/* =============================================
   黄页网站 - style.css
   全局样式 / 导航 / 模块 / 卡片 / 页脚
   ============================================= */

/* ---------- CSS变量 ---------- */
:root {
 -primary: #f5a623;
 -primary-dark: #d4881a;
-primary-light: #ffd280;
 -secondary: #2c3e50;
-secondary-light: #34495e;
 -accent: #e74c3c;
-bg: #f8f6f0;
 -bg-card: #ffffff;
  -bg-dark: #1a1a2e;
  -text: #333333;
  -text-light: #666666;
  -text-muted: #999999;
  -border: #e8e0cc;
  -shadow: 0 4px 20px rgba(245,166,35,0.12);
  -shadow-hover: 0 8px 32px rgba(245,166,35,0.25);
  -radius: 10px;
  -radius-lg: 16px;
  -transition: 0.3s ease;
  -header-h: 68px;
}

/* ---------- 重置 ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: "PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--primary); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }
h1,h2,h3,h4,h5,h6 { line-height: 1.3; font-weight: 700; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* ---------- 容器 ---------- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* =============================================
   HEADER / NAV
   ============================================= */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 2px solid var(--primary-light);
  z-index: 1000;
  box-shadow: 0 2px 16px rgba(245,166,35,0.10);
  transition: box-shadow var(--transition);
}
.site-header.scrolled {
  box-shadow: 0 4px 24px rgba(245,166,35,0.18);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

/* Logo */
.logo a {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--secondary);
}
.logo-svg { width: 42px; height: 42px; border-radius: 8px; }
.logo-text {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-size: 1.25rem;
  letter-spacing: 1px;
}

/* 主导航 */
.main-nav ul {
  display: flex;
  align-items: center;
  gap: 4px;
}
.main-nav ul li a {
  display: block;
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--secondary);
  transition: all var(--transition);
  position: relative;
}
.main-nav ul li a::after {
  content: '';
  position: absolute;
  bottom: 2px; left: 50%; right: 50%;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
  transition: all var(--transition);
}
.main-nav ul li a:hover {
  color: var(--primary);
  background: rgba(245,166,35,0.08);
}
.main-nav ul li a:hover::after {
  left: 16%; right: 16%;
}

/* 汉堡菜单 */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
  border-radius: 6px;
  transition: background var(--transition);
}
.nav-toggle:hover { background: rgba(245,166,35,0.1); }
.nav-toggle span {
  display: block;
  width: 24px; height: 2px;
  background: var(--secondary);
  border-radius: 2px;
  transition: all var(--transition);
}
.nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* =============================================
   HERO BANNER / 轮播
   ============================================= */
.hero-banner {
  position: relative;
  height: 580px;
  margin-top: var(--header-h);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}
.banner-slides {
  position: absolute;
  inset: 0;
}
.banner-slide {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  opacity: 0;
  transition: opacity 1.2s ease;
}
.banner-slide.active { opacity: 1; }
.banner-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(26,26,46,0.72) 0%,
    rgba(44,62,80,0.55) 50%,
    rgba(245,166,35,0.18) 100%
  );
  z-index: 1;
}
.banner-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: #fff;
  padding: 0 20px;
}
.banner-title {
  font-size: clamp(1.6rem, 4vw, 2.8rem);
  font-weight: 900;
  margin-bottom: 16px;
  text-shadow: 0 2px 12px rgba(0,0,0,0.4);
  letter-spacing: 2px;
}
.banner-desc {
  font-size: 1.1rem;
  opacity: 0.92;
  margin-bottom: 32px;
  text-shadow: 0 1px 6px rgba(0,0,0,0.3);
}
.banner-search {
  display: flex;
  max-width: 580px;
  margin: 0 auto 28px;
  border-radius: 50px;
  overflow: hidden;
  box-shadow: 0 6px 30px rgba(0,0,0,0.25);
}
.search-input {
  flex: 1;
  padding: 14px 24px;
  font-size: 1rem;
  border: none;
  outline: none;
  color: var(--text);
  background: #fff;
}
.search-btn {
  padding: 14px 32px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
  border: none;
  cursor: pointer;
  transition: opacity var(--transition);
  white-space: nowrap;
}
.search-btn:hover { opacity: 0.9; }
.banner-stats {
  display: flex;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
}
.banner-stats span {
  font-size: 0.95rem;
  opacity: 0.9;
}
.banner-stats strong {
  color: var(--primary-light);
  font-size: 1.15rem;
  margin-right: 4px;
}
.banner-dots {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 8px;
  z-index: 3;
}
.dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  background: rgba(255,255,255,0.45);
  cursor: pointer;
  transition: all var(--transition);
}
.dot.active {
  background: var(--primary);
  width: 28px;
  border-radius: 5px;
}

