/* =============================================
   四虎 修车改装 - 主样式文件
   cjwizs.cn | 原创设计
   ============================================= */

/* CSS变量 */
:root {
  --primary: #0a1628;
  --accent: #e85d04;
  --accent2: #1565c0;
  --gold: #f4a820;
  --light: #f5f7fa;
  --white: #ffffff;
  --dark: #0d0d0d;
  --gray: #6b7280;
  --gray-light: #e5e7eb;
  --font-main: 'Microsoft YaHei', 'PingFang SC', 'Helvetica Neue', Arial, sans-serif;
  --shadow: 0 4px 24px rgba(0,0,0,0.12);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.18);
  --radius: 10px;
  --radius-lg: 18px;
  --transition: all 0.3s cubic-bezier(0.4,0,0.2,1);
}

/* Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-main);
  background: var(--light);
  color: var(--dark);
  line-height: 1.7;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { text-decoration: none; color: inherit; transition: var(--transition); }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* =============================================
   通用工具类
   ============================================= */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.section-pad { padding: 80px 0; }
.section-pad-sm { padding: 50px 0; }
.text-center { text-align: center; }
.text-white { color: var(--white); }
.bg-dark { background: var(--primary); }
.bg-light { background: var(--light); }
.bg-white { background: var(--white); }
.flex { display: flex; }
.flex-center { display: flex; align-items: center; justify-content: center; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.hidden { display: none !important; }

/* 标题样式 */
.section-title {
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 14px;
  letter-spacing: -0.5px;
  position: relative;
}
.section-title span { color: var(--accent); }
.section-title::after {
  content: '';
  display: block;
  width: 56px;
  height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--gold));
  border-radius: 2px;
  margin-top: 12px;
}
.section-title.center::after { margin: 12px auto 0; }
.section-subtitle {
  font-size: 1.05rem;
  color: var(--gray);
  margin-bottom: 48px;
  max-width: 600px;
}
.section-subtitle.center { margin-left: auto; margin-right: auto; }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
}
.btn-primary {
  background: var(--accent);
  color: var(--white);
  box-shadow: 0 4px 16px rgba(232,93,4,0.35);
}
.btn-primary:hover { background: #c94e00; transform: translateY(-2px); box-shadow: 0 6px 24px rgba(232,93,4,0.45); }
.btn-secondary {
  background: transparent;
  color: var(--white);
  border: 2px solid rgba(255,255,255,0.6);
}
.btn-secondary:hover { background: rgba(255,255,255,0.1); border-color: var(--white); }
.btn-outline {
  background: transparent;
  color: var(--accent);
  border: 2px solid var(--accent);
}
.btn-outline:hover { background: var(--accent); color: var(--white); }
.btn-dark {
  background: var(--primary);
  color: var(--white);
}
.btn-dark:hover { background: #1a2d4a; transform: translateY(-2px); }

/* =============================================
   顶部公告栏
   ============================================= */
.top-bar {
  background: var(--primary);
  color: rgba(255,255,255,0.85);
  font-size: 0.82rem;
  padding: 7px 0;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}
.top-bar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.top-bar-links a {
  color: rgba(255,255,255,0.7);
  margin-left: 18px;
  font-size: 0.82rem;
}
.top-bar-links a:hover { color: var(--accent); }

/* =============================================
   导航栏
   ============================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(10,22,40,0.97);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 2px 20px rgba(0,0,0,0.25);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}
.nav-logo img {
  width: 48px;
  height: 48px;
  object-fit: contain;
  border-radius: 8px;
}
.nav-logo-text {
  display: flex;
  flex-direction: column;
}
.nav-logo-name {
  font-size: 1.5rem;
  font-weight: 900;
  color: var(--white);
  letter-spacing: 2px;
  line-height: 1;
}
.nav-logo-sub {
  font-size: 0.7rem;
  color: var(--accent);
  letter-spacing: 1px;
  font-weight: 500;
}
.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-menu a {
  color: rgba(255,255,255,0.85);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: 6px;
  transition: var(--transition);
  white-space: nowrap;
}
.nav-menu a:hover, .nav-menu a.active {
  color: var(--white);
  background: rgba(232,93,4,0.2);
  color: var(--accent);
}
.nav-cta {
  display: flex;
  align-items: center;
  gap: 12px;
}
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  cursor: pointer;
}
.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--white);
  border-radius: 2px;
  transition: var(--transition);
}

