/* ========== 基础变量 ========== */
:root {
  --primary: #154897;
  --primary-dark: #0f3a7a;
  --primary-light: #e0eaf7;
  --accent: #f59e0b;
  --text: #1f2937;
  --text-light: #6b7280;
  --text-muted: #9ca3af;
  --bg: #ffffff;
  --bg-light: #f9fafb;
  --bg-alt: #f3f4f6;
  --border: #e5e7eb;
  --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.1), 0 2px 4px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
  --radius: 8px;
  --radius-lg: 12px;
  --transition: 0.2s ease;
  --max-width: 1200px;
}

/* ========== 全局 ========== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 15px;
}

a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--primary-dark); }

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

ul { list-style: none; }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ========== 导航栏 ========== */
.navbar {
  position: sticky;
  top: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  backdrop-filter: blur(8px);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.nav-logo {
  font-size: 18px;
  font-weight: 600;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-logo .logo-icon {
  width: 32px;
  height: 32px;
  background: var(--primary);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 14px;
}

.nav-logo .logo-img {
  height: 56px;
  width: auto;
  display: block;
}

.footer .nav-logo .logo-img {
  height: 48px;
  width: auto;
  display: block;
}

.nav-links { display: flex; gap: 32px; }

.nav-links a {
  color: var(--text-light);
  font-size: 14px;
  font-weight: 500;
  padding: 4px 0;
  position: relative;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary);
}

.nav-links a.active::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--primary);
  border-radius: 1px;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle svg { width: 24px; height: 24px; stroke: var(--text); }

/* ========== Hero ========== */
.hero {
  padding: 80px 0;
  background: linear-gradient(135deg, var(--primary-light) 0%, var(--bg) 60%);
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.hero-title {
  font-size: 36px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 16px;
  color: var(--text);
}

.hero-title span { color: var(--primary); }

.hero-desc {
  font-size: 16px;
  color: var(--text-light);
  margin-bottom: 32px;
  line-height: 1.8;
}

.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }

.hero-visual {
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-slider {
  position: relative;
  width: 100%;
  max-width: 520px;
}

.hero-visual .hero-product-img {
  width: 100%;
  max-width: 520px;
  height: auto;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  object-fit: cover;
  position: absolute;
  top: 0;
  left: 0;
  opacity: 0;
  transition: opacity 0.6s ease-in-out;
}

.hero-visual .hero-product-img.active {
  position: relative;
  opacity: 1;
}

.hero-slider-dots {
  position: absolute;
  bottom: 16px;
  left: 0;
  right: 0;
  display: flex;
  justify-content: center;
  gap: 8px;
  z-index: 10;
}

.slider-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.5);
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

.slider-dot.active {
  background: var(--primary);
  transform: scale(1.3);
}

.hero-visual .hero-placeholder {
  width: 100%;
  max-width: 480px;
  aspect-ratio: 4/3;
  background: var(--bg-alt);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 14px;
}

/* ========== 按钮 ========== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 24px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.btn-primary:hover {
  background: var(--primary-dark);
  border-color: var(--primary-dark);
}

.btn-outline {
  background: transparent;
  color: var(--primary);
  border-color: var(--primary);
}

.btn-outline:hover {
  background: var(--primary-light);
}

.btn-sm {
  padding: 6px 16px;
  font-size: 13px;
}

.btn-download {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

.btn-download:hover {
  background: #d97706;
}

/* ========== 通用板块 ========== */
.section {
  padding: 64px 0;
}

.section-alt { background: var(--bg-light); }

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

.section-header h2 {
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 12px;
}

.section-header p {
  font-size: 15px;
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
}

/* ========== 特色卡片 ========== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: all var(--transition);
}

.feature-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.feature-icon {
  width: 40px;
  height: 40px;
  border-radius: 8px;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.feature-icon svg { width: 20px; height: 20px; stroke: var(--primary); fill: none; }

.feature-card h3 { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.feature-card p { font-size: 13px; color: var(--text-light); line-height: 1.7; }

/* ========== 应用领域 ========== */
.section-app {
  background: linear-gradient(180deg, #eaf0fa 0%, #f5f8fd 100%);
}

.app-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.app-card {
  background: var(--bg);
  border-radius: var(--radius-lg);
  padding: 40px 24px;
  text-align: center;
  position: relative;
  overflow: hidden;
  border: 1px solid var(--border);
  transition: all var(--transition);
}

