light);
  color: var(--accent-gold);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 800;
  margin-bottom: 14px;
  border: 1px solid var(--border-gold);
  box-shadow: 0 0 15px rgba(234, 179, 8, 0.2);
}

.section-title {
  font-size: 34px;
  font-weight: 900;
  color: #FFFFFF;
  line-height: 1.25;
  margin-bottom: 14px;
  letter-spacing: -0.5px;
}

.section-title span {
  color: var(--accent-gold);
}

.section-desc {
  font-size: 16px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ==========================================================================
   核心排版：垂直时间轴演进流（Vertical Timeline Rail）
   老牌稳定 / 历史沉淀与技术透明
   ========================================================================== */
.timeline-hero-section {
  padding: 60px 0 100px 0;
  position: relative;
  background: radial-gradient(circle at 50% 10%, rgba(234, 179, 8, 0.08) 0%, transparent 60%);
}

.timeline-intro {
  text-align: center;
  max-width: 820px;
  margin: 0 auto 60px auto;
}

.timeline-main-title {
  font-size: 38px;
  font-weight: 900;
  color: #FFFFFF;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.timeline-main-title span {
  color: var(--accent-gold);
  text-shadow: 0 0 20px rgba(234, 179, 8, 0.4);
}

.timeline-sub-title {
  font-size: 16px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* 时间轴主体轨道 */
.timeline-rail-wrapper {
  position: relative;
  max-width: 1040px;
  margin: 0 auto;
  padding: 40px 0;
}

/* 页面正中央发光垂直轴线 */
.timeline-rail-line {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 3px;
  background: var(--border-dark);
  transform: translateX(-50%);
  z-index: 1;
}

/* 滚动时点亮的发光覆盖层 */
.timeline-rail-glow {
  position: absolute;
  top: 0;
  left: 50%;
  width: 3px;
  height: 0%;
  background: linear-gradient(180deg, var(--accent-gold) 0%, #F59E0B 100%);
  transform: translateX(-50%);
  z-index: 2;
  box-shadow: 0 0 15px var(--accent-gold), 0 0 30px var(--accent-gold);
  transition: height 0.2s ease-out;
}

/* 单个时间轴节点 */
.timeline-node-item {
  position: relative;
  z-index: 3;
  margin-bottom: 80px;
  display: flex;
  align-items: center;
  width: 100%;
}

.timeline-node-item:last-child {
  margin-bottom: 0;
}

/* 奇数节点在左，偶数节点在右 */
.timeline-node-item.node-left {
  justify-content: flex-start;
}

.timeline-node-item.node-right {
  justify-content: flex-end;
}

.node-content-card {
  width: 44%;
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-dark);
  position: relative;
  transition: all var(--transition-normal);
  opacity: 0.35;
  transform: translateY(20px);
}

.timeline-node-item.active .node-content-card {
  opacity: 1;
  transform: translateY(0);
  border-color: var(--border-gold);
  box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.9), 0 0 25px rgba(234, 179, 8, 0.2);
}

/* 中央时间轴圆点节点 */
.node-rail-marker {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: #09090B;
  border: 2px solid var(--border-dark);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 16px;
  z-index: 4;
  transition: all var(--transition-normal);
}

.timeline-node-item.active .node-rail-marker {
  background: #000000;
  border-color: var(--accent-gold);
  color: var(--accent-gold);
  box-shadow: 0 0 0 6px rgba(234, 179, 8, 0.2), 0 0 25px var(--accent-gold);
}

.node-badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--accent-gold-light);
  color: var(--accent-gold);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 800;
  margin-bottom: 12px;
  border: 1px solid var(--border-gold);
}

.node-title {
  font-size: 22px;
  font-weight: 900;
  color: #FFFFFF;
  margin-bottom: 12px;
  line-height: 1.35;
}

.node-desc {
  font-size: 14.5px;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 20px;
}

/* 节点1：历史回放指标卡 */
.sla-metrics-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.sla-item {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
}

.sla-item-num {
  font-size: 20px;
  font-weight: 900;
  color: var(--accent-gold);
}

.sla-item-lbl {
  font-size: 11px;
  color: var(--text-sub);
}

/* 节点2：骨干网架构拓扑 */
.network-flow-diag {
  background: #09090C;
  border: 1px dashed var(--border-dark);
  border-radius: var(--radius-md);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.flow-step {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12.5px;
  color: var(--text-secondary);
}