/* 搜索框 */
.search-bar-wrap {
  background: rgba(255,255,255,0.04);
  border-bottom: 1px solid rgba(255,255,255,0.07);
  padding: 10px 0;
}
.search-bar-inner {
  display: flex;
  align-items: center;
  max-width: 640px;
  margin: 0 auto;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 30px;
  overflow: hidden;
  transition: var(--transition);
}
.search-bar-inner:focus-within {
  border-color: var(--accent);
  background: rgba(255,255,255,0.12);
  box-shadow: 0 0 0 3px rgba(232,93,4,0.15);
}
.search-bar-inner input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  color: var(--white);
  font-size: 0.9rem;
  padding: 9px 18px;
  font-family: var(--font-main);
}
.search-bar-inner input::placeholder { color: rgba(255,255,255,0.4); }
.search-bar-inner button {
  background: var(--accent);
  color: var(--white);
  border: none;
  padding: 9px 20px;
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  font-family: var(--font-main);
}
.search-bar-inner button:hover { background: #c94e00; }

/* =============================================
   面包屑
   ============================================= */
.breadcrumb {
  background: var(--white);
  border-bottom: 1px solid var(--gray-light);
  padding: 12px 0;
  font-size: 0.85rem;
  color: var(--gray);
}
.breadcrumb a { color: var(--accent2); }
.breadcrumb a:hover { color: var(--accent); }
.breadcrumb span { margin: 0 8px; color: var(--gray-light); }

/* =============================================
   Hero Banner
   ============================================= */
.hero-banner {
  position: relative;
  min-height: 580px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: var(--primary);
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  opacity: 0.45;
  transform: scale(1.03);
  transition: transform 8s ease;
}
.hero-banner:hover .hero-bg { transform: scale(1.06); }
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(10,22,40,0.92) 0%, rgba(10,22,40,0.6) 50%, rgba(232,93,4,0.15) 100%);
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 700px;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(232,93,4,0.2);
  border: 1px solid rgba(232,93,4,0.4);
  color: var(--accent);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 5px 14px;
  border-radius: 20px;
  margin-bottom: 20px;
  letter-spacing: 1px;
  text-transform: uppercase;
}
.hero-badge::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse 1.5s infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.4); }
}
.hero-title {
  font-size: 3.2rem;
  font-weight: 900;
  color: var(--white);
  line-height: 1.15;
  margin-bottom: 20px;
  letter-spacing: -1px;
}
.hero-title em {
  font-style: normal;
  color: var(--accent);
  position: relative;
}
.hero-desc {
  font-size: 1.1rem;
  color: rgba(255,255,255,0.8);
  margin-bottom: 36px;
  max-width: 560px;
  line-height: 1.8;
}
.hero-stats {
  display: flex;
  gap: 36px;
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid rgba(255,255,255,0.12);
}
.hero-stat-item { text-align: left; }
.hero-stat-num {
  font-size: 2rem;
  font-weight: 900;
  color: var(--accent);
  line-height: 1;
}
.hero-stat-label {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.6);
  margin-top: 4px;
}
.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; }

/* =============================================
   视频卡片
   ============================================= */
.video-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: var(--primary);
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.08); }
.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.3);
  opacity: 0;
  transition: var(--transition);
}
.video-card:hover .video-play-btn { opacity: 1; }
.play-icon {
  width: 64px;
  height: 64px;
  background: rgba(232,93,4,0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transform: scale(0.85);
  transition: var(--transition);
  box-shadow: 0 4px 20px rgba(232,93,4,0.5);
}
.video-card:hover .play-icon { transform: scale(1); }
.play-icon::after {
  content: '';
  border-style: solid;
  border-width: 10px 0 10px 18px;
  border-color: transparent transparent transparent var(--white);
  margin-left: 4px;
}
.video-duration {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: rgba(0,0,0,0.75);
  color: var(--white);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 4px;
}
.video-tag {
  position: absolute;
  top: 10px;
  left: 10px;
  background: var(--accent);
  color: var(--white);
  font-size: 0.7rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.video-info { padding: 18px; }
.video-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 0.78rem;
  color: var(--gray);
}
.video-meta span { display: flex; align-items: center; gap: 4px; }
.video-stats {
  display: flex;
  gap: 14px;
  margin-top: 10px;
  font-size: 0.78rem;
  color: var(--gray);
}
.video-stats span { display: flex; align-items: center; gap: 4px; }

