/* ============================================
   杭韵绘影 · 高端品牌站样式系统 v2.0
   主色调：蓝绿色(Teal) · 传达可靠/理性/真实/有趣
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700&family=Noto+Serif+SC:wght@400;600;700;900&display=swap');

:root {
  /* 主色系 - 蓝绿色 */
  --primary: #0d9488;
  --primary-dark: #134e4a;
  --primary-darker: #042f2e;
  --primary-light: #14b8a6;
  --primary-lighter: #5eead4;
  --primary-bg: #f0fdfa;
  --primary-bg-dark: #ccfbf1;

  /* 强调色 - 鲜亮金橙色 */
  --accent: #ff8c00;
  --accent-light: #ffb347;
  --accent-dark: #e67300;

  /* 中性色 */
  --text-dark: #0f172a;
  --text: #334155;
  --text-light: #64748b;
  --text-muted: #94a3b8;
  --bg: #fafafa;
  --bg-gray: #f1f5f9;
  --bg-dark: #0f172a;
  --white: #ffffff;
  --border: #e2e8f0;
  --border-light: #f1f5f9;

  /* 阴影 */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
  --shadow-primary: 0 10px 30px -10px rgba(13,148,136,0.4);

  /* 字体 */
  --font-serif: 'Noto Serif SC', serif;
  --font-sans: 'Noto Sans SC', sans-serif;

  /* 间距 */
  --section-padding: 6rem 2rem;
  --container-max: 1280px;

  /* 过渡 */
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 2rem;
}

/* ============================================
   滚动进度条
   ============================================ */
.scroll-progress {
  position: fixed;
  top: 0; left: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  z-index: 9999;
  transition: width 0.1s;
}

/* ============================================
   导航栏 - 透明→实色滚动
   ============================================ */
.main-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  padding: 1.5rem 2rem;
  transition: var(--transition-slow);
  background: transparent;
}
.main-nav.scrolled {
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(20px);
  box-shadow: var(--shadow);
  padding: 1rem 2rem;
}
.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--white);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition);
}
.main-nav.scrolled .nav-logo { color: var(--primary-dark); }
.nav-logo-icon {
  width: 36px; height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.1rem;
  font-weight: 700;
}
.nav-menu {
  display: flex;
  gap: 2.5rem;
  align-items: center;
}
.nav-menu a {
  color: rgba(255,255,255,0.9);
  font-size: 0.95rem;
  font-weight: 500;
  position: relative;
  transition: var(--transition);
  padding: 0.5rem 0;
}
.main-nav.scrolled .nav-menu a { color: var(--text); }
.nav-menu a::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  width: 0; height: 2px;
  background: var(--accent);
  transition: var(--transition);
}
.nav-menu a:hover::after,
.nav-menu a.active::after { width: 100%; }
.nav-menu a:hover,
.nav-menu a.active { color: var(--accent); }
.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: white;
  cursor: pointer;
}
.main-nav.scrolled .nav-toggle { color: var(--text-dark); }

/* ============================================
   全屏英雄区
   ============================================ */
.hero {
  position: relative;
  height: 100vh;
  min-height: 700px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  background: var(--primary-dark);
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  transform: scale(1.1);
  transition: transform 0.1s;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(4,47,46,0.25) 0%, rgba(4,47,46,0.45) 50%, rgba(4,47,46,0.75) 100%);
}
.hero-content {
  position: relative;
  z-index: 2;
  color: white;
  max-width: 900px;
  padding: 0 2rem;
}
.hero-tag {
  display: inline-block;
  padding: 0.5rem 1.5rem;
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 50px;
  font-size: 0.85rem;
  letter-spacing: 3px;
  text-transform: uppercase;
  margin-bottom: 2rem;
  backdrop-filter: blur(10px);
  background: rgba(255,255,255,0.05);
  animation: fadeInDown 1s ease;
}
.hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(2.5rem, 6vw, 5rem);
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 1.5rem;
  letter-spacing: -0.02em;
  animation: fadeInUp 1s ease 0.2s both;
}
.hero h1 .accent {
  background: linear-gradient(135deg, var(--accent-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.3rem);
  opacity: 0.95;
  line-height: 1.8;
  margin-bottom: 2.5rem;
  font-weight: 300;
  animation: fadeInUp 1s ease 0.4s both;
}
.hero-cta {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 1s ease 0.6s both;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 1rem 2.5rem;
  border-radius: 50px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  font-family: var(--font-sans);
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  box-shadow: var(--shadow-primary);
}
.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 15px 40px -10px rgba(13,148,136,0.5);
}
.btn-outline {
  background: transparent;
  color: white;
  border: 2px solid rgba(255,255,255,0.4);
}
.btn-outline:hover {
  background: white;
  color: var(--primary-dark);
  border-color: white;
}
.btn-gold {
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  color: var(--primary-darker);
  font-weight: 600;
}
.btn-gold:hover {
  transform: translateY(-3px);
  box-shadow: 0 15px 40px -10px rgba(212,175,55,0.5);
}
.hero-scroll {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  color: rgba(255,255,255,0.7);
  font-size: 0.8rem;
  letter-spacing: 2px;
  text-transform: uppercase;
  animation: bounce 2s infinite;
  z-index: 2;
}
.hero-scroll::after {
  content: '';
  display: block;
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, rgba(255,255,255,0.7), transparent);
  margin: 0.5rem auto 0;
}