.app-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  bottom: 16px;
  width: 4px;
  background: var(--primary);
  border-radius: 0 4px 4px 0;
}

.app-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.app-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.app-icon svg {
  width: 44px;
  height: 44px;
  stroke: var(--primary);
  fill: none;
}

.app-card h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 8px;
}

.app-card p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.6;
}

.app-grid.news-style {
  grid-template-columns: repeat(2, 1fr);
}

.app-grid.news-style .app-card {
  display: flex;
  padding: 20px;
  text-align: left;
  gap: 16px;
  border: 1px solid var(--border);
  background: var(--bg);
  border-radius: var(--radius-lg);
}

.app-grid.news-style .app-card::before { display: none; }

.app-grid.news-style .app-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.app-grid.news-style .app-thumb {
  flex-shrink: 0;
  width: 120px;
  height: 90px;
  background: var(--bg-alt);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.app-grid.news-style .app-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.app-grid.news-style .app-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.app-grid.news-style .app-content h3 {
  font-size: 17px;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 8px;
}

.app-grid.news-style .app-content p {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

@media (max-width: 768px) {
  .app-grid.news-style { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .app-grid.news-style .app-card { flex-direction: column; }
  .app-grid.news-style .app-thumb { width: 100%; height: 160px; }
}

/* ========== 产品布局：顶部筛选栏 + 产品网格 ========== */
.products-filter-bar {
  margin-bottom: 32px;
  border-bottom: 2px solid var(--border);
  padding-bottom: 16px;
}

.filter-tabs {
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
  list-style: none;
  position: relative;
}

.filter-tabs li {
  position: relative;
}

.filter-tab {
  min-width: 120px;
  height: 42px;
  padding: 0 20px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-light);
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  box-sizing: border-box;
}

.filter-tab:hover {
  background: var(--primary-light);
  color: var(--primary);
  border-color: var(--primary);
}

.filter-tab.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.filter-tab .caret {
  font-size: 12px;
  transition: transform var(--transition);
}

.has-submenu:hover .filter-tab .caret {
  transform: rotate(180deg);
}

/* ========== 产品选型器 ========== */
.product-selector {
  margin-bottom: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-light);
  padding: 14px 20px;
}

.selector-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.selector-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-light);
  letter-spacing: 0.5px;
}

.selector-reset {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 2px 10px;
  font-size: 12px;
  color: var(--text-light);
  cursor: pointer;
  transition: all var(--transition);
}

.selector-reset:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.selector-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 7px 0;
}

.selector-row + .selector-row {
  border-top: 1px dashed var(--border);
}

.selector-label {
  font-size: 12px;
  font-weight: 500;
  color: var(--text-muted);
  min-width: 56px;
  line-height: 26px;
  flex-shrink: 0;
}

.selector-options {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.spec-btn {
  padding: 3px 12px;
  height: 26px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-light);
  font-size: 12px;
  line-height: 1;
  cursor: pointer;
  transition: all var(--transition);
}

.spec-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--primary-light);
}

.spec-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

/* 产品选型器内的分类按钮：沿用 filter-tab 视觉但适配选型行密度 */
.product-selector .filter-tab {
  min-width: 0;
  height: 26px;
  padding: 0 12px;
  font-size: 12px;
  border-radius: 6px;
}

/* 下拉子菜单 */
.filter-dropdown {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  margin-top: 8px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: var(--shadow-lg);
  min-width: 140px;
  padding: 8px 0;
  list-style: none;
  opacity: 0;
  visibility: hidden;
  transform: translateX(-50%) translateY(-8px);
  transition: all var(--transition);
  z-index: 100;
}

.has-submenu:hover .filter-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.filter-sub-tab {
  width: 100%;
  padding: 10px 20px;
  background: transparent;
  border: none;
  color: var(--text-light);
  font-size: 14px;
  text-align: center;
  cursor: pointer;
  transition: all var(--transition);
}

.filter-sub-tab:hover {
  background: var(--primary-light);
  color: var(--primary);
}

.filter-sub-tab.active {
  background: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

.products-main {
  min-width: 0;
}

.products-empty {
  text-align: center;
  padding: 48px 24px;
  background: var(--bg-light);
  border-radius: var(--radius-lg);
  border: 1px dashed var(--border);
  color: var(--text-light);
  font-size: 14px;
}

/* ========== 产品网格 ========== */
.products-filter {
  display: flex;
  gap: 8px;
  margin-bottom: 32px;
  justify-content: center;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 8px 20px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text-light);
  font-size: 14px;
  cursor: pointer;
  transition: all var(--transition);
}