/* 视频模态框 */
.video-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0,0,0,0.92);
  align-items: center;
  justify-content: center;
}
.video-modal.active { display: flex; }
.video-modal-inner {
  position: relative;
  width: 90%;
  max-width: 900px;
  background: var(--dark);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.video-modal-close {
  position: absolute;
  top: 14px;
  right: 14px;
  z-index: 10;
  width: 36px;
  height: 36px;
  background: rgba(255,255,255,0.15);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  font-size: 1.2rem;
  cursor: pointer;
  transition: var(--transition);
}
.video-modal-close:hover { background: var(--accent); }
.video-modal video, .video-modal iframe {
  width: 100%;
  aspect-ratio: 16/9;
  display: block;
}

/* =============================================
   卡片通用
   ============================================= */
.card {
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: var(--transition);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.card-img { aspect-ratio: 16/9; overflow: hidden; }
.card-img img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.5s; }
.card:hover .card-img img { transform: scale(1.05); }
.card-body { padding: 22px; }
.card-tag {
  display: inline-block;
  background: rgba(232,93,4,0.1);
  color: var(--accent);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 4px;
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
  line-height: 1.4;
}
.card-text { font-size: 0.88rem; color: var(--gray); line-height: 1.6; }

/* =============================================
   专家/团队卡片
   ============================================= */
.expert-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: var(--transition);
  text-align: center;
}
.expert-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.expert-avatar {
  position: relative;
  width: 100%;
  aspect-ratio: 1/1;
  overflow: hidden;
}
.expert-avatar img { width: 100%; height: 100%; object-fit: cover; }
.expert-badge {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent);
  color: var(--white);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 20px;
  white-space: nowrap;
}
.expert-info { padding: 20px; }
.expert-name { font-size: 1.1rem; font-weight: 800; color: var(--primary); margin-bottom: 4px; }
.expert-role { font-size: 0.82rem; color: var(--accent); font-weight: 600; margin-bottom: 10px; }
.expert-desc { font-size: 0.83rem; color: var(--gray); line-height: 1.6; margin-bottom: 14px; }
.expert-social { display: flex; justify-content: center; gap: 10px; }
.expert-social a {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  color: var(--gray);
  transition: var(--transition);
}
.expert-social a:hover { background: var(--accent); color: var(--white); }
.expert-btns { display: flex; gap: 8px; justify-content: center; margin-top: 14px; }
.expert-btns a {
  flex: 1;
  text-align: center;
  padding: 7px 12px;
  border-radius: 6px;
  font-size: 0.78rem;
  font-weight: 600;
  transition: var(--transition);
}
.expert-btns .btn-view {
  background: var(--primary);
  color: var(--white);
}
.expert-btns .btn-view:hover { background: var(--accent2); }
.expert-btns .btn-contact {
  background: var(--light);
  color: var(--primary);
  border: 1px solid var(--gray-light);
}
.expert-btns .btn-contact:hover { background: var(--accent); color: var(--white); border-color: var(--accent); }

/* =============================================
   评价/口碑
   ============================================= */
.review-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 28px;
  transition: var(--transition);
  border-left: 4px solid transparent;
}
.review-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-left-color: var(--accent);
}
.review-stars { color: var(--gold); font-size: 1rem; margin-bottom: 12px; letter-spacing: 2px; }
.review-text { font-size: 0.92rem; color: #444; line-height: 1.7; margin-bottom: 18px; font-style: italic; }
.review-author { display: flex; align-items: center; gap: 12px; }
.review-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--gold));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  font-weight: 800;
  font-size: 1rem;
  flex-shrink: 0;
}
.review-name { font-weight: 700; font-size: 0.9rem; color: var(--primary); }
.review-label { font-size: 0.75rem; color: var(--gray); }