/* ============================================
   大标题排版
   ============================================ */
.section-header {
  text-align: center;
  margin-bottom: 4rem;
}
.section-tag {
  display: inline-block;
  color: var(--primary);
  font-size: 0.85rem;
  letter-spacing: 4px;
  text-transform: uppercase;
  font-weight: 600;
  margin-bottom: 1rem;
}
.section-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 3.2rem);
  font-weight: 700;
  color: var(--text-dark);
  line-height: 1.2;
  margin-bottom: 1rem;
}
.section-desc {
  font-size: 1.1rem;
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.8;
}
.divider {
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  margin: 1.5rem auto;
  border-radius: 2px;
}

/* ============================================
   线条图标系统
   ============================================ */
.icon-line {
  width: 48px;
  height: 48px;
  stroke: var(--primary);
  stroke-width: 1.5;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
  transition: var(--transition);
}
.icon-box {
  width: 72px;
  height: 72px;
  border-radius: 20px;
  background: var(--primary-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  transition: var(--transition);
}
.icon-box:hover {
  background: var(--primary);
  transform: translateY(-5px);
}
.icon-box:hover .icon-line { stroke: white; }

/* ============================================
   滚动触发动画
   ============================================ */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.reveal.active {
  opacity: 1;
  transform: translateY(0);
}
.reveal-left {
  opacity: 0;
  transform: translateX(-60px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.reveal-left.active { opacity: 1; transform: translateX(0); }
.reveal-right {
  opacity: 0;
  transform: translateX(60px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.reveal-right.active { opacity: 1; transform: translateX(0); }
.reveal-scale {
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.reveal-scale.active { opacity: 1; transform: scale(1); }

/* ============================================
   分屏布局
   ============================================ */
.split-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: 80vh;
  align-items: center;
}
.split-image {
  position: relative;
  height: 100%;
  min-height: 500px;
  overflow: hidden;
}
.split-image img,
.split-image .img-placeholder {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 0;
}
.split-content {
  padding: 5rem 4rem;
}
.split-content .section-tag { text-align: left; }
.split-content h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.8rem, 3vw, 2.8rem);
  font-weight: 700;
  color: var(--text-dark);
  line-height: 1.25;
  margin-bottom: 1.5rem;
}
.split-content p {
  font-size: 1.05rem;
  color: var(--text-light);
  line-height: 1.9;
  margin-bottom: 1.5rem;
}

/* ============================================
   3D卡片悬停
   ============================================ */
.card-3d {
  background: white;
  border-radius: 24px;
  padding: 2.5rem;
  box-shadow: var(--shadow);
  transition: var(--transition-slow);
  transform-style: preserve-3d;
  position: relative;
  overflow: hidden;
  border: 1px solid var(--border-light);
}
.card-3d::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: scaleX(0);
  transition: var(--transition-slow);
}
.card-3d:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}
.card-3d:hover::before { transform: scaleX(1); }

/* ============================================
   四维板块大卡片
   ============================================ */
.pillar-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}
.pillar-card {
  position: relative;
  border-radius: 24px;
  overflow: hidden;
  height: 420px;
  cursor: pointer;
  transition: var(--transition-slow);
}
.pillar-card:hover { transform: translateY(-8px); }
.pillar-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  transition: var(--transition-slow);
}
.pillar-card:hover .pillar-bg { transform: scale(1.1); }
.pillar-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(4,47,46,0.95) 0%, rgba(13,148,136,0.4) 60%, transparent 100%);
}
.pillar-content {
  position: absolute;
  bottom: 0; left: 0; right: 0;
  padding: 2rem;
  color: white;
}
.pillar-number {
  font-family: var(--font-serif);
  font-size: 0.9rem;
  opacity: 0.7;
  letter-spacing: 3px;
  margin-bottom: 0.5rem;
}
.pillar-title {
  font-family: var(--font-serif);
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}
.pillar-subtitle {
  font-size: 0.9rem;
  opacity: 0.8;
  margin-bottom: 1rem;
}
.pillar-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--accent-light);
  font-weight: 500;
  opacity: 0;
  transform: translateY(10px);
  transition: var(--transition);
}
.pillar-card:hover .pillar-link {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   建筑探索器 - 交互切换
   ============================================ */
.explorer {
  background: var(--primary-darker);
  border-radius: 32px;
  overflow: hidden;
  display: grid;
  grid-template-columns: 300px 1fr;
  min-height: 600px;
}
.explorer-nav {
  background: rgba(255,255,255,0.03);
  border-right: 1px solid rgba(255,255,255,0.1);
  padding: 2rem 0;
}
.explorer-nav-item {
  padding: 1.2rem 2rem;
  color: rgba(255,255,255,0.6);
  cursor: pointer;
  transition: var(--transition);
  border-left: 3px solid transparent;
  display: flex;
  align-items: center;
  gap: 1rem;
}
.explorer-nav-item:hover {
  color: white;
  background: rgba(255,255,255,0.05);
}
.explorer-nav-item.active {
  color: var(--accent-light);
  background: rgba(212,175,55,0.08);
  border-left-color: var(--accent);
}
.explorer-nav-item .num {
  font-family: var(--font-serif);
  font-size: 0.8rem;
  opacity: 0.5;
}
.explorer-content {
  padding: 3rem;
  color: white;
  position: relative;
}
.explorer-panel {
  display: none;
  animation: fadeIn 0.5s ease;
}
.explorer-panel.active { display: block; }
.explorer-panel h3 {
  font-family: var(--font-serif);
  font-size: 2.2rem;
  margin-bottom: 0.5rem;
}
.explorer-panel .era {
  color: var(--accent-light);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
  letter-spacing: 1px;
}
.explorer-panel p {
  color: rgba(255,255,255,0.8);
  line-height: 1.9;
  margin-bottom: 1.5rem;
}
.explorer-image {
  width: 100%;
  height: 280px;
  border-radius: 16px;
  overflow: hidden;
  margin-top: 1.5rem;
}
.explorer-image img,
.explorer-image .img-placeholder {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ============================================
   数字统计区
   ============================================ */
.stats-section {
  background: linear-gradient(135deg, var(--primary-darker), var(--primary-dark));
  padding: var(--section-padding);
  color: white;
  position: relative;
  overflow: hidden;
}
.stats-section::before {
  content: '';
  position: absolute;
  top: -50%; right: -20%;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(13,148,136,0.3), transparent 70%);
  border-radius: 50%;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
  position: relative;
  z-index: 1;
}
.stat-item {
  text-align: center;
}
.stat-number {
  font-family: var(--font-serif);
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 900;
  background: linear-gradient(135deg, var(--accent-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 0.5rem;
}
.stat-label {
  font-size: 1rem;
  opacity: 0.8;
  letter-spacing: 1px;
}

