/* ============================================
   云客 AI 营销平台 · 7 层全栈
   主调：蓝（系统）· 橙（ToC）· 紫（ToB）
   ============================================ */

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

:root {
  --blue: #165DFF;
  --blue-dark: #1249cc;
  --blue-soft: #E8F3FF;
  --orange: #FF7D00;
  --orange-soft: #FFF7E8;
  --orange-dark: #d96500;
  --green: #00B96B;
  --green-soft: #E8FFF3;
  --purple: #722ED1;
  --purple-soft: #F3E8FF;
  --purple-dark: #531dab;
  --cyan: #08979C;
  --cyan-soft: #E6FFFB;
  --red: #CF1322;
  --red-soft: #FFF1F0;
  --dark: #1d1d1f;
  --gray: #86868b;
  --gray-light: #c8c8cc;
  --light: #f5f5f7;
  --white: #fff;
  --line: #e5e5e5;
  --shadow-card: 0 12px 40px rgba(0,0,0,0.06);
  --shadow-hover: 0 16px 48px rgba(22, 93, 255, 0.12);
  --r-card: 20px;
  --r-md: 16px;
  --r-sm: 12px;
  --r-pill: 980px;
}

html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--dark);
  line-height: 1.6;
  background: var(--white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

.container { max-width: 1536px; margin: 0 auto; padding: 0 32px; }

/* ===== 导航 ===== */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  transition: box-shadow 0.3s, background 0.3s;
}
.nav-scrolled {
  box-shadow: 0 4px 20px rgba(0,0,0,0.04);
  background: rgba(255,255,255,0.92);
}
.nav-container {
  max-width: 1536px; margin: 0 auto; padding: 0 32px;
  display: flex; align-items: center; justify-content: space-between;
  height: 56px;
}
.logo { display: inline-flex; align-items: baseline; gap: 8px; }
.logo-mark { font-size: 20px; font-weight: 700; color: var(--dark); letter-spacing: -0.01em; }
.nav-links { display: flex; gap: 28px; list-style: none; align-items: center; }
.nav-links a { font-size: 14px; color: var(--dark); transition: color 0.2s; position: relative; }
.nav-links a:hover, .nav-links a.active { color: var(--blue); }
.nav-links a.active::after {
  content: ''; position: absolute; bottom: -6px; left: 0; right: 0;
  height: 2px; background: var(--blue); border-radius: 2px;
}
.nav-links .nav-cta {
  background: var(--blue); color: var(--white);
  padding: 8px 18px; border-radius: var(--r-pill);
  font-weight: 500;
}
.nav-links .nav-cta:hover { background: var(--blue-dark); color: var(--white); transform: scale(1.02); }
.nav-links .nav-cta.active::after { display: none; }
.menu-btn { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 4px; }
.menu-btn span { width: 20px; height: 2px; background: var(--dark); transition: 0.3s; }