.flow-step span.step-pill {
  background: #27272A;
  color: #F4F4F5;
  padding: 3px 8px;
  border-radius: 4px;
  font-weight: 700;
  font-size: 11px;
}

.flow-step span.step-arrow {
  color: var(--accent-gold);
  font-weight: 900;
}

/* 节点3：晚高峰实测散点图面板 */
.speed-test-scatter {
  background: #09090C;
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-md);
  padding: 16px;
}

.scatter-head {
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-sub);
  margin-bottom: 12px;
  border-bottom: 1px solid var(--border-dark);
  padding-bottom: 8px;
}

.scatter-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  padding: 6px 0;
  border-bottom: 1px solid rgba(39, 39, 42, 0.4);
}

.scatter-row:last-child {
  border-bottom: none;
}

.scatter-node-name {
  font-weight: 700;
  color: #FFFFFF;
}

.scatter-speed {
  color: var(--accent-gold);
  font-weight: 800;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.scatter-loss {
  color: #10B981;
  font-size: 11px;
  font-weight: 700;
}

/* 节点4：终端三阶梯直连落点 */
.node-pricing-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.node-price-mini {
  background: #09090C;
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all var(--transition-fast);
}

.node-price-mini:hover {
  border-color: var(--accent-gold);
  transform: translateX(4px);
}

.mini-plan-info h5 {
  font-size: 15px;
  font-weight: 800;
  color: #FFFFFF;
}

.mini-plan-info p {
  font-size: 12px;
  color: var(--text-muted);
}

.mini-plan-cost {
  font-size: 20px;
  font-weight: 900;
  color: var(--accent-gold);
}

.mini-plan-cost span {
  font-size: 12px;
  color: var(--text-sub);
}

/* ==========================================================================
   板块3：节点延迟和状态大屏 (黑金极简仪表盘)
   ========================================================================== */
.nodes-section {
  background: var(--bg-darker);
  border-top: 1px solid var(--border-dark);
  border-bottom: 1px solid var(--border-dark);
}

.nodes-status-header {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 20px 28px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  border: 1px solid var(--border-dark);
  margin-bottom: 24px;
}

.nodes-stat-item {
  display: flex;
  align-items: center;
  gap: 14px;
}

.stat-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--accent-gold-light);
  color: var(--accent-gold);
  border: 1px solid var(--border-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
}

.stat-content h4 {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 600;
}

.stat-content p {
  font-size: 19px;
  font-weight: 900;
  color: #FFFFFF;
}

.nodes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 18px;
}

.node-card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-dark);
  padding: 22px;
  box-shadow: var(--shadow-dark);
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.node-card:hover {
  border-color: var(--accent-gold);
  transform: translateY(-3px);
  box-shadow: 0 0 20px rgba(234, 179, 8, 0.15);
}

.node-card-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
}

.node-flag-title {
  display: flex;
  align-items: center;
  gap: 10px;
}

.node-flag {
  font-size: 22px;
}

.node-name {
  font-size: 15px;
  font-weight: 800;
  color: #FFFFFF;
}

.node-type {
  font-size: 11px;
  color: var(--accent-gold);
  background: var(--accent-gold-light);
  border: 1px solid var(--border-gold);
  padding: 2px 7px;
  border-radius: 4px;
  font-weight: 800;
}

.node-latency-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12.5px;
  font-weight: 800;
  color: var(--accent-gold);
}

.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-gold);
  box-shadow: 0 0 0 rgba(234, 179, 8, 0.8);
  animation: pulseGold 2s infinite;
}

@keyframes pulseGold {
  0% {
    box-shadow: 0 0 0 0 rgba(234, 179, 8, 0.8);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(234, 179, 8, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(234, 179, 8, 0);
  }
}

.node-metrics {
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 10px;
}

.node-progress-bar {
  height: 4px;
  background: #27272A;
  border-radius: 10px;
  overflow: hidden;
  margin-bottom: 14px;
}

.node-progress-val {
  height: 100%;
  background: linear-gradient(90deg, #CA8A04 0%, var(--accent-gold) 100%);
  border-radius: 10px;
}