.filter-btn:hover,
.filter-btn.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

/* ========== 产品分页（每页5行） ========== */
.products-pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 32px;
}

.products-pagination .page-btn {
  min-width: 36px;
  height: 36px;
  padding: 0 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
  font-family: inherit;
  cursor: pointer;
  transition: border-color var(--transition), color var(--transition), background var(--transition);
}

.products-pagination .page-btn:hover:not(:disabled):not(.active) {
  border-color: var(--primary);
  color: var(--primary);
}

.products-pagination .page-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
  cursor: default;
}

.products-pagination .page-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.products-pagination .page-ellipsis {
  color: var(--text-muted);
  padding: 0 2px;
  font-size: 14px;
}

.products-pagination .page-info {
  font-size: 13px;
  color: var(--text-light);
  margin-left: 10px;
}

.product-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
  cursor: pointer;
}

.product-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.product-thumb {
  aspect-ratio: 4/3;
  background: var(--bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 13px;
  position: relative;
  overflow: hidden;
}

.product-thumb .tag {
  position: absolute;
  top: 12px;
  left: 12px;
  padding: 4px 10px;
  background: var(--primary);
  color: white;
  border-radius: 4px;
  font-size: 11px;
  font-weight: 500;
}

.product-info { padding: 16px; }
.product-info h3 { font-size: 15px; font-weight: 600; margin-bottom: 6px; }
.product-info p { font-size: 13px; color: var(--text-light); margin-bottom: 12px; }
.product-info .product-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.product-info .product-price {
  font-size: 16px;
  font-weight: 600;
  color: var(--primary);
}

/* ========== 下载页面 ========== */
.downloads-categories {
  display: flex;
  gap: 8px;
  margin-bottom: 32px;
  justify-content: center;
  flex-wrap: wrap;
}

.dl-filter-btn {
  padding: 10px 28px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text-light);
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.dl-filter-btn:hover,
.dl-filter-btn.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

/* 下载页面产品手册下拉菜单 */
.dl-has-submenu {
  position: relative;
}

.dl-has-submenu .dl-filter-btn .caret {
  font-size: 11px;
  transition: transform var(--transition);
}

.dl-has-submenu .dl-filter-btn.has-open .caret {
  transform: rotate(180deg);
}

.dl-dropdown {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  margin-top: 8px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: var(--shadow-lg);
  min-width: 140px;
  padding: 8px 0;
  list-style: none;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  z-index: 100;
}

.dl-dropdown.open {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.dl-sub-btn {
  width: 100%;
  padding: 10px 20px;
  background: transparent;
  border: none;
  color: var(--text-light);
  font-size: 14px;
  text-align: center;
  cursor: pointer;
  transition: all var(--transition);
}

.dl-sub-btn:hover {
  background: var(--primary-light);
  color: var(--primary);
}

.dl-sub-btn.active {
  background: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

.dl-list {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg);
}

.dl-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 9px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  transition: all var(--transition);
}

.dl-card:last-child {
  border-bottom: none;
}

.dl-card:hover {
  background: var(--bg-light);
}

.dl-info {
  display: flex;
  align-items: center;
  gap: 16px;
  min-width: 0;
}

.dl-info .dl-icon {
  width: 32px;
  height: 32px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  font-weight: 600;
  color: white;
  flex-shrink: 0;
}

.dl-info .dl-icon.pdf { background: #ef4444; }
.dl-info .dl-icon.doc { background: #3b82f6; }
.dl-info .dl-icon.xls { background: #22c55e; }
.dl-info .dl-icon.zip { background: #f59e0b; }
.dl-info .dl-icon.img { background: #8b5cf6; }
.dl-info .dl-icon.exe { background: #06b6d4; }

.dl-info h4 {
  font-size: 15px;
  font-weight: 500;
  line-height: 1.5;
  color: var(--text);
  margin: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.dl-actions {
  display: flex;
  align-items: center;
  gap: 24px;
  flex-shrink: 0;
}

.dl-size {
  font-size: 14px;
  color: var(--text-muted);
  min-width: 80px;
  text-align: right;
}

.dl-actions .btn-download {
  font-size: 14px;
  padding: 5px 16px;
}

/* ========== 微信侧边栏 ========== */
.contact-sidebar {
  position: fixed;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  z-index: 999;
}