/* ===== Page Header ===== */
.page-header {
  padding: 140px 24px 70px;
  background: linear-gradient(180deg, var(--light) 0%, var(--white) 100%);
  text-align: center;
  position: relative;
  overflow: hidden;
}
.page-header-bg {
  position: absolute; inset: 0;
  background-image:
    radial-gradient(circle at 18% 30%, rgba(22,93,255,0.08) 0%, transparent 38%),
    radial-gradient(circle at 82% 20%, rgba(255,125,0,0.08) 0%, transparent 40%),
    radial-gradient(circle at 50% 90%, rgba(114,46,209,0.05) 0%, transparent 50%);
  pointer-events: none;
}
.page-header-bg::before {
  content: '';
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(22,93,255,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(22,93,255,0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at center, black 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 0%, transparent 70%);
}
.page-header > .container { position: relative; z-index: 1; }
.page-header .tag {
  display: inline-block;
  padding: 7px 20px;
  background: linear-gradient(120deg, var(--blue) 0%, var(--purple) 100%);
  color: var(--white);
  border-radius: var(--r-pill);
  font-size: 13px; font-weight: 500;
  letter-spacing: 0.04em;
  margin-bottom: 24px;
}
.page-header h1 {
  font-size: clamp(56px, 10vw, 96px);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
  line-height: 1.1;
  background: linear-gradient(120deg, var(--blue) 0%, var(--purple) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.page-header p {
  font-size: clamp(17px, 2vw, 22px);
  color: var(--gray);
  margin-bottom: 32px;
}
.page-header-pills { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; }
.pill {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 18px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  font-size: 14px;
  color: var(--dark);
  box-shadow: 0 2px 8px rgba(0,0,0,0.03);
  transition: transform 0.2s, border-color 0.2s;
}
.pill i { color: var(--blue); }
.pill:hover { transform: translateY(-2px); border-color: var(--blue); }
.pill-toc { border-color: var(--orange); }
.pill-toc i { color: var(--orange); }
.pill-tob { border-color: var(--purple); }
.pill-tob i { color: var(--purple); }

/* ===== 产品概览 ===== */
.product-overview { padding: 70px 0 100px; background: var(--white); }
.overview-card {
  margin: 0 auto;
  text-align: center;
  padding: 48px 80px;
  background: var(--light);
  border-radius: var(--r-card);
  border: 1px solid var(--line);
}
.overview-desc { font-size: 17px; color: var(--dark); line-height: 1.85; margin-bottom: 32px; text-align: justify; max-width: 900px; margin-left: auto; margin-right: auto; }
.overview-desc strong { color: var(--blue); font-weight: 600; }
.overview-cta { display: flex; justify-content: center; flex-wrap: wrap; gap: 14px; margin-bottom: 32px; }
.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 32px;
  background: var(--blue); color: var(--white);
  border-radius: var(--r-pill);
  font-size: 16px; font-weight: 500;
  transition: transform 0.2s, background 0.2s, box-shadow 0.2s;
  box-shadow: 0 8px 24px rgba(22,93,255,0.28);
}
.btn-primary:hover {
  transform: scale(1.02);
  background: var(--blue-dark);
  box-shadow: 0 12px 32px rgba(22,93,255,0.36);
}
.btn-ghost {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 32px;
  background: var(--white); color: var(--dark);
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  font-size: 16px; font-weight: 500;
  transition: transform 0.2s, border-color 0.2s, color 0.2s;
}
.btn-ghost:hover { border-color: var(--blue); color: var(--blue); transform: translateY(-2px); }
.overview-trust { font-size: 14px; color: var(--gray); padding-top: 24px; border-top: 1px dashed var(--line); }
.overview-trust strong { color: var(--dark); font-weight: 500; margin: 0 8px; }

/* ===== Section ===== */
.section { padding: 100px 0; }
.section-tight { padding: 80px 0; }
.section-alt { background: var(--light); }
.section-head { text-align: center; max-width: 760px; margin: 0 auto 64px; }
.section-eyebrow {
  display: inline-block;
  font-size: 12px; font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--blue);
  padding: 6px 14px;
  background: var(--blue-soft);
  border-radius: var(--r-pill);
  margin-bottom: 20px;
}
.section-head h2 {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.25;
  color: var(--dark);
  margin-bottom: 16px;
}
.section-desc { font-size: 17px; color: var(--gray); line-height: 1.7; }
.section-desc strong { color: var(--dark); font-weight: 600; }
.section-conclusion {
  margin-top: 56px;
  padding: 24px 32px;
  background: var(--white);
  border-radius: var(--r-md);
  border: 1px solid var(--line);
  display: flex; align-items: center; justify-content: center;
  gap: 12px;
  font-size: 17px;
  color: var(--dark);
  text-align: center;
}
.section-alt .section-conclusion { background: var(--white); }
.section-conclusion i { color: var(--blue); font-size: 20px; }
.section-conclusion strong { color: var(--blue); font-weight: 600; }