.node-tags {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.node-tag {
  font-size: 11px;
  color: var(--text-secondary);
  background: #1C1917;
  border: 1px solid #292524;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
}

/* ==========================================================================
   板块4：核心优势板块
   ========================================================================== */
.features-section {
  background: var(--bg-black);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.feature-box {
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-md);
  padding: 30px 24px;
  transition: all var(--transition-fast);
}

.feature-box:hover {
  border-color: var(--accent-gold);
  transform: translateY(-4px);
  box-shadow: 0 0 25px rgba(234, 179, 8, 0.15);
}

.feature-icon-wrapper {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  background: var(--accent-gold-light);
  color: var(--accent-gold);
  border: 1px solid var(--border-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  margin-bottom: 20px;
  transition: all var(--transition-fast);
}

.feature-box:hover .feature-icon-wrapper {
  background: var(--accent-gold);
  color: #000000;
}

.feature-title {
  font-size: 18px;
  font-weight: 800;
  color: #FFFFFF;
  margin-bottom: 10px;
}

.feature-text {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.65;
}

/* ==========================================================================
   板块4-续：套餐价格板块 (15月付、22月付、120年付)
   ========================================================================== */
.pricing-section {
  background: var(--bg-darker);
  border-top: 1px solid var(--border-dark);
}

.pricing-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 28px;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-lg);
  padding: 38px 30px;
  box-shadow: var(--shadow-dark);
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  position: relative;
}

.pricing-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent-gold);
  box-shadow: 0 0 35px rgba(234, 179, 8, 0.2);
}

.pricing-card.featured {
  border: 2px solid var(--accent-gold);
  box-shadow: 0 0 40px rgba(234, 179, 8, 0.25);
  transform: scale(1.03);
}

.pricing-card.featured:hover {
  transform: scale(1.05) translateY(-6px);
}

.featured-ribbon {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(90deg, #FACC15 0%, #EAB308 100%);
  color: #000000;
  font-size: 12px;
  font-weight: 900;
  padding: 4px 18px;
  border-radius: var(--radius-full);
  letter-spacing: 0.5px;
  box-shadow: 0 0 15px rgba(234, 179, 8, 0.6);
}

.plan-header {
  border-bottom: 1px solid var(--border-dark);
  padding-bottom: 24px;
  margin-bottom: 24px;
  text-align: center;
}

.plan-name {
  font-size: 22px;
  font-weight: 900;
  color: #FFFFFF;
  margin-bottom: 8px;
}

.plan-desc {
  font-size: 13.5px;
  color: var(--text-muted);
  min-height: 42px;
}

.plan-price-wrap {
  margin: 16px 0;
  display: flex;
  align-items: baseline;
  justify-content: center;
}

.plan-currency {
  font-size: 24px;
  font-weight: 800;
  color: var(--accent-gold);
}

.plan-price {
  font-size: 50px;
  font-weight: 900;
  color: #FFFFFF;
  line-height: 1;
}

.plan-period {
  font-size: 14px;
  color: var(--text-sub);
  margin-left: 6px;
  font-weight: 600;
}

.plan-features-list {
  list-style: none;
  margin-bottom: 30px;
  flex-grow: 1;
}

.plan-features-list li {
  font-size: 14px;
  color: var(--text-secondary);
  padding: 8px 0;
  display: flex;
  align-items: center;
  gap: 10px;
}

.plan-features-list li i {
  color: var(--accent-gold);
  font-size: 16px;
  flex-shrink: 0;
}

.plan-features-list li.disabled {
  color: #52525B;
}

.plan-features-list li.disabled i {
  color: #3F3F46;
}

.btn-plan {
  width: 100%;
  padding: 13px;
  font-size: 16px;
}

/* ==========================================================================
   板块5：常见问题 FAQ 手风琴
   ========================================================================== */
.faq-section {
  background: var(--bg-black);
}

.faq-accordion {
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-md);
  margin-bottom: 14px;
  overflow: hidden;
  transition: all var(--transition-fast);
}

.faq-item:hover {
  border-color: #3F3F46;
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: none;
  border: none;
  text-align: left;
  font-size: 16px;
  font-weight: 800;
  color: #FFFFFF;
  cursor: pointer;
  transition: color var(--transition-fast);
}

.faq-question:hover {
  color: var(--accent-gold);
}

.faq-chevron {
  font-size: 16px;
  color: var(--text-sub);
  transition: transform var(--transition-fast);
}

