/* ===== 全局变量 ===== */
:root {
  --primary: #003366;
  --primary-light: #0066cc;
  --accent: #00a8e8;
  --bg-light: #f6f8fb;
  --bg-card: #ffffff;
  --text-main: #1a2332;
  --text-muted: #5a6878;
  --border: #e1e8f0;
  --shadow: 0 2px 12px rgba(0, 51, 102, 0.08);
  --shadow-hover: 0 6px 24px rgba(0, 51, 102, 0.15);
  --radius: 8px;
  --max-width: 1200px;
  --nav-height: 64px;
}

/* ===== 基础重置 ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", "Helvetica Neue", Arial, sans-serif;
  color: var(--text-main);
  background: var(--bg-light);
  line-height: 1.7;
  font-size: 16px;
}

a {
  color: var(--primary-light);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: var(--accent);
}

img {
  max-width: 100%;
  display: block;
}

/* ===== 顶部导航 ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(0, 51, 102, 0.96);
  backdrop-filter: blur(8px);
  z-index: 1000;
  display: flex;
  align-items: center;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  color: #fff;
  font-size: 18px;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.nav-brand .brand-sub {
  font-size: 12px;
  font-weight: 400;
  opacity: 0.85;
  display: block;
  margin-top: 2px;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 4px;
}

.nav-menu a {
  color: rgba(255, 255, 255, 0.85);
  padding: 8px 14px;
  border-radius: 4px;
  font-size: 14px;
  transition: all 0.2s;
}

.nav-menu a:hover,
.nav-menu a.active {
  color: #fff;
  background: rgba(255, 255, 255, 0.12);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  font-size: 24px;
  cursor: pointer;
  padding: 4px 8px;
}

/* ===== Hero 区 ===== */
.hero {
  position: relative;
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #fff;
  padding: calc(var(--nav-height) + 60px) 24px 60px;
  background: linear-gradient(135deg, #003366 0%, #0066cc 50%, #00a8e8 100%);
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: 
    radial-gradient(circle at 20% 30%, rgba(255,255,255,0.08) 0%, transparent 40%),
    radial-gradient(circle at 80% 70%, rgba(255,255,255,0.06) 0%, transparent 40%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 900px;
}

.hero-date {
  font-size: 16px;
  letter-spacing: 2px;
  margin-bottom: 16px;
  opacity: 0.9;
}

.hero-title {
  font-size: 44px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 12px;
  text-shadow: 0 2px 20px rgba(0,0,0,0.2);
}

.hero-subtitle {
  font-size: 18px;
  opacity: 0.9;
  margin-bottom: 28px;
  font-style: italic;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 24px;
  margin-top: 32px;
  font-size: 15px;
}

.hero-meta span {
  background: rgba(255, 255, 255, 0.12);
  padding: 8px 18px;
  border-radius: 20px;
  backdrop-filter: blur(4px);
}

/* ===== 通用容器 ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 60px 24px;
}

.section {
  padding: 60px 0;
}

.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  font-size: 32px;
  color: var(--primary);
  font-weight: 600;
  position: relative;
  display: inline-block;
  padding-bottom: 16px;
}

.section-title h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: var(--accent);
  border-radius: 2px;
}

.section-title p {
  color: var(--text-muted);
  margin-top: 12px;
  font-size: 15px;
}

/* ===== 数据卡片 ===== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 24px;
}

.stat-card {
  background: var(--bg-card);
  padding: 28px 20px;
  border-radius: var(--radius);
  text-align: center;
  box-shadow: var(--shadow);
  transition: transform 0.25s, box-shadow 0.25s;
  border-top: 3px solid var(--accent);
}

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.stat-number {
  font-size: 36px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.2;
}

.stat-label {
  color: var(--text-muted);
  font-size: 14px;
  margin-top: 8px;
}

/* ===== 卡片网格 ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

.card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: transform 0.25s, box-shadow 0.25s;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.card-body {
  padding: 24px;
}

.card-title {
  font-size: 18px;
  color: var(--primary);
  margin-bottom: 10px;
  font-weight: 600;
}