/* ===== §2 范式跃迁 ===== */
.era-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.era-card {
  background: var(--white);
  padding: 36px 28px;
  border-radius: var(--r-card);
  border: 1px solid var(--line);
  transition: transform 0.3s, box-shadow 0.3s;
}
.era-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); }
.era-now {
  background: linear-gradient(180deg, #fff 0%, var(--blue-soft) 100%);
  border-color: var(--blue);
}
.era-tag {
  display: inline-block;
  font-size: 12px; font-weight: 500;
  letter-spacing: 0.1em;
  padding: 4px 12px;
  background: var(--light);
  color: var(--gray);
  border-radius: var(--r-pill);
  margin-bottom: 20px;
}
.era-tag-highlight { background: linear-gradient(120deg, var(--blue) 0%, var(--purple) 100%); color: var(--white); }
.era-card h3 { font-size: 22px; font-weight: 700; color: var(--dark); margin-bottom: 8px; }
.era-desc { font-size: 14px; color: var(--blue); margin-bottom: 20px; font-weight: 500; }
.era-past2 .era-desc { color: var(--orange); }
.era-card ul { margin-bottom: 24px; display: grid; gap: 8px; }
.era-card li { font-size: 14px; color: var(--dark); padding-left: 18px; position: relative; }
.era-card li::before {
  content: ''; position: absolute; left: 0; top: 9px;
  width: 6px; height: 6px;
  background: var(--blue); border-radius: 50%;
  opacity: 0.6;
}
.era-past .era-card li::before, .era-past2 .era-card li::before { background: var(--gray); }
.era-essence { padding-top: 20px; border-top: 1px dashed var(--line); font-size: 13px; color: var(--gray); }
.era-essence::before { content: '本质  '; color: var(--gray-light); font-weight: 500; }

/* ===== §3 7 层架构总览 ===== */
.arch-layers { display: flex; flex-direction: column; gap: 12px; }
.arch-layer {
  background: var(--white);
  border-radius: var(--r-card);
  padding: 24px 28px;
  border: 1px solid var(--line);
  display: grid;
  grid-template-columns: 60px 1fr;
  gap: 24px;
  align-items: center;
  transition: transform 0.3s, box-shadow 0.3s, border-left-color 0.3s;
  border-left: 4px solid var(--blue);
}
.arch-layer:hover {
  transform: translateX(4px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.05);
}
.arch-layer[data-layer="1"] { border-left-color: var(--cyan); }
.arch-layer[data-layer="2"] { border-left-color: var(--blue); }
.arch-layer[data-layer="3"] { border-left-color: var(--orange); }
.arch-layer[data-layer="4"] { border-left-color: var(--green); }
.arch-layer[data-layer="5"] { border-left-color: var(--purple); }
.arch-layer[data-layer="6"] { border-left-color: var(--red); }
.arch-layer-foundation { border-left-color: var(--dark) !important; background: linear-gradient(90deg, var(--light) 0%, var(--white) 60%); }
.arch-layer-num {
  font-size: 32px;
  font-weight: 700;
  color: var(--gray-light);
  letter-spacing: -0.02em;
  text-align: center;
  font-family: -apple-system, "SF Pro Display", "Inter", sans-serif;
}
.arch-layer-body { display: flex; flex-direction: column; gap: 14px; }
.arch-layer-head { display: flex; align-items: center; gap: 16px; }
.arch-layer-icon {
  width: 52px; height: 52px;
  border-radius: var(--r-md);
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
  flex-shrink: 0;
}
.arch-icon-data { background: var(--cyan-soft); color: var(--cyan); }
.arch-icon-content { background: var(--blue-soft); color: var(--blue); }
.arch-icon-target { background: var(--orange-soft); color: var(--orange); }
.arch-icon-convert { background: var(--green-soft); color: var(--green); }
.arch-icon-success { background: var(--purple-soft); color: var(--purple); }
.arch-icon-bi { background: var(--red-soft); color: var(--red); }
.arch-icon-foundation { background: var(--dark); color: #ffd56a; }
.arch-layer-head h3 { font-size: 20px; font-weight: 700; color: var(--dark); margin-bottom: 2px; }
.arch-layer-head p { font-size: 13px; color: var(--gray); }
.arch-layer-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.arch-tag {
  display: inline-block;
  font-size: 12px;
  padding: 5px 12px;
  background: var(--light);
  color: var(--dark);
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
}
.arch-tag-tob {
  background: var(--purple-soft);
  color: var(--purple);
  border-color: transparent;
  font-weight: 500;
}