/* ============================================
   时间轴
   ============================================ */
.timeline {
  position: relative;
  padding: 2rem 0;
}
.timeline::before {
  content: '';
  position: absolute;
  left: 50%;
  top: 0; bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--primary), var(--accent), var(--primary));
  transform: translateX(-50%);
}
.timeline-item {
  display: grid;
  grid-template-columns: 1fr 60px 1fr;
  align-items: center;
  margin-bottom: 3rem;
  gap: 2rem;
}
.timeline-item:nth-child(even) .timeline-content { order: 3; text-align: left; }
.timeline-item:nth-child(even) .timeline-dot { order: 2; }
.timeline-item:nth-child(even) .timeline-empty { order: 1; }
.timeline-dot {
  width: 60px; height: 60px;
  border-radius: 50%;
  background: white;
  border: 3px solid var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--primary);
  font-size: 0.85rem;
  z-index: 1;
  box-shadow: 0 0 0 8px rgba(13,148,136,0.1);
  transition: var(--transition);
}
.timeline-item:hover .timeline-dot {
  background: var(--primary);
  color: white;
  transform: scale(1.1);
}
.timeline-content {
  padding: 1.5rem;
  background: white;
  border-radius: 16px;
  box-shadow: var(--shadow);
  text-align: right;
  transition: var(--transition);
}
.timeline-item:hover .timeline-content {
  box-shadow: var(--shadow-lg);
  transform: translateY(-3px);
}
.timeline-year {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 0.3rem;
}
.timeline-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 0.5rem;
}
.timeline-desc {
  font-size: 0.9rem;
  color: var(--text-light);
  line-height: 1.7;
}

/* ============================================
   大图展示区
   ============================================ */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}
.gallery-item {
  position: relative;
  border-radius: 16px;
  overflow: hidden;
  aspect-ratio: 4/3;
  cursor: pointer;
}
.gallery-item.large { grid-column: span 2; grid-row: span 2; aspect-ratio: auto; }
.gallery-item.wide { grid-column: span 2; aspect-ratio: auto; }
.gallery-item.tall { grid-row: span 2; aspect-ratio: auto; }
.gallery-item img,
.gallery-item .img-placeholder {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition-slow);
}
.gallery-item:hover img,
.gallery-item:hover .img-placeholder { transform: scale(1.08); }
.gallery-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(4,47,46,0.9), transparent 60%);
  display: flex;
  align-items: flex-end;
  padding: 1.5rem;
  opacity: 0;
  transition: var(--transition);
}
.gallery-item:hover .gallery-overlay { opacity: 1; }
.gallery-info { color: white; }
.gallery-info h4 {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  margin-bottom: 0.3rem;
}
.gallery-info p { font-size: 0.85rem; opacity: 0.8; }

/* ============================================
   图片占位符
   ============================================ */
.img-placeholder {
  width: 100%;
  min-height: 200px;
  background: linear-gradient(135deg, var(--bg-gray), var(--primary-bg));
  border: 2px dashed var(--border);
  border-radius: 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1.5rem;
  color: var(--text-muted);
  font-size: 0.85rem;
  transition: var(--transition);
}
.img-placeholder:hover {
  border-color: var(--primary);
  background: var(--primary-bg);
}
.img-placeholder .icon {
  font-size: 2rem;
  margin-bottom: 0.5rem;
  opacity: 0.5;
}
.img-placeholder b {
  color: var(--text-light);
  display: block;
  margin-bottom: 0.3rem;
}
.img-placeholder .desc {
  font-size: 0.75rem;
  line-height: 1.5;
  max-width: 300px;
}