/* =============================================
   通用 SECTION 样式
   ============================================= */
.section {
  padding: 72px 0;
}
.section:nth-child(even) {
  background: #fff;
}
.section-header {
  text-align: center;
  margin-bottom: 48px;
}
.section-header.light .section-title,
.section-header.light .section-sub {
  color: #fff;
}
.section-title {
  font-size: clamp(1.4rem, 3vw, 2rem);
  color: var(--secondary);
  margin-bottom: 12px;
  position: relative;
  display: inline-block;
}
.section-title::after {
  content: '';
  display: block;
  width: 56px; height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  border-radius: 2px;
  margin: 10px auto 0;
}
.section-sub {
  color: var(--text-light);
  font-size: 1rem;
  margin-top: 8px;
}

/* =============================================
   行业分类
   ============================================= */
.industry-nav { background: var(--bg); }
.industry-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
}
.industry-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 24px 12px;
  background: #fff;
  border-radius: var(--radius);
  border: 1.5px solid var(--border);
  transition: all var(--transition);
  text-align: center;
  cursor: pointer;
}
.industry-item:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-hover);
  transform: translateY(-4px);
}
.industry-icon {
  font-size: 2rem;
  line-height: 1;
}
.industry-item span {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--secondary);
}
.industry-item em {
  font-style: normal;
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* =============================================
   精选企业卡片
   ============================================= */
.featured-companies { background: #fff; }
.company-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.company-card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1.5px solid var(--border);
  box-shadow: var(--shadow);
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
}
.company-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-6px);
  border-color: var(--primary-light);
}
.card-img-wrap {
  position: relative;
  height: 200px;
  overflow: hidden;
}
.card-img-wrap img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.company-card:hover .card-img-wrap img {
  transform: scale(1.06);
}
.card-badge {
  position: absolute;
  top: 12px; right: 12px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 20px;
  box-shadow: 0 2px 8px rgba(245,166,35,0.4);
}
.card-body {
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.card-title {
  font-size: 1.05rem;
  color: var(--secondary);
  font-weight: 700;
}
.card-cat {
  font-size: 0.85rem;
  color: var(--primary-dark);
  font-weight: 500;
}
.card-desc {
  font-size: 0.88rem;
  color: var(--text-light);
  line-height: 1.65;
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 4;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.card-info {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
  padding: 8px 0;
  border-top: 1px solid var(--border);
}
.card-btn {
  display: block;
  text-align: center;
  padding: 10px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.9rem;
  transition: opacity var(--transition);
  margin-top: 4px;
}
.card-btn:hover { opacity: 0.88; color: #fff; }