/* ===== §4 ToC vs ToB 双线 ===== */
.dual-track { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.track-card {
  background: var(--white);
  border-radius: var(--r-card);
  padding: 36px 32px;
  border: 1px solid var(--line);
  border-top: 4px solid;
  transition: transform 0.3s, box-shadow 0.3s;
}
.track-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); }
.track-toc { border-top-color: var(--orange); background: linear-gradient(180deg, var(--white) 0%, var(--orange-soft) 100%); }
.track-tob { border-top-color: var(--purple); background: linear-gradient(180deg, var(--white) 0%, var(--purple-soft) 100%); }
.track-head { margin-bottom: 24px; padding-bottom: 20px; border-bottom: 1px dashed var(--line); }
.track-icon {
  width: 52px; height: 52px;
  border-radius: var(--r-md);
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
  margin-bottom: 14px;
}
.track-toc .track-icon { background: var(--orange); color: var(--white); }
.track-tob .track-icon { background: var(--purple); color: var(--white); }
.track-tag {
  display: inline-block;
  font-size: 11px;
  padding: 4px 10px;
  background: var(--orange);
  color: var(--white);
  border-radius: var(--r-pill);
  font-weight: 600;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}
.track-tag-tob { background: var(--purple); }
.track-head h3 { font-size: 24px; font-weight: 700; color: var(--dark); margin-bottom: 4px; }
.track-sub { font-size: 14px; color: var(--gray); }
.track-list { display: flex; flex-direction: column; gap: 14px; }
.track-list li { padding-left: 18px; border-left: 3px solid var(--light); transition: border-color 0.2s; }
.track-list li:hover { border-left-color: var(--orange); }
.track-tob .track-list li:hover { border-left-color: var(--purple); }
.track-list strong { display: block; font-size: 15px; font-weight: 700; color: var(--orange); margin-bottom: 2px; }
.track-tob .track-list strong { color: var(--purple); }
.track-list span { font-size: 13px; color: var(--gray); line-height: 1.6; }

/* ===== §4.5 真实用户故事 ===== */
.story-block {
  background: var(--white);
  border-radius: var(--r-card);
  padding: 0;
  border: 1px solid var(--line);
  overflow: hidden;
  margin-bottom: 32px;
}
.story-block:last-of-type { margin-bottom: 0; }
.story-toc { border-top: 4px solid var(--orange); }
.story-tob { border-top: 4px solid var(--purple); }

.story-hero {
  display: grid;
  grid-template-columns: 80px 1fr auto;
  gap: 20px;
  align-items: center;
  padding: 28px 32px;
  background: linear-gradient(120deg, var(--orange-soft) 0%, var(--white) 100%);
  border-bottom: 1px solid var(--line);
}
.story-tob .story-hero {
  background: linear-gradient(120deg, var(--purple-soft) 0%, var(--white) 100%);
}
.story-avatar {
  width: 64px; height: 64px;
  border-radius: 50%;
  background: var(--orange);
  color: var(--white);
  display: flex; align-items: center; justify-content: center;
  font-size: 30px;
  flex-shrink: 0;
  box-shadow: 0 4px 16px rgba(255,125,0,0.3);
}
.story-tob .story-avatar {
  background: var(--purple);
  box-shadow: 0 4px 16px rgba(114,46,209,0.3);
}
.story-hero-text { min-width: 0; }
.story-tag {
  display: inline-block;
  font-size: 11px;
  padding: 4px 10px;
  background: var(--orange);
  color: var(--white);
  border-radius: var(--r-pill);
  font-weight: 600;
  letter-spacing: 0.1em;
  margin-bottom: 6px;
}
.story-tag-tob { background: var(--purple); }
.story-hero-text h3 {
  font-size: 22px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 4px;
}
.story-bg {
  font-size: 13px;
  color: var(--gray);
  line-height: 1.65;
}
.story-bg strong { color: var(--dark); font-weight: 500; }