/* ============================================
   回到顶部
   ============================================ */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  box-shadow: var(--shadow-primary);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: var(--transition);
  z-index: 999;
}
.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.back-to-top:hover {
  background: var(--primary-dark);
  transform: translateY(-3px);
}

/* ============================================
   AI导览浮窗
   ============================================ */
.ai-guide {
  position: fixed;
  bottom: 2rem;
  left: 2rem;
  z-index: 999;
}
.ai-guide-btn {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  border: none;
  cursor: pointer;
  font-size: 1.5rem;
  box-shadow: var(--shadow-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  animation: pulse 2s infinite;
}
.ai-guide-btn:hover { transform: scale(1.1); }
.ai-guide-panel {
  position: absolute;
  bottom: 75px;
  left: 0;
  width: 340px;
  background: white;
  border-radius: 20px;
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: var(--transition);
}
.ai-guide-panel.open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.ai-guide-header {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: white;
  padding: 1.2rem;
  display: flex;
  align-items: center;
  gap: 0.8rem;
}
.ai-guide-avatar {
  width: 40px; height: 40px;
  border-radius: 50%;
  background: rgba(255,255,255,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
}
.ai-guide-header h4 { font-size: 1rem; margin-bottom: 0.1rem; }
.ai-guide-header p { font-size: 0.75rem; opacity: 0.8; }
.ai-guide-body { padding: 1rem; max-height: 350px; overflow-y: auto; scrollbar-width: none; -ms-overflow-style: none; }
.ai-guide-body::-webkit-scrollbar { display: none; }
.ai-question {
  padding: 0.8rem 1rem;
  background: var(--primary-bg);
  border-radius: 12px;
  margin-bottom: 0.5rem;
  cursor: pointer;
  font-size: 0.9rem;
  color: var(--text);
  transition: var(--transition);
  border: 1px solid transparent;
}
.ai-question:hover {
  background: var(--primary-bg-dark);
  border-color: var(--primary-lighter);
  color: var(--primary-dark);
}
.ai-answer {
  padding: 1rem;
  background: var(--bg-gray);
  border-radius: 12px;
  margin-top: 0.5rem;
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--text);
  display: none;
  animation: fadeIn 0.3s ease;
}
.ai-answer.show { display: block; }

/* ============================================
   页脚
   ============================================ */
.main-footer {
  background: var(--primary-darker);
  color: rgba(255,255,255,0.7);
  padding: 4rem 2rem 0;
}
.footer-container {
  max-width: var(--container-max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  padding-bottom: 3rem;
}
.footer-brand h3 {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  color: white;
  margin-bottom: 1rem;
}
.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.8;
  margin-bottom: 1.5rem;
}
.footer-links h4 {
  color: white;
  font-size: 1rem;
  margin-bottom: 1.2rem;
  font-weight: 600;
}
.footer-links ul li {
  margin-bottom: 0.7rem;
}
.footer-links a {
  font-size: 0.9rem;
  transition: var(--transition);
}
.footer-links a:hover { color: var(--accent-light); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 1.5rem 2rem;
  text-align: center;
  font-size: 0.85rem;
  max-width: var(--container-max);
  margin: 0 auto;
}

/* ============================================
   动画
   ============================================ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeInDown {
  from { opacity: 0; transform: translateY(-20px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(-10px); }
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(13,148,136,0.4); }
  50% { box-shadow: 0 0 0 15px rgba(13,148,136,0); }
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-15px); }
}
@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

/* ============================================
   响应式
   ============================================ */
/* ============================================
   横向无缝滚动画廊
   ============================================ */
.scroll-gallery {
  overflow: hidden;
  border-radius: 16px;
  height: 260px;
  position: relative;
  border: 2px dashed var(--border);
  background: linear-gradient(135deg, var(--bg-gray), var(--primary-bg));
}
.scroll-gallery::before,
.scroll-gallery::after {
  content: '';
  position: absolute;
  top: 0; bottom: 0;
  width: 60px;
  z-index: 2;
  pointer-events: none;
}
.scroll-gallery::before {
  left: 0;
  background: linear-gradient(to right, var(--bg-gray), transparent);
}
.scroll-gallery::after {
  right: 0;
  background: linear-gradient(to left, var(--bg-gray), transparent);
}
.scroll-gallery-track {
  display: flex;
  animation: scrollGallery 30s linear infinite;
  width: max-content;
  height: 100%;
  align-items: center;
}
.scroll-gallery:hover .scroll-gallery-track {
  animation-play-state: paused;
}
.scroll-gallery-item {
  flex-shrink: 0;
  width: 320px;
  height: 220px;
  margin: 0 0.75rem;
  border-radius: 12px;
  overflow: hidden;
  background: white;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1rem;
  transition: transform 0.3s;
}
.scroll-gallery-item:hover {
  transform: scale(1.03);
}
.scroll-gallery-item .sg-icon {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
  opacity: 0.7;
}
.scroll-gallery-item .sg-title {
  font-weight: 600;
  color: var(--text-dark);
  font-size: 0.95rem;
  margin-bottom: 0.3rem;
}
.scroll-gallery-item .sg-desc {
  font-size: 0.75rem;
  color: var(--text-light);
  line-height: 1.5;
}
@keyframes scrollGallery {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