.faq-item.active .faq-chevron {
  transform: rotate(180deg);
  color: var(--accent-gold);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease-out;
  background: #09090C;
  border-top: 1px solid transparent;
}

.faq-item.active .faq-answer {
  max-height: 500px;
  border-top-color: var(--border-dark);
}

.faq-answer-inner {
  padding: 20px 24px;
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.75;
}

/* ==========================================================================
   板块6：知识库与教程板块
   ========================================================================== */
.articles-section {
  background: var(--bg-darker);
  border-top: 1px solid var(--border-dark);
}

.articles-tabs {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 8px 18px;
  border-radius: var(--radius-full);
  border: 1.5px solid var(--border-dark);
  background: var(--bg-card);
  color: var(--text-muted);
  font-weight: 700;
  font-size: 14px;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.tab-btn.active, .tab-btn:hover {
  background: var(--accent-gold);
  color: #000000;
  border-color: var(--accent-gold);
  box-shadow: 0 0 15px rgba(234, 179, 8, 0.4);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 28px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-md);
  padding: 26px;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-fast);
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow-dark);
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-gold);
  box-shadow: 0 0 25px rgba(234, 179, 8, 0.15);
}

.article-tag {
  align-self: flex-start;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 800;
  margin-bottom: 14px;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.tag-stream {
  background: rgba(239, 68, 68, 0.15);
  color: #F87171;
  border-color: rgba(239, 68, 68, 0.3);
}

.tag-client {
  background: rgba(59, 130, 246, 0.15);
  color: #60A5FA;
  border-color: rgba(59, 130, 246, 0.3);
}

.tag-ai {
  background: rgba(16, 185, 129, 0.15);
  color: #34D399;
  border-color: rgba(16, 185, 129, 0.3);
}

.tag-game {
  background: rgba(234, 179, 8, 0.15);
  color: #FACC15;
  border-color: rgba(234, 179, 8, 0.3);
}

.tag-trade {
  background: rgba(168, 85, 247, 0.15);
  color: #C084FC;
  border-color: rgba(168, 85, 247, 0.3);
}

.article-title {
  font-size: 17.5px;
  font-weight: 800;
  color: #FFFFFF;
  margin-bottom: 10px;
  line-height: 1.45;
  transition: color var(--transition-fast);
}

.article-card:hover .article-title {
  color: var(--accent-gold);
}

.article-excerpt {
  font-size: 13.5px;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 18px;
  flex-grow: 1;
}

.article-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--text-sub);
  border-top: 1px solid #1C1917;
  padding-top: 14px;
}

.article-readmore {
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--accent-gold);
  font-weight: 800;
}

/* ==========================================================================
   板块7：真实用户评价
   ========================================================================== */
.reviews-section {
  background: var(--bg-black);
}

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-md);
  padding: 26px;
  box-shadow: var(--shadow-dark);
  display: flex;
  flex-direction: column;
}

.review-stars {
  color: var(--accent-gold);
  font-size: 14px;
  margin-bottom: 12px;
  letter-spacing: 2px;
}

.review-content {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
  flex-grow: 1;
  font-style: italic;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid #1F1F23;
  padding-top: 14px;
}

.author-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: #27272A;
  color: var(--accent-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 15px;
  border: 1px solid var(--border-gold);
}

.author-info h5 {
  font-size: 14px;
  font-weight: 800;
  color: #FFFFFF;
}

.author-info p {
  font-size: 12px;
  color: var(--text-sub);
}

/* ==========================================================================
   CTA 底部通栏 (黑金光芒)
   ========================================================================== */
.cta-banner-section {
  background: linear-gradient(135deg, #09090B 0%, #17150C 50%, #09090B 100%);
  color: #FFFFFF;
  padding: 70px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
  border-top: 1px solid var(--border-gold);
}

.cta-banner-section::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(234, 179, 8, 0.12) 0%, transparent 60%);
  pointer-events: none;
}

.cta-content {
  position: relative;
  z-index: 2;
  max-width: 720px;
  margin: 0 auto;
}

.cta-content h2 {
  font-size: 34px;
  font-weight: 900;
  margin-bottom: 14px;
  color: #FFFFFF;
}