.story-result {
  text-align: right;
  padding: 16px 20px;
  background: var(--orange);
  color: var(--white);
  border-radius: var(--r-md);
  min-width: 200px;
}
.story-result-tob { background: var(--purple); }
.result-label {
  display: block;
  font-size: 11px;
  letter-spacing: 0.1em;
  opacity: 0.9;
  margin-bottom: 4px;
}
.story-result strong {
  display: block;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 4px;
}
.result-sub {
  display: block;
  font-size: 12px;
  opacity: 0.9;
}

.story-timeline {
  padding: 24px 32px;
  display: flex; flex-direction: column;
  gap: 0;
}
.story-step {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px dashed var(--line);
  position: relative;
}
.story-step:last-child { border-bottom: none; }
.story-step::before {
  content: '';
  position: absolute;
  left: 116px;
  top: 0; bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--orange) 0%, transparent 100%);
  opacity: 0.2;
}
.story-tob .story-step::before {
  background: linear-gradient(180deg, var(--purple) 0%, transparent 100%);
}
.story-step:first-child::before { top: 30px; }
.story-step:last-child::before { bottom: auto; height: 30px; }

.story-step-time {
  flex: 0 0 100px;
  font-size: 13px;
  font-weight: 700;
  color: var(--orange);
  letter-spacing: 0.03em;
  text-align: right;
  padding-top: 3px;
  position: relative;
  z-index: 1;
  background: var(--white);
}
.story-tob .story-step-time { color: var(--purple); }
.story-step-layer {
  flex: 0 0 150px;
  font-size: 12px;
  font-weight: 600;
  color: var(--gray);
  letter-spacing: 0.03em;
  padding: 4px 0 4px 32px;
  position: relative;
  z-index: 1;
  background: var(--white);
}
.story-step-layer::before {
  content: '';
  position: absolute;
  left: 6px;
  top: 7px;
  width: 12px;
  height: 12px;
  background: var(--orange);
  border-radius: 50%;
  border: 3px solid var(--white);
  box-shadow: 0 0 0 2px var(--orange);
  z-index: 2;
}
.story-tob .story-step-layer::before {
  background: var(--purple);
  box-shadow: 0 0 0 2px var(--purple);
}
.story-step-body {
  flex: 1;
  min-width: 0;
  position: relative;
}
.story-step-body strong {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 4px;
  line-height: 1.4;
}
.story-step-body p {
  font-size: 13px;
  color: var(--gray);
  line-height: 1.7;
}
.story-step-body p strong { display: inline; color: var(--orange-dark); font-weight: 600; font-size: 13px; }
.story-tob .story-step-body p strong { color: var(--purple-dark); }

.story-outcome {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  padding: 24px 32px;
  background: var(--orange-soft);
  border-top: 1px solid var(--line);
}
.story-outcome-tob { background: var(--purple-soft); }
.outcome-item {
  text-align: center;
  padding: 16px 12px;
  background: var(--white);
  border-radius: var(--r-md);
}
.outcome-item strong {
  display: block;
  font-size: 18px;
  font-weight: 700;
  color: var(--orange);
  letter-spacing: -0.01em;
  margin-bottom: 4px;
  font-family: -apple-system, "SF Pro Display", "Inter", sans-serif;
}
.story-outcome-tob .outcome-item strong { color: var(--purple); }
.outcome-item span {
  font-size: 11px;
  color: var(--gray);
}