@media (max-width: 1024px) {
  .pillar-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 3rem; }
  .footer-container { grid-template-columns: 1fr 1fr; }
  .explorer { grid-template-columns: 1fr; }
  .explorer-nav {
    display: flex;
    overflow-x: auto;
    border-right: none;
    border-bottom: 1px solid rgba(255,255,255,0.1);
    padding: 1rem;
  }
  .explorer-nav-item {
    border-left: none;
    border-bottom: 3px solid transparent;
    white-space: nowrap;
    padding: 0.8rem 1.2rem;
  }
  .explorer-nav-item.active {
    border-left: none;
    border-bottom-color: var(--accent);
  }
}

@media (max-width: 768px) {
  .nav-menu {
    position: fixed;
    top: 0; right: -100%;
    width: 80%;
    max-width: 300px;
    height: 100vh;
    background: var(--primary-darker);
    flex-direction: column;
    padding: 5rem 2rem;
    gap: 1.5rem;
    transition: right 0.3s ease;
  }
  .nav-menu.open { right: 0; }
  .nav-menu a { color: white; font-size: 1.1rem; }
  .nav-toggle { display: block; }
  .split-section { grid-template-columns: 1fr; }
  .split-image { min-height: 350px; }
  .split-content { padding: 3rem 1.5rem; }
  .pillar-grid { grid-template-columns: 1fr; }
  .pillar-card { height: 320px; }
  .gallery-grid { grid-template-columns: 1fr; }
  .gallery-item.large { grid-column: span 1; grid-row: span 1; }
  .timeline::before { left: 30px; }
  .timeline-item {
    grid-template-columns: 60px 1fr;
    gap: 1rem;
  }
  .timeline-empty { display: none; }
  .timeline-content,
  .timeline-item:nth-child(even) .timeline-content {
    text-align: left;
    order: 2;
  }
  .timeline-dot,
  .timeline-item:nth-child(even) .timeline-dot { order: 1; }
  .stats-grid { grid-template-columns: 1fr 1fr; gap: 2rem; }
  .footer-container { grid-template-columns: 1fr; gap: 2rem; }
  .ai-guide-panel { width: calc(100vw - 4rem); left: 0; }
  .hero-cta { flex-direction: column; align-items: center; }
  .btn { width: 100%; max-width: 280px; justify-content: center; }
}

@media (max-width: 480px) {
  .stats-grid { grid-template-columns: 1fr; }
  .section-padding { padding: 4rem 1rem; }
}

/* ============================================
   暗色模式
   ============================================ */
body.dark-mode {
  --text-dark: #f1f5f9;
  --text: #cbd5e1;
  --text-light: #94a3b8;
  --text-muted: #64748b;
  --bg: #0f172a;
  --bg-gray: #1e293b;
  --bg-dark: #020617;
  --white: #1e293b;
  --border: #334155;
  --border-light: #1e293b;
  --primary-bg: #134e4a;
  --primary-bg-dark: #042f2e;
}
body.dark-mode .card-3d { background: #1e293b; border-color: #334155; }
body.dark-mode .archive-item { background: #134e4a; }
body.dark-mode .img-placeholder { background: linear-gradient(135deg, #1e293b, #134e4a); border-color: #334155; }
body.dark-mode .ai-guide-panel { background: #1e293b; }
body.dark-mode .ai-question { background: #134e4a; color: #cbd5e1; }
body.dark-mode .ai-question:hover { background: #042f2e; color: #5eead4; }
body.dark-mode .ai-answer { background: #0f172a; color: #cbd5e1; }
body.dark-mode .breadcrumb { background: rgba(15,23,42,0.95); }
body.dark-mode .explorer { background: #042f2e; }
body.dark-mode .scroll-gallery { background: linear-gradient(135deg, #1e293b, #134e4a); border-color: #334155; }
body.dark-mode .scroll-gallery-item { background: #1e293b; }
body.dark-mode .modal-content { background: #1e293b; }
body.dark-mode input, body.dark-mode textarea, body.dark-mode select {
  background: #0f172a; color: #f1f5f9; border-color: #334155;
}
body.dark-mode .modal-overlay { background: rgba(0,0,0,0.7); }

/* 导航栏图标按钮（搜索/暗色模式） */
.nav-icon-btn {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  line-height: 1;
  color: rgba(255,255,255,0.9);
}
.main-nav.scrolled .nav-icon-btn { color: var(--text); }
.nav-icon-btn:hover { color: var(--accent); }
.theme-toggle { /* 复用 nav-icon-btn 样式，不再固定定位 */ }