.cta-content h2 span {
  color: var(--accent-gold);
}

.cta-content p {
  font-size: 16px;
  color: var(--text-muted);
  margin-bottom: 28px;
}

/* ==========================================================================
   页脚 Footer
   ========================================================================== */
.footer {
  background: #000000;
  color: var(--text-muted);
  padding: 60px 0 24px 0;
  border-top: 1px solid var(--border-dark);
  font-size: 14px;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 50px;
}

.footer-brand h3 {
  font-size: 20px;
  font-weight: 900;
  color: #FFFFFF;
  margin-bottom: 12px;
}

.footer-brand h3 span {
  color: var(--accent-gold);
}

.footer-brand p {
  line-height: 1.7;
  max-width: 320px;
}

.footer-col h4 {
  font-size: 15px;
  font-weight: 800;
  color: #FFFFFF;
  margin-bottom: 16px;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--accent-gold);
}

.footer-bottom {
  border-top: 1px solid #18181B;
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
}

/* 独立文章详情页专用黑金样式 */
.article-page-body {
  background: var(--bg-black);
  color: var(--text-primary);
}

.article-header {
  background: linear-gradient(180deg, rgba(234, 179, 8, 0.04) 0%, transparent 100%);
  padding: 50px 0 30px 0;
  border-bottom: 1px solid var(--border-dark);
}

.article-breadcrumbs {
  font-size: 13px;
  color: var(--text-sub);
  margin-bottom: 16px;
}

.article-breadcrumbs a {
  color: var(--accent-gold);
  text-decoration: none;
  font-weight: 600;
}

.article-detail-title {
  font-size: 32px;
  font-weight: 900;
  color: #FFFFFF;
  line-height: 1.3;
  margin-bottom: 16px;
}

.article-detail-meta {
  display: flex;
  gap: 20px;
  font-size: 13px;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.article-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 40px;
  padding: 50px 0;
}

.article-content {
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-secondary);
}

.article-content h2 {
  font-size: 24px;
  font-weight: 800;
  color: #FFFFFF;
  margin: 36px 0 16px 0;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-dark);
}

.article-content h3 {
  font-size: 19px;
  font-weight: 700;
  color: var(--accent-gold);
  margin: 26px 0 12px 0;
}

.article-content p {
  margin-bottom: 18px;
}

.article-content ul, .article-content ol {
  margin-bottom: 20px;
  padding-left: 24px;
}

.article-content li {
  margin-bottom: 8px;
}

.article-content blockquote {
  background: #121215;
  border-left: 4px solid var(--accent-gold);
  padding: 16px 20px;
  margin: 24px 0;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-secondary);
  border-top: 1px solid var(--border-dark);
  border-bottom: 1px solid var(--border-dark);
  border-right: 1px solid var(--border-dark);
}

.article-content pre {
  background: #09090C;
  color: #F8FAFC;
  padding: 16px 20px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-dark);
  overflow-x: auto;
  font-family: Consolas, Monaco, monospace;
  font-size: 14px;
  margin: 20px 0;
}

.article-sidebar {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.sidebar-card {
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-dark);
}

.sidebar-card h4 {
  font-size: 16px;
  font-weight: 800;
  color: #FFFFFF;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-dark);
}

.sidebar-links {
  list-style: none;
}

.sidebar-links li {
  margin-bottom: 12px;
}

.sidebar-links a {
  text-decoration: none;
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.5;
  display: block;
  transition: color var(--transition-fast);
}

.sidebar-links a:hover {
  color: var(--accent-gold);
}

/* 响应式适配 */
@media (max-width: 992px) {
  .timeline-rail-line, .timeline-rail-glow {
    left: 24px;
  }
  .timeline-node-item {
    justify-content: flex-start !important;
    padding-left: 54px;
  }
  .node-content-card {
    width: 100%;
  }
  .node-rail-marker {
    left: 24px;
  }
  .article-layout {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: #09090B;
    flex-direction: column;
    padding: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.9);
    border-bottom: 1px solid var(--border-dark);
  }
  .nav-links.mobile-active {
    display: flex;
  }
  .mobile-menu-btn {
    display: block;
  }
  .timeline-main-title {
    font-size: 26px;
  }
  .section-title {
    font-size: 26px;
  }
  .footer-top {
    grid-template-columns: 1fr;
  }
}