/* =============================================
   FAQ
   ============================================= */
.faq-item {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  margin-bottom: 14px;
  overflow: hidden;
  border: 1px solid var(--gray-light);
  transition: var(--transition);
}
.faq-item.open { border-color: var(--accent); }
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 22px;
  cursor: pointer;
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--primary);
  user-select: none;
  transition: var(--transition);
}
.faq-question:hover { color: var(--accent); }
.faq-icon {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: var(--accent);
  flex-shrink: 0;
  transition: var(--transition);
  font-weight: 300;
}
.faq-item.open .faq-icon { background: var(--accent); color: var(--white); transform: rotate(45deg); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.3s ease;
  padding: 0 22px;
}
.faq-item.open .faq-answer { max-height: 300px; padding: 0 22px 18px; }
.faq-answer p { font-size: 0.9rem; color: var(--gray); line-height: 1.7; }

/* =============================================
   合作品牌Logo墙
   ============================================= */
.partners-section { background: var(--white); padding: 50px 0; }
.partners-grid {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 32px;
  margin-top: 36px;
}
.partner-item {
  background: var(--light);
  border: 1px solid var(--gray-light);
  border-radius: var(--radius);
  padding: 16px 28px;
  min-width: 120px;
  text-align: center;
  font-weight: 800;
  font-size: 1rem;
  color: var(--gray);
  transition: var(--transition);
  letter-spacing: 1px;
}
.partner-item:hover { border-color: var(--accent); color: var(--accent); background: rgba(232,93,4,0.05); transform: translateY(-2px); }

/* =============================================
   社区加入指南
   ============================================= */
.join-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; margin-top: 40px; }
.join-step {
  text-align: center;
  padding: 32px 20px;
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  position: relative;
  transition: var(--transition);
}
.join-step:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.join-step-num {
  width: 52px;
  height: 52px;
  background: linear-gradient(135deg, var(--accent), var(--gold));
  color: var(--white);
  font-size: 1.3rem;
  font-weight: 900;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
}
.join-step-title { font-size: 1rem; font-weight: 700; color: var(--primary); margin-bottom: 8px; }
.join-step-text { font-size: 0.85rem; color: var(--gray); line-height: 1.6; }

/* =============================================
   联系信息
   ============================================= */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.contact-info-block { background: var(--white); border-radius: var(--radius-lg); padding: 36px; box-shadow: var(--shadow); }
.contact-info-block h3 { font-size: 1.2rem; font-weight: 800; color: var(--primary); margin-bottom: 24px; }
.contact-item { display: flex; gap: 14px; margin-bottom: 20px; }
.contact-icon {
  width: 44px;
  height: 44px;
  background: rgba(232,93,4,0.1);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
}
.contact-item-text { font-size: 0.88rem; color: var(--gray); line-height: 1.6; }
.contact-item-text strong { display: block; color: var(--primary); font-weight: 700; margin-bottom: 2px; }
.qr-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 24px; }
.qr-item { text-align: center; }
.qr-item img { width: 120px; height: 120px; margin: 0 auto 8px; border-radius: 8px; border: 2px solid var(--gray-light); }
.qr-item p { font-size: 0.78rem; color: var(--gray); }

/* =============================================
   社交分享
   ============================================= */
.share-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.share-label { font-size: 0.85rem; color: var(--gray); font-weight: 600; }
.share-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
  border: none;
}
.share-wechat { background: #07c160; color: var(--white); }
.share-weibo { background: #e6162d; color: var(--white); }
.share-douyin { background: #010101; color: var(--white); }
.share-bilibili { background: #00a1d6; color: var(--white); }
.share-btn:hover { opacity: 0.85; transform: translateY(-2px); }

/* =============================================
   AI功能区
   ============================================= */
.ai-section { background: linear-gradient(135deg, var(--primary) 0%, #1a2d4a 100%); color: var(--white); }
.ai-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 48px; }
.ai-card {
  background: rgba(255,255,255,0.07);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
}
.ai-card:hover {
  background: rgba(255,255,255,0.12);
  border-color: var(--accent);
  transform: translateY(-4px);
}
.ai-icon {
  width: 64px;
  height: 64px;
  background: linear-gradient(135deg, var(--accent), var(--gold));
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin: 0 auto 18px;
}
.ai-card h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: 10px; }
.ai-card p { font-size: 0.85rem; color: rgba(255,255,255,0.7); line-height: 1.6; }