/* ============================================
   全站搜索
   ============================================ */
.search-toggle {
  background: none;
  border: none;
  color: inherit;
  cursor: pointer;
  font-size: 1.1rem;
  padding: 0.5rem;
  transition: var(--transition);
  display: flex;
  align-items: center;
}
.search-toggle:hover { color: var(--accent); }
.search-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(4,47,46,0.95);
  backdrop-filter: blur(10px);
  z-index: 2000;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 15vh;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
  overflow: hidden;
}
.search-overlay.open { opacity: 1; visibility: visible; }
.search-close {
  position: absolute;
  top: 2rem;
  right: 2rem;
  background: none;
  border: none;
  color: white;
  font-size: 2rem;
  cursor: pointer;
  opacity: 0.7;
  transition: opacity 0.3s;
}
.search-close:hover { opacity: 1; }
.search-box {
  width: 90%;
  max-width: 600px;
  position: relative;
}
.search-box input {
  width: 100%;
  padding: 1.2rem 1.5rem 1.2rem 3.5rem;
  font-size: 1.2rem;
  border: 2px solid rgba(255,255,255,0.2);
  border-radius: 50px;
  background: rgba(255,255,255,0.1);
  color: white;
  outline: none;
  transition: border-color 0.3s;
  font-family: var(--font-sans);
}
.search-box input::placeholder { color: rgba(255,255,255,0.5); }
.search-box input:focus { border-color: var(--accent); }
.search-box .search-icon {
  position: absolute;
  left: 1.2rem;
  top: 50%;
  transform: translateY(-50%);
  color: rgba(255,255,255,0.6);
  font-size: 1.2rem;
}
.search-results {
  width: 90%;
  max-width: 600px;
  margin-top: 1.5rem;
  max-height: 50vh;
  overflow-y: auto;
  overflow-x: hidden;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.search-results::-webkit-scrollbar { display: none; width: 0; height: 0; }
.search-result-item {
  padding: 1rem 1.5rem;
  background: rgba(255,255,255,0.08);
  border-radius: 12px;
  margin-bottom: 0.8rem;
  cursor: pointer;
  transition: all 0.3s;
  border: 1px solid transparent;
}
.search-result-item:hover {
  background: rgba(255,255,255,0.15);
  border-color: var(--accent);
  transform: translateX(5px);
}
.search-result-item .result-title {
  color: white;
  font-weight: 600;
  font-size: 1rem;
  margin-bottom: 0.3rem;
}
.search-result-item .result-desc {
  color: rgba(255,255,255,0.6);
  font-size: 0.85rem;
}
.search-result-item .result-tag {
  display: inline-block;
  padding: 0.15rem 0.6rem;
  background: var(--accent);
  color: var(--primary-darker);
  border-radius: 20px;
  font-size: 0.7rem;
  font-weight: 600;
  margin-left: 0.5rem;
}
.search-no-result {
  text-align: center;
  color: rgba(255,255,255,0.5);
  padding: 2rem;
}
.search-hint {
  color: rgba(255,255,255,0.4);
  font-size: 0.85rem;
  margin-top: 1rem;
  text-align: center;
}

/* ============================================
   UGC留言墙
   ============================================ */
.message-wall {
  padding: var(--section-padding);
  background: var(--bg-gray);
}
.message-wall-container { max-width: 900px; margin: 0 auto; }
.message-form {
  background: white;
  border-radius: 20px;
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
}
body.dark-mode .message-form { background: #1e293b; }
.message-form textarea {
  width: 100%;
  min-height: 100px;
  padding: 1rem;
  border: 2px solid var(--border);
  border-radius: 12px;
  font-size: 1rem;
  font-family: var(--font-sans);
  resize: vertical;
  outline: none;
  transition: border-color 0.3s;
  line-height: 1.7;
}
.message-form textarea:focus { border-color: var(--primary); }
.message-form-row {
  display: flex;
  gap: 1rem;
  margin-top: 1rem;
  flex-wrap: wrap;
}
.message-form input {
  flex: 1;
  min-width: 150px;
  padding: 0.7rem 1rem;
  border: 2px solid var(--border);
  border-radius: 12px;
  font-size: 0.95rem;
  font-family: var(--font-sans);
  outline: none;
  transition: border-color 0.3s;
}
.message-form input:focus { border-color: var(--primary); }
.message-submit {
  padding: 0.7rem 2rem;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  border: none;
  border-radius: 50px;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  font-family: var(--font-sans);
}
.message-submit:hover { transform: translateY(-2px); box-shadow: var(--shadow-primary); }
.message-list { display: flex; flex-direction: column; gap: 1rem; }
.message-item {
  background: white;
  border-radius: 16px;
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  border-left: 4px solid var(--primary);
  animation: fadeInUp 0.5s ease;
}
body.dark-mode .message-item { background: #1e293b; }
.message-item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.8rem;
}
.message-author {
  font-weight: 600;
  color: var(--text-dark);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.message-avatar {
  width: 32px; height: 32px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 700;
}
.message-date { font-size: 0.8rem; color: var(--text-muted); }
.message-content {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--text);
}
.message-empty {
  text-align: center;
  padding: 3rem;
  color: var(--text-muted);
  font-size: 1rem;
}