.contact-sidebar-item {
  position: relative;
  width: 54px;
  height: 54px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition);
  margin-bottom: 2px;
}

.contact-sidebar-item.wechat {
  background: #07c160;
  border-radius: 8px 0 0 8px;
}

.contact-sidebar-item:hover {
  width: 58px;
}

.contact-sidebar-item svg {
  width: 26px;
  height: 26px;
  fill: white;
}

.contact-sidebar-item .sidebar-label {
  position: absolute;
  right: 54px;
  top: 50%;
  transform: translateY(-50%);
  white-space: nowrap;
  background: inherit;
  color: white;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 13px;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
}

.contact-sidebar-item:hover .sidebar-label {
  opacity: 1;
}

.contact-sidebar-item .sidebar-popup {
  position: absolute;
  right: 54px;
  top: 50%;
  transform: translateY(-50%);
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 16px;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
  min-width: 160px;
  text-align: center;
}

.contact-sidebar-item:hover .sidebar-popup {
  opacity: 1;
  pointer-events: auto;
}

.sidebar-popup h5 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text);
}

.sidebar-popup p {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.6;
}

.sidebar-popup .qr-placeholder {
  width: 140px;
  height: 140px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 12px;
  margin: 8px auto 0;
  overflow: hidden;
  padding: 0;
}

.sidebar-popup .qr-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

/* ========== 统计数字 ========== */
.stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  padding: 48px 0;
}

.stat-item {
  text-align: center;
}

.stat-item .stat-num {
  font-size: 32px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
}

.stat-item .stat-label {
  font-size: 13px;
  color: var(--text-light);
}

/* ========== 页面标题 ========== */
.page-banner {
  padding: 48px 0;
  background: linear-gradient(135deg, var(--primary-light) 0%, var(--bg) 60%);
  text-align: center;
}

.page-banner h1 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 12px;
}

.page-banner p {
  font-size: 15px;
  color: var(--text-light);
  max-width: 500px;
  margin: 0 auto;
}

/* ========== 联系表单 ========== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: stretch;
}

.contact-col {
  display: flex;
  flex-direction: column;
}

.contact-col .contact-map-card,
.contact-col .contact-info-card {
  flex: 1;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text);
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 14px;
  color: var(--text);
  background: var(--bg);
  transition: border-color var(--transition);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.form-group textarea { resize: vertical; min-height: 120px; }

.contact-info-card {
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.contact-info-item {
  display: flex;
  gap: 12px;
  margin-bottom: 24px;
}

.contact-info-item:last-child { margin-bottom: 0; }

/* 联系方式板块顶部的公司名称 */
.contact-company-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  line-height: 1.5;
  margin: 0 0 20px 0;
  padding: 0;
}

.contact-info-item .ci-icon {
  width: 40px;
  height: 40px;
  border-radius: 8px;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.contact-info-item .ci-icon svg { width: 18px; height: 18px; stroke: var(--primary); fill: none; }
.contact-info-item h4 { font-size: 14px; font-weight: 600; margin-bottom: 4px; }
.contact-info-item p { font-size: 13px; color: var(--text-light); }

.contact-map-card {
  background: var(--bg-light);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 0;
  overflow: hidden;
  display: flex;
  align-items: stretch;
}

.contact-map-card img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

/* ========== 关于页面 ========== */
.about-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

.about-text h3 { font-size: 18px; font-weight: 600; margin-bottom: 12px; }
.about-text p { font-size: 14px; color: var(--text-light); line-height: 1.8; margin-bottom: 16px; text-indent: 2em; }

.about-image-placeholder {
  aspect-ratio: 4/3;
  background: var(--bg-alt);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 14px;
}

.about-image {
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  overflow: hidden;
  display: flex;
  align-items: stretch;
  /* 高度在桌面端由 JS 根据 about-text 实际高度动态设置 */
}

@media (max-width: 768px) {
  .about-image {
    aspect-ratio: 4/3;
  }
}

.about-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.timeline {
  position: relative;
  padding: 32px 0;
}

.timeline-item {
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 24px;
  margin-bottom: 24px;
}

.timeline-year {
  font-size: 16px;
  font-weight: 700;
  color: var(--primary);
  text-align: right;
}

.timeline-content {
  padding-left: 24px;
  border-left: 2px solid var(--primary-light);
}

.timeline-content h4 { font-size: 14px; font-weight: 600; margin-bottom: 4px; }
.timeline-content p { font-size: 13px; color: var(--text