/* =============================================
   统计数字区
   ============================================= */
.stats-section {
  background: linear-gradient(90deg, var(--accent) 0%, #c94e00 100%);
  padding: 60px 0;
}
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.stat-item { text-align: center; color: var(--white); }
.stat-num { font-size: 2.8rem; font-weight: 900; line-height: 1; margin-bottom: 8px; }
.stat-label { font-size: 0.88rem; opacity: 0.85; }

/* =============================================
   页脚
   ============================================= */
.site-footer {
  background: #060e1a;
  color: rgba(255,255,255,0.7);
  padding: 64px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}
.footer-brand { }
.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.footer-logo img { width: 44px; height: 44px; object-fit: contain; border-radius: 8px; }
.footer-logo-name { font-size: 1.4rem; font-weight: 900; color: var(--white); letter-spacing: 2px; }
.footer-desc { font-size: 0.85rem; line-height: 1.8; margin-bottom: 20px; max-width: 280px; }
.footer-social { display: flex; gap: 10px; }
.footer-social a {
  width: 36px;
  height: 36px;
  background: rgba(255,255,255,0.08);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  color: rgba(255,255,255,0.6);
  transition: var(--transition);
}
.footer-social a:hover { background: var(--accent); color: var(--white); }
.footer-col h4 { font-size: 0.95rem; font-weight: 700; color: var(--white); margin-bottom: 18px; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { font-size: 0.85rem; color: rgba(255,255,255,0.6); transition: var(--transition); }
.footer-col ul li a:hover { color: var(--accent); padding-left: 4px; }
.footer-bottom {
  padding: 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
  flex-wrap: wrap;
  gap: 12px;
}
.footer-bottom a { color: rgba(255,255,255,0.4); }
.footer-bottom a:hover { color: var(--accent); }
.footer-qr { display: flex; gap: 24px; margin-top: 20px; }
.footer-qr-item { text-align: center; }
.footer-qr-item img { width: 90px; height: 90px; border-radius: 8px; margin-bottom: 6px; }
.footer-qr-item p { font-size: 0.72rem; color: rgba(255,255,255,0.5); }

/* =============================================
   页面内部样式
   ============================================= */
.page-hero {
  background: linear-gradient(135deg, var(--primary) 0%, #1a2d4a 100%);
  padding: 64px 0;
  color: var(--white);
  position: relative;
  overflow: hidden;
}
.page-hero::after {
  content: '';
  position: absolute;
  right: -80px;
  top: -80px;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(232,93,4,0.15) 0%, transparent 70%);
  pointer-events: none;
}
.page-hero h1 { font-size: 2.4rem; font-weight: 900; margin-bottom: 12px; }
.page-hero p { font-size: 1rem; color: rgba(255,255,255,0.75); max-width: 560px; }

/* =============================================
   响应式
   ============================================= */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .join-steps { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .hero-title { font-size: 2rem; }
  .section-title { font-size: 1.6rem; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .ai-cards { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .nav-menu { display: none; }
  .hamburger { display: flex; }
  .nav-cta .btn { display: none; }
  .hero-stats { gap: 20px; }
  .hero-stat-num { font-size: 1.5rem; }
  .footer-grid { grid-template-columns: 1fr; }
  .join-steps { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-banner { min-height: 420px; }
  .section-pad { padding: 50px 0; }
  .nav-menu.open {
    display: flex;
    flex-direction: column;
    position: fixed;
    inset: 0;
    top: 68px;
    background: rgba(10,22,40,0.98);
    padding: 30px 20px;
    z-index: 999;
    gap: 8px;
  }
  .nav-menu.open a { font-size: 1.1rem; padding: 14px 20px; }
}

@media (max-width: 480px) {
  .container { padding: 0 14px; }
  .hero-title { font-size: 1.6rem; }
  .hero-btns { flex-direction: column; }
  .btn { width: 100%; justify-content: center; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .stat-num { font-size: 2rem; }
}

/* 懒加载动画 */
.lazy-load { opacity: 0; transform: translateY(20px); transition: opacity 0.6s ease, transform 0.6s ease; }
.lazy-load.loaded { opacity: 1; transform: translateY(0); }

/* 滚动条 */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--light); }
::-webkit-scrollbar-thumb { background: var(--accent); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #c94e00; }

/* 选中颜色 */
::selection { background: rgba(232,93,4,0.2); color: var(--primary); }