.card-text {
  color: var(--text-muted);
  font-size: 14px;
}

/* ===== 表格 ===== */
.table-wrap {
  overflow-x: auto;
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

table th {
  background: var(--primary);
  color: #fff;
  padding: 14px 16px;
  text-align: left;
  font-weight: 600;
}

table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  color: var(--text-main);
}

table tr:hover td {
  background: var(--bg-light);
}

table tr:last-child td {
  border-bottom: none;
}

/* ===== 时间线 ===== */
.timeline {
  position: relative;
  padding-left: 32px;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  margin-bottom: 32px;
  padding: 20px 24px;
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 24px;
  width: 14px;
  height: 14px;
  background: var(--accent);
  border: 3px solid #fff;
  border-radius: 50%;
  box-shadow: 0 0 0 2px var(--accent);
}

.timeline-date {
  color: var(--primary-light);
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 6px;
}

.timeline-title {
  font-size: 18px;
  color: var(--primary);
  margin-bottom: 8px;
}

/* ===== 嘉宾卡片 ===== */
.speaker-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  text-align: center;
  transition: transform 0.25s, box-shadow 0.25s;
  border-left: 4px solid var(--primary-light);
}

.speaker-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.speaker-avatar {
  width: 80px;
  height: 80px;
  margin: 0 auto 16px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 24px;
  font-weight: 600;
}

.speaker-name {
  font-size: 17px;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 4px;
}

.speaker-title {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 8px;
  min-height: 36px;
}

.speaker-org {
  font-size: 13px;
  color: var(--primary-light);
  margin-bottom: 10px;
}

.speaker-role {
  display: inline-block;
  font-size: 12px;
  background: var(--bg-light);
  color: var(--primary);
  padding: 4px 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
}

/* ===== 照片墙 ===== */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 16px;
}

.gallery-item {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius);
  cursor: pointer;
  aspect-ratio: 4/3;
  background: var(--bg-light);
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s;
}

.gallery-item:hover img {
  transform: scale(1.06);
}

.gallery-item::after {
  content: "🔍";
  position: absolute;
  inset: 0;
  background: rgba(0, 51, 102, 0.4);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  opacity: 0;
  transition: opacity 0.3s;
}

.gallery-item:hover::after {
  opacity: 1;
}

/* ===== 灯箱 ===== */
.lightbox {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.9);
  z-index: 2000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 40px;
}

.lightbox.active {
  display: flex;
}

.lightbox img {
  max-width: 90%;
  max-height: 90vh;
  border-radius: 4px;
}

.lightbox-close {
  position: absolute;
  top: 24px;
  right: 32px;
  color: #fff;
  font-size: 36px;
  cursor: pointer;
  line-height: 1;
}

.lightbox-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  color: #fff;
  font-size: 48px;
  cursor: pointer;
  padding: 16px;
  user-select: none;
}

.lightbox-prev { left: 24px; }
.lightbox-next { right: 24px; }

/* ===== 引用块 ===== */
.quote-block {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
  color: #fff;
  padding: 40px;
  border-radius: var(--radius);
  margin: 32px 0;
  position: relative;
  overflow: hidden;
}

.quote-block::before {
  content: """;
  position: absolute;
  top: -20px;
  left: 20px;
  font-size: 120px;
  opacity: 0.15;
  font-family: Georgia, serif;
  line-height: 1;
}

.quote-block p {
  position: relative;
  font-size: 18px;
  font-style: italic;
  margin-bottom: 12px;
}

.quote-block .quote-author {
  font-size: 14px;
  opacity: 0.9;
  text-align: right;
}

/* ===== 媒体卡片 ===== */
.media-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform 0.25s, box-shadow 0.25s;
}

.media-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.media-source {
  background: var(--primary);
  color: #fff;
  padding: 8px 20px;
  font-size: 13px;
  font-weight: 600;
}

.media-body {
  padding: 20px;
  flex: 1;
}

.media-title {
  font-size: 16px;
  color: var(--primary);
  margin-bottom: 10px;
  font-weight: 600;
  line-height: 1.5;
}