@media (max-width: 1024px) {
  .story-hero { grid-template-columns: 64px 1fr; }
  .story-result { grid-column: 1 / -1; text-align: center; }
  .story-step { flex-wrap: wrap; }
  .story-step-time { flex: 0 0 80px; }
  .story-step-layer { flex: 0 0 120px; }
  .story-step-body { flex: 1 1 100%; padding-left: 0; padding-top: 8px; }
  .story-step::before { left: 94px; }
  .story-outcome { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .story-hero { grid-template-columns: 1fr; text-align: center; padding: 24px 20px; }
  .story-avatar { margin: 0 auto; }
  .story-step { flex-direction: column; gap: 6px; padding: 16px 0; }
  .story-step-time { flex: none; text-align: left; padding-left: 24px; }
  .story-step-layer { flex: none; text-align: left; padding-left: 24px; }
  .story-step-body { padding-left: 24px; padding-top: 0; }
  .story-step::before { display: none; }
  .story-step-layer::before { left: 9px; }
  .story-timeline { padding: 20px; }
  .story-outcome { padding: 20px; grid-template-columns: 1fr 1fr; }
}

/* ===== §5-§10 模块（双场景）通用 ===== */
.modules {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.module {
  background: var(--white);
  border-radius: var(--r-card);
  padding: 28px 26px;
  border: 1px solid var(--line);
  display: flex; flex-direction: column;
  transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}
.module:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); border-color: var(--blue); }
.module-highlight { background: linear-gradient(180deg, var(--white) 0%, var(--blue-soft) 100%); border-color: var(--blue); }
.module-highlight-tob { background: linear-gradient(180deg, var(--white) 0%, var(--purple-soft) 100%); border-color: var(--purple); }
.module-head { display: flex; align-items: center; gap: 14px; margin-bottom: 20px; padding-bottom: 16px; border-bottom: 1px dashed var(--line); }
.module-icon {
  width: 44px; height: 44px;
  border-radius: var(--r-md);
  background: var(--blue-soft);
  color: var(--blue);
  display: flex; align-items: center; justify-content: center;
  font-size: 18px;
  flex-shrink: 0;
}
.module-highlight-tob .module-icon { background: var(--purple-soft); color: var(--purple); }
.module-num {
  display: block;
  font-size: 11px;
  font-weight: 700;
  color: var(--gray-light);
  letter-spacing: 0.08em;
  margin-bottom: 2px;
  font-family: -apple-system, "SF Pro Display", "Inter", sans-serif;
}
.module-head h3 { font-size: 18px; font-weight: 700; color: var(--dark); }

.dual-scenario {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  flex: 1;
}
/* 有空场景的模块：自动切换为单列全宽 */
.dual-scenario:has(> .scenario-na) {
  grid-template-columns: 1fr;
}
.scenario-na { display: none; }
/* 全宽场景添加「专属」标识 */
.dual-scenario:has(> .scenario-na) > .scenario {
  padding: 20px 18px 20px 18px;
}
.dual-scenario:has(> .scenario-na) > .scenario-toc::after,
.dual-scenario:has(> .scenario-na) > .scenario-tob::after {
  content: '本模块仅适用于此场景';
  display: inline-block;
  margin-left: 8px;
  font-size: 10px;
  font-weight: 600;
  color: var(--gray);
  letter-spacing: 0.03em;
  padding: 2px 8px;
  background: rgba(255,255,255,0.7);
  border-radius: var(--r-pill);
  vertical-align: middle;
}
.scenario {
  padding: 16px 14px;
  border-radius: var(--r-md);
  border-top: 3px solid;
  background: var(--light);
}
.scenario-toc { border-top-color: var(--orange); background: var(--orange-soft); }
.scenario-tob { border-top-color: var(--purple); background: var(--purple-soft); }
.scenario-na { background: var(--light); border-top-color: var(--gray-light); opacity: 0.5; }
.scenario-tag {
  display: inline-block;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.1em;
  padding: 2px 8px;
  background: var(--orange);
  color: var(--white);
  border-radius: var(--r-pill);
  margin-bottom: 8px;
}
.scenario-tag-tob { background: var(--purple); }
.scenario p { font-size: 13px; color: var(--dark); line-height: 1.65; }
.scenario p strong { color: var(--orange-dark); font-weight: 600; }
.scenario-tob p strong { color: var(--purple-dark); }
.scenario-na p { color: var(--gray); text-align: center; font-size: 18px; padding-top: 14px; }