/* =============================================
   最新入驻商家
   ============================================= */
.new-merchants { background: var(--bg); }
.merchant-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}
.merchant-item {
  display: flex;
  align-items: center;
  gap: 16px;
  background: #fff;
  border-radius: var(--radius);
  padding: 16px;
  border: 1.5px solid var(--border);
  transition: all var(--transition);
}
.merchant-item:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow);
  transform: translateX(4px);
}
.merchant-item img {
  width: 72px; height: 72px;
  border-radius: 8px;
  object-fit: cover;
  flex-shrink: 0;
}
.merchant-info { flex: 1; min-width: 0; }
.merchant-info h3 {
  font-size: 0.98rem;
  font-weight: 700;
  margin-bottom: 4px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.merchant-info h3 a:hover { color: var(--primary); }
.merchant-info p {
  font-size: 0.82rem;
  color: var(--text-light);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.merchant-tag {
  display: inline-block;
  margin-top: 6px;
  background: rgba(245,166,35,0.12);
  color: var(--primary-dark);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
}
.merchant-contact {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 8px;
  flex-shrink: 0;
}
.merchant-contact span {
  font-size: 0.82rem;
  color: var(--text-muted);
  white-space: nowrap;
}
.mini-btn {
  padding: 5px 14px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border-radius: 6px;
  font-size: 0.82rem;
  font-weight: 600;
  transition: opacity var(--transition);
}
.mini-btn:hover { opacity: 0.85; color: #fff; }

/* =============================================
   文章模块
   ============================================= */
.articles-section { background: #fff; }
.articles-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}
.article-card {
  display: flex;
  gap: 20px;
  background: var(--bg);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1.5px solid var(--border);
  transition: all var(--transition);
  padding: 0;
}
.article-card:hover {
  box-shadow: var(--shadow-hover);
  border-color: var(--primary-light);
  transform: translateY(-3px);
}
.article-img {
  width: 180px;
  flex-shrink: 0;
  overflow: hidden;
}
.article-img img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.article-card:hover .article-img img { transform: scale(1.06); }
.article-content {
  padding: 20px 20px 20px 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}
.article-tag {
  display: inline-block;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 4px;
  width: fit-content;
}
.article-content h3 {
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--secondary);
  line-height: 1.4;
}
.article-content h3 a:hover { color: var(--primary); }
.article-content p {
  font-size: 0.85rem;
  color: var(--text-light);
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 4;
  -webkit-box-orient: vertical;
  overflow: hidden;
  flex: 1;
}
.article-meta {
  display: flex;
  gap: 16px;
  font-size: 0.78rem;
  color: var(--text-muted);
  padding-top: 8px;
  border-top: 1px solid var(--border);
}

/* =============================================
   APP下载
   ============================================= */
.app-download {
  background: linear-gradient(135deg, var(--secondary) 0%, var(--secondary-light) 50%, #16213e 100%);
  position: relative;
  overflow: hidden;
}
.app-download::before {
  content: '';
  position: absolute;
  top: -60px; right: -60px;
  width: 300px; height: 300px;
  background: radial-gradient(circle, rgba(245,166,35,0.18) 0%, transparent 70%);
  border-radius: 50%;
}
.app-download::after {
  content: '';
  position: absolute;
  bottom: -80px; left: -40px;
  width: 250px; height: 250px;
  background: radial-gradient(circle, rgba(245,166,35,0.12) 0%, transparent 70%);
  border-radius: 50%;
}
.app-download-inner {
  display: flex;
  align-items: center;
  gap: 60px;
  position: relative;
  z-index: 1;
}
.app-text { flex: 1; color: #fff; }
.app-text h2 {
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  margin-bottom: 8px;
  color: #fff;
}
.app-slogan {
  font-size: 1.05rem;
  color: var(--primary-light);
  margin-bottom: 24px;
}
.app-features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 32px;
}
.app-features li {
  font-size: 0.92rem;
  color: rgba(255,255,255,0.88);
}
.app-btns {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}
.app-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 13px 28px;
  border-radius: 10px;
  font-size: 1rem;
  font-weight: 700;
  transition: all var(--transition);
}
.app-btn svg { width: 22px; height: 22px; }
.app-btn.android {
  background: linear-gradient(135deg, #3ddc84, #2ba866);
  color: #fff;
}
.app-btn.ios {
  background: linear-gradient(135deg, #555, #222);
  color: #fff;
}
.app-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0,0,0,0.3); color: #fff; }
.app-qr-tip {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.6);
}
.app-mockup {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.app-mockup > img {
  width: 220px;
  border-radius: 20px;
  box-shadow: 0 16px 48px rgba(0,0,0,0.4);
}
.app-qr {
  text-align: center;
}
.app-qr img {
  width: 100px; height: 100px;
  border-radius: 8px;
  border: 3px solid rgba(255,255,255,0.2);
  margin: 0 auto 6px;
}
.app-qr p {
  font-size: 0.78rem;
  color: rgba(255,255,255,0.6);
}