/* ============================================
   建筑数据库页面
   ============================================ */
.db-hero {
  position: relative;
  height: 50vh;
  min-height: 350px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  background: linear-gradient(135deg, var(--primary-darker), var(--primary-dark));
  margin-top: 70px;
}
.db-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 30% 50%, rgba(13,148,136,0.3), transparent 50%),
              radial-gradient(circle at 70% 50%, rgba(255,140,0,0.15), transparent 50%);
}
.db-hero-content { position: relative; z-index: 2; color: white; padding: 0 2rem; }
.db-hero h1 { font-family: var(--font-serif); font-size: clamp(2rem, 5vw, 3.5rem); font-weight: 900; margin-bottom: 1rem; }
.db-hero p { font-size: 1.1rem; opacity: 0.85; max-width: 600px; margin: 0 auto; }
.db-filters {
  padding: 2rem;
  background: white;
  border-bottom: 1px solid var(--border-light);
  position: sticky;
  top: 70px;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}
body.dark-mode .db-filters { background: #1e293b; }
.db-filters-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  align-items: center;
}
.db-filter-btn {
  padding: 0.5rem 1.2rem;
  border: 2px solid var(--border);
  border-radius: 50px;
  background: transparent;
  color: var(--text);
  font-size: 0.9rem;
  cursor: pointer;
  transition: all 0.3s;
  font-family: var(--font-sans);
}
.db-filter-btn:hover { border-color: var(--primary); color: var(--primary); }
.db-filter-btn.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}
.db-search {
  flex: 1;
  min-width: 200px;
  position: relative;
}
.db-search input {
  width: 100%;
  padding: 0.6rem 1rem 0.6rem 2.5rem;
  border: 2px solid var(--border);
  border-radius: 50px;
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.3s;
  font-family: var(--font-sans);
}
.db-search input:focus { border-color: var(--primary); }
.db-search .icon { position: absolute; left: 0.8rem; top: 50%; transform: translateY(-50%); color: var(--text-muted); }
.db-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  padding: 3rem 2rem;
  max-width: 1280px;
  margin: 0 auto;
}
.db-card {
  background: white;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition-slow);
  cursor: pointer;
  border: 1px solid var(--border-light);
}
body.dark-mode .db-card { background: #1e293b; border-color: #334155; }
.db-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-xl); }
.db-card-image {
  height: 180px;
  background-size: cover;
  background-position: center;
  position: relative;
}
.db-card-tag {
  position: absolute;
  top: 1rem;
  left: 1rem;
  padding: 0.3rem 0.8rem;
  background: rgba(255,255,255,0.9);
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--primary-dark);
}
.db-card-body { padding: 1.5rem; }
.db-card-title {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 0.5rem;
}
.db-card-meta {
  display: flex;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 0.8rem;
  flex-wrap: wrap;
}
.db-card-desc {
  font-size: 0.9rem;
  color: var(--text-light);
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.db-stats {
  display: flex;
  gap: 2rem;
  justify-content: center;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}
.db-stat { text-align: center; color: rgba(255,255,255,0.9); }
.db-stat-num { font-family: var(--font-serif); font-size: 2rem; font-weight: 900; color: var(--accent-light); }
.db-stat-label { font-size: 0.85rem; opacity: 0.7; }

/* ============================================
   弹窗通用样式
   ============================================ */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  backdrop-filter: blur(5px);
  z-index: 3000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
  padding: 2rem;
}
.modal-overlay.open { opacity: 1; visibility: visible; }
.modal-content {
  background: white;
  border-radius: 24px;
  max-width: 500px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  padding: 2.5rem;
  position: relative;
  transform: scale(0.9) translateY(20px);
  transition: transform 0.3s;
  box-shadow: var(--shadow-xl);
}
.modal-overlay.open .modal-content { transform: scale(1) translateY(0); }
.modal-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-muted);
  transition: color 0.3s;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
}
.modal-close:hover { color: var(--text-dark); background: var(--bg-gray); }
.modal-title {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 0.5rem;
}
.modal-desc { font-size: 0.95rem; color: var(--text-light); margin-bottom: 1.5rem; line-height: 1.7; }
.form-group { margin-bottom: 1.2rem; }
.form-group label {
  display: block;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-dark);
  margin-bottom: 0.5rem;
}
.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 0.7rem 1rem;
  border: 2px solid var(--border);
  border-radius: 12px;
  font-size: 0.95rem;
  font-family: var(--font-sans);
  outline: none;
  transition: border-color 0.3s;
}
.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus { border-color: var(--primary); }
.form-group textarea { resize: vertical; min-height: 80px; }
.rating-group { display: flex; gap: 0.8rem; justify-content: center; padding: 0.5rem 0; }
.rating-option {
  display: flex;
  flex-direction: column;
  align-items: center;
  cursor: pointer;
  gap: 0.3rem;
}
.rating-dot {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 2px solid var(--border);
  transition: all 0.3s;
  display: flex;
  align-items: center;
  justify-content: center;
}
.rating-option input { display: none; }
.rating-option input:checked + .rating-dot {
  background: var(--primary);
  border-color: var(--primary);
}
.rating-option input:checked + .rating-dot::after {
  content: '';
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: white;
}
.rating-label { font-size: 0.75rem; color: var(--text-muted); }
.form-error {
  color: #ef4444;
  font-size: 0.85rem;
  margin-top: 0.3rem;
  display: none;
}
.form-error.show { display: block; }
.form-success {
  text-align: center;
  padding: 2rem;
}
.form-success-icon {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  margin: 0 auto 1rem;
  animation: scaleIn 0.5s ease;
}
@keyframes scaleIn {
  from { transform: scale(0); }
  to { transform: scale(1); }
}
.form-success h3 { font-family: var(--font-serif); font-size: 1.3rem; color: var(--text-dark); margin-bottom: 0.5rem; }
.form-success p { color: var(--text-light); font-size: 0.95rem; }