/* ===== §11 技术中台 ===== */
.foundation-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.foundation-card {
  background: var(--white);
  border-radius: var(--r-card);
  padding: 28px 24px;
  border: 1px solid var(--line);
  transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}
.foundation-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-hover); border-color: var(--blue); }
.foundation-card-highlight { background: linear-gradient(180deg, var(--white) 0%, var(--blue-soft) 100%); border-color: var(--blue); }
.foundation-icon {
  width: 48px; height: 48px;
  margin-bottom: 16px;
  border-radius: var(--r-md);
  background: var(--blue-soft);
  color: var(--blue);
  display: flex; align-items: center; justify-content: center;
  font-size: 20px;
}
.foundation-card strong { display: block; font-size: 16px; font-weight: 700; color: var(--dark); margin-bottom: 8px; }
.foundation-card p { font-size: 13px; color: var(--gray); line-height: 1.65; }
.foundation-card p strong { color: var(--blue); font-weight: 600; }

/* ===== §12 CTA ===== */
.cta-section { background: linear-gradient(180deg, var(--white) 0%, var(--light) 100%); }
.cta-final {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 56px;
  align-items: center;
  max-width: 1080px;
  margin: 0 auto;
}
.cta-final-text .section-eyebrow { margin-bottom: 16px; }
.cta-final-text h2 {
  font-size: clamp(32px, 4.5vw, 44px);
  font-weight: 700;
  color: var(--dark);
  letter-spacing: -0.01em;
  line-height: 1.25;
  margin-bottom: 20px;
}
.cta-final-desc { font-size: 16px; color: var(--gray); line-height: 1.8; margin-bottom: 28px; }
.cta-final-desc strong { color: var(--dark); font-weight: 600; }
.cta-final-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: 28px; }
.cta-trust {
  display: flex; flex-wrap: wrap; gap: 20px;
  font-size: 13px;
  color: var(--gray);
  padding-top: 24px;
  border-top: 1px dashed var(--line);
}
.cta-trust span { display: inline-flex; align-items: center; gap: 6px; }
.cta-trust i { color: var(--blue); }
.cta-final-card {
  background: var(--white);
  border-radius: var(--r-card);
  padding: 32px 28px;
  box-shadow: 0 20px 60px rgba(22,93,255,0.10);
  border: 1px solid var(--line);
  text-align: center;
}
.qr-placeholder {
  width: 220px; height: 220px;
  margin: 0 auto 20px;
  background: linear-gradient(135deg, var(--light) 0%, var(--blue-soft) 100%);
  border-radius: var(--r-md);
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: 8px;
  color: var(--blue);
}
.qr-placeholder i { font-size: 120px; opacity: 0.7; }
.qr-placeholder span { font-size: 13px; color: var(--dark); font-weight: 500; }
.cta-contact { display: flex; flex-direction: column; gap: 10px; text-align: left; }
.contact-row { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--gray); }
.contact-row i { color: var(--blue); width: 16px; }