/* =============================================
   城市黄页
   ============================================= */
.city-section { background: var(--bg); }
.city-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 24px;
  justify-content: center;
}
.city-tab {
  padding: 9px 22px;
  border-radius: 24px;
  border: 1.5px solid var(--border);
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-light);
  background: #fff;
  transition: all var(--transition);
}
.city-tab:hover,
.city-tab.active {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(245,166,35,0.3);
}
.city-panel { display: none; }
.city-panel.active { display: block; }
.city-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 12px;
}
.city-link {
  display: block;
  text-align: center;
  padding: 12px 8px;
  background: #fff;
  border-radius: 8px;
  border: 1.5px solid var(--border);
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--secondary);
  transition: all var(--transition);
}
.city-link:hover {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(245,166,35,0.25);
}

/* =============================================
   数据统计
   ============================================= */
.stats-section {
  position: relative;
  padding: 80px 0;
  overflow: hidden;
}
.stats-bg {
  position: absolute;
  inset: 0;
}
.stats-bg-img {
  width: 100%; height: 100%;
  object-fit: cover;
}
.stats-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(26,26,46,0.88), rgba(44,62,80,0.82));
}
.stats-content {
  position: relative;
  z-index: 1;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 24px;
}
.stat-item {
  text-align: center;
  color: #fff;
  padding: 28px 16px;
  background: rgba(255,255,255,0.06);
  border-radius: var(--radius);
  border: 1px solid rgba(245,166,35,0.2);
  backdrop-filter: blur(4px);
  transition: all var(--transition);
}
.stat-item:hover {
  background: rgba(245,166,35,0.12);
  border-color: rgba(245,166,35,0.4);
  transform: translateY(-4px);
}
.stat-num {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 900;
  color: var(--primary-light);
  line-height: 1;
  margin-bottom: 10px;
}
.stat-label {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.8);
}

/* =============================================
   合作伙伴
   ============================================= */
.partners-section { background: #fff; }
.partners-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 20px;
}
.partner-item {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1.5px solid var(--border);
  transition: all var(--transition);
  aspect-ratio: 3/2;
}
.partner-item img {
  width: 100%; height: 100%;
  object-fit: cover;
  filter: grayscale(30%);
  transition: all var(--transition);
}
.partner-item:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow);
}
.partner-item:hover img {
  filter: grayscale(0%);
  transform: scale(1.04);
}

/* =============================================
   FOOTER
   ============================================= */
.site-footer {
  background: var(--bg-dark);
  color: rgba(255,255,255,0.8);
}
.footer-top { padding: 60px 0 40px; }
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: 40px;
}
.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.footer-logo span {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--primary);
}
.footer-about p {
  font-size: 0.88rem;
  line-height: 1.8;
  color: rgba(255,255,255,0.65);
  margin-bottom: 16px;
}
.footer-contact p {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.6);
  margin-bottom: 6px;
}
.footer-col h4 {
  font-size: 1rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 18px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--primary);
  display: inline-block;
}
.footer-col ul li {
  margin-bottom: 9px;
}
.footer-col ul li a {
  font-size: 0.88rem;
  color: rgba(255,255,255,0.6);
  transition: color var(--transition);
}
.footer-col ul li a:hover { color: var(--primary); }