/* ============================================
   全局动效 - 滚动入场/视差/数字滚动
   ============================================ */

/* 滚动入场动画 */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal.active {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }

/* 从左侧滑入 */
.reveal-left {
  opacity: 0;
  transform: translateX(-40px);
  transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal-left.active {
  opacity: 1;
  transform: translateX(0);
}

/* 从右侧滑入 */
.reveal-right {
  opacity: 0;
  transform: translateX(40px);
  transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal-right.active {
  opacity: 1;
  transform: translateX(0);
}

/* 缩放进入 */
.reveal-scale {
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}
.reveal-scale.active {
  opacity: 1;
  transform: scale(1);
}

/* 视差背景 */
.parallax-bg {
  background-attachment: fixed;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}
.parallax-element {
  will-change: transform;
  transition: transform 0.1s linear;
}

/* 数字滚动 */
.count-up {
  display: inline-block;
  font-variant-numeric: tabular-nums;
}

/* 卡片悬停精致效果 */
.card-hover {
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.card-hover:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(0,0,0,0.12);
}

/* 首屏建筑线稿动画 */
.hero-lineart {
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  max-width: 900px;
  height: auto;
  opacity: 0.15;
  pointer-events: none;
  z-index: 1;
}
.hero-lineart path,
.hero-lineart line,
.hero-lineart polyline,
.hero-lineart rect,
.hero-lineart circle {
  stroke-dasharray: 2000;
  stroke-dashoffset: 2000;
  animation: drawLine 3s ease-in-out forwards;
}
.hero-lineart path:nth-child(2),
.hero-lineart line:nth-child(2) { animation-delay: 0.3s; }
.hero-lineart path:nth-child(3),
.hero-lineart line:nth-child(3) { animation-delay: 0.6s; }
.hero-lineart path:nth-child(4),
.hero-lineart line:nth-child(4) { animation-delay: 0.9s; }
.hero-lineart path:nth-child(5),
.hero-lineart line:nth-child(5) { animation-delay: 1.2s; }

@keyframes drawLine {
  to { stroke-dashoffset: 0; }
}

/* 文字逐行淡入 */
.text-fade-in > * {
  opacity: 0;
  transform: translateY(20px);
  animation: textFadeIn 0.8s ease-out forwards;
}
.text-fade-in > *:nth-child(1) { animation-delay: 0.2s; }
.text-fade-in > *:nth-child(2) { animation-delay: 0.5s; }
.text-fade-in > *:nth-child(3) { animation-delay: 0.8s; }
.text-fade-in > *:nth-child(4) { animation-delay: 1.1s; }
.text-fade-in > *:nth-child(5) { animation-delay: 1.4s; }

@keyframes textFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 页面内浮动导航 */
.page-toc {
  position: fixed;
  right: 2rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.page-toc a {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(13,148,136,0.3);
  transition: all 0.3s;
  position: relative;
}
.page-toc a:hover,
.page-toc a.active {
  background: var(--primary);
  transform: scale(1.4);
}
.page-toc a:hover::after {
  content: attr(data-label);
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  white-space: nowrap;
  background: var(--primary-dark);
  color: white;
  padding: 0.3rem 0.8rem;
  border-radius: 6px;
  font-size: 0.8rem;
}
@media (max-width: 1024px) {
  .page-toc { display: none; }
  .parallax-bg { background-attachment: scroll; }
}

   建筑音频讲解播放器
   ============================================ */
.audio-guide {
  margin-top: 1.2rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}
.audio-play-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.7rem 1.5rem;
  background: rgba(212,175,55,0.18);
  border: 1px solid rgba(212,175,55,0.45);
  border-radius: 50px;
  color: #fde68a;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all 0.3s;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  align-self: flex-start;
  font-family: inherit;
  font-weight: 500;
}
.audio-play-btn:hover {
  background: rgba(212,175,55,0.32);
  transform: translateY(-2px);
  box-shadow: 0 4px 20px rgba(212,175,55,0.25);
}
.audio-play-btn.playing {
  background: rgba(212,175,55,0.38);
}
.audio-icon {
  font-size: 1.05rem;
  display: inline-flex;
  align-items: center;
}
.audio-text {
  letter-spacing: 0.03em;
}
.audio-progress {
  display: none;
  align-items: center;
  gap: 0.8rem;
  width: 100%;
  max-width: 420px;
}
.audio-progress.show {
  display: flex;
}
.audio-progress-bar-container {
  flex: 1;
  height: 4px;
  background: rgba(255,255,255,0.2);
  border-radius: 2px;
  cursor: pointer;
  overflow: hidden;
}
.audio-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, #d4af37, #fbbf24);
  border-radius: 2px;
  width: 0%;
  transition: width 0.1s linear;
}
.audio-time {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.7);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}