/* ===== 页脚 ===== */
.footer { background: var(--dark); color: var(--white); padding: 60px 0 40px; text-align: center; }
.footer-brand { display: flex; flex-direction: column; align-items: center; gap: 8px; margin-bottom: 20px; }
.logo-mark-light { color: var(--white); font-size: 24px; font-weight: 700; }
.footer-tagline { font-size: 14px; color: rgba(255,255,255,0.6); margin-top: 8px; }
.footer-copy { font-size: 12px; color: rgba(255,255,255,0.4); opacity: 0.8; }

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .era-grid, .foundation-grid { grid-template-columns: repeat(2, 1fr); }
  .modules { grid-template-columns: 1fr; }
  .dual-track { grid-template-columns: 1fr; }
  .arch-layer { grid-template-columns: 50px 1fr; gap: 16px; padding: 20px 24px; }
  .cta-final { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 768px) {
  .menu-btn { display: flex; }
  .nav-links {
    position: absolute; top: 56px; left: 0; right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    padding: 20px 24px;
    gap: 16px;
    display: none;
    border-bottom: 1px solid var(--line);
  }
  .nav-links.active { display: flex; }
  .nav-links .nav-cta { text-align: center; }

  .section { padding: 60px 0; }
  .section-tight { padding: 48px 0; }
  .section-head { margin-bottom: 40px; }

  .era-grid, .foundation-grid { grid-template-columns: 1fr; }
  .modules { grid-template-columns: 1fr; }
  .dual-track { grid-template-columns: 1fr; }
  .dual-scenario { grid-template-columns: 1fr; }

  .page-header { padding: 100px 20px 50px; }
  .overview-card { padding: 32px 24px; }
  .arch-layer { grid-template-columns: 1fr; }
  .arch-layer-num { display: none; }
  .section-conclusion { padding: 18px 20px; font-size: 15px; flex-direction: column; gap: 8px; }
  .cta-final-text h2 { font-size: 28px; }
}


/* ===== Nav dropdown (产品中心二级菜单) ===== */
.nav-links li.has-dropdown { position: relative; }
.nav-links li.has-dropdown > a { padding-right: 18px; position: relative; }
.nav-links li.has-dropdown > a::after {
  content: '\f107';
  font-family: FontAwesome;
  position: absolute;
  right: 0; top: 50%;
  transform: translateY(-50%);
  font-size: 12px;
  opacity: 0.55;
  transition: transform 0.2s, opacity 0.2s;
}
.nav-links li.has-dropdown:hover > a::after {
  transform: translateY(-50%) rotate(180deg);
  opacity: 1;
}
.dropdown {
  position: absolute;
  top: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  background: #ffffff;
  min-width: 240px;
  list-style: none;
  padding: 8px 0;
  margin: 0;
  border-radius: 12px;
  box-shadow: 0 16px 40px rgba(0,0,0,0.10);
  border: 1px solid rgba(0,0,0,0.06);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
  z-index: 200;
}
.dropdown::before {
  content: '';
  position: absolute;
  top: -10px; left: 0; right: 0; height: 10px;
}
.dropdown li { padding: 0; }
.dropdown a {
  display: block;
  padding: 10px 20px;
  font-size: 14px;
  color: #1d1d1f;
  transition: background 0.15s, color 0.15s;
}
.dropdown a:hover {
  background: #f5f5f7;
  color: #165DFF;
}
.nav-links li.has-dropdown:hover .dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}
@media (max-width: 768px) {
  .dropdown {
    position: static;
    transform: none;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    border: none;
    background: rgba(0,0,0,0.03);
    margin: 8px 0 4px;
    border-radius: 8px;
    min-width: 0;
  }
  .dropdown::before { display: none; }
  .nav-links li.has-dropdown > a::after { display: none; }
}

/* ===== QR placeholder image (replaces fa-icon) ===== */
.qr-placeholder img {
  width: 180px;
  height: 180px;
  object-fit: contain;
  background: #fff;
  border-radius: 8px;
  padding: 8px;
  margin-bottom: 6px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.06);
}