/* 友情链接 */
.footer-links-wrap {
  background: rgba(255,255,255,0.04);
  border-top: 1px solid rgba(255,255,255,0.08);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  padding: 16px 0;
}
.footer-flink {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  flex-wrap: wrap;
}
.flink-title {
  font-size: 0.88rem;
  color: var(--primary);
  font-weight: 700;
  white-space: nowrap;
  padding-top: 2px;
}
.footer-flink ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
}
.footer-flink ul li a,
.footer-flink a {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.55);
  transition: color var(--transition);
}
.footer-flink ul li a:hover,
.footer-flink a:hover { color: var(--primary); }

/* 版权 */
.footer-bottom {
  padding: 20px 0;
}
.footer-bottom-inner {
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.copyright {
  font-size: 0.88rem;
  color: rgba(255,255,255,0.55);
}
.copyright a:hover { color: var(--primary); }
.beian {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}
.beian a { color: rgba(255,255,255,0.45); }
.beian a:hover { color: var(--primary); }
.footer-disclaimer {
  font-size: 0.78rem;
  color: rgba(255,255,255,0.3);
}

/* =============================================
   回到顶部
   ============================================= */
.back-to-top {
  position: fixed;
  bottom: 32px; right: 28px;
  width: 44px; height: 44px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border-radius: 50%;
  font-size: 1rem;
  box-shadow: 0 4px 16px rgba(245,166,35,0.4);
  opacity: 0;
  pointer-events: none;
  transition: all var(--transition);
  z-index: 999;
  display: flex;
  align-items: center;
  justify-content: center;
}
.back-to-top.show {
  opacity: 1;
  pointer-events: auto;
}
.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(245,166,35,0.5);
}

/* =============================================
   响应式
   ============================================= */
@media (max-width: 1100px) {
  .industry-grid { grid-template-columns: repeat(4, 1fr); }
  .company-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(3, 1fr); }
  .partners-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr 1fr; gap: 28px; }
  .footer-about { grid-column: 1 / -1; }
}
@media (max-width: 860px) {
  .hero-banner { height: 460px; }
  .industry-grid { grid-template-columns: repeat(3, 1fr); }
  .articles-grid { grid-template-columns: 1fr; }
  .merchant-list { grid-template-columns: 1fr; }
  .city-grid { grid-template-columns: repeat(4, 1fr); }
  .app-download-inner { flex-direction: column; gap: 32px; }
  .app-mockup { flex-direction: row; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .partners-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  :root { --header-h: 58px; }
  .main-nav {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0; right: 0;
    background: #fff;
    border-bottom: 2px solid var(--primary-light);
    padding: 12px 0;
    box-shadow: 0 8px 24px rgba(0,0,0,0.1);
  }
  .main-nav.open { display: block; }
  .main-nav ul { flex-direction: column; gap: 0; }
  .main-nav ul li a { padding: 12px 24px; border-radius: 0; }
  .nav-toggle { display: flex; }
  .hero-banner { height: 380px; }
  .banner-search { flex-direction: column; border-radius: var(--radius); }
  .search-input, .search-btn { border-radius: 0; }
  .search-input { border-radius: var(--radius) var(--radius) 0 0; }
  .search-btn { border-radius: 0 0 var(--radius) var(--radius); }
  .banner-stats { gap: 16px; }
  .industry-grid { grid-template-columns: repeat(3, 1fr); }
  .company-grid { grid-template-columns: 1fr; }
  .article-card { flex-direction: column; }
  .article-img { width: 100%; height: 180px; }
  .article-content { padding: 16px; }
  .city-grid { grid-template-columns: repeat(3, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .partners-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .app-features { grid-template-columns: 1fr; }
  .app-mockup { flex-direction: column; }
  .section { padding: 48px 0; }
}
@media (max-width: 400px) {
  .industry-grid { grid-template-columns: repeat(2, 1fr); }
  .city-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: 1fr 1fr; }
}