.media-summary {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 14px;
}

.media-meta {
  font-size: 12px;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  padding-top: 12px;
}

.video-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
  margin-top: 24px;
}

.video-item {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
  transition: transform 0.25s;
  border-left: 4px solid var(--accent);
}

.video-item:hover {
  transform: translateX(4px);
}

.video-icon {
  width: 44px;
  height: 44px;
  background: var(--bg-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}

.video-info {
  flex: 1;
  min-width: 0;
}

.video-source {
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 2px;
}

.video-title {
  font-size: 14px;
  color: var(--primary);
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ===== 数据可视化 ===== */
.chart-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px;
  margin-bottom: 24px;
}

.chart-title {
  font-size: 18px;
  color: var(--primary);
  margin-bottom: 20px;
  font-weight: 600;
}

.bar-chart {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.bar-item {
  display: grid;
  grid-template-columns: 160px 1fr 60px;
  align-items: center;
  gap: 12px;
  font-size: 14px;
}

.bar-label {
  color: var(--text-main);
}

.bar-track {
  background: var(--bg-light);
  border-radius: 4px;
  height: 24px;
  overflow: hidden;
}

.bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary-light), var(--accent));
  border-radius: 4px;
  transition: width 1s ease;
  width: 0;
}

.bar-value {
  color: var(--primary);
  font-weight: 600;
  text-align: right;
}

.pie-chart {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
}

.pie {
  width: 180px;
  height: 180px;
  border-radius: 50%;
  position: relative;
}

.pie-legend {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
}

.legend-color {
  width: 14px;
  height: 14px;
  border-radius: 3px;
}

/* ===== 感言卡片 ===== */
.testimonial-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.testimonial-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  border-left: 4px solid var(--accent);
  position: relative;
}

.testimonial-card::before {
  content: """;
  position: absolute;
  top: 8px;
  right: 16px;
  font-size: 48px;
  color: var(--border);
  font-family: Georgia, serif;
  line-height: 1;
}

.testimonial-text {
  font-size: 15px;
  color: var(--text-main);
  font-style: italic;
  position: relative;
  z-index: 1;
}

/* ===== 页脚 ===== */
.footer {
  background: var(--primary);
  color: rgba(255, 255, 255, 0.8);
  padding: 40px 24px 24px;
  text-align: center;
}

.footer-content {
  max-width: var(--max-width);
  margin: 0 auto;
}

.footer h3 {
  color: #fff;
  font-size: 20px;
  margin-bottom: 12px;
}

.footer p {
  font-size: 14px;
  margin-bottom: 8px;
}

.footer-links {
  margin: 20px 0;
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
}

.footer-links a:hover {
  color: #fff;
}

.footer-copy {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  padding-top: 20px;
  margin-top: 20px;
  font-size: 13px;
  opacity: 0.7;
}

/* ===== 工具类 ===== */
.text-center { text-align: center; }
.mt-40 { margin-top: 40px; }
.mb-40 { margin-bottom: 40px; }
.bg-light { background: var(--bg-card); }

.badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 600;
}
.badge-primary { background: rgba(0, 102, 204, 0.12); color: var(--primary-light); }
.badge-accent { background: rgba(0, 168, 232, 0.15); color: #0077b6; }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }

  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--primary);
    flex-direction: column;
    padding: 16px;
    gap: 4px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s;
  }

  .nav-menu.open {
    max-height: 600px;
  }

  .nav-menu a {
    display: block;
    padding: 12px 16px;
  }

  .hero-title {
    font-size: 30px;
  }

  .hero-subtitle {
    font-size: 15px;
  }

  .container {
    padding: 40px 20px;
  }

  .section-title h2 {
    font-size: 26px;
  }

  .stat-number {
    font-size: 28px;
  }

  .bar-item {
    grid-template-columns: 120px 1fr 50px;
    font-size: 13px;
  }

  .timeline {
    padding-left: 24px;
  }

  .quote-block {
    padding: 28px 20px;
  }

  .quote-block p {
    font-size: 16px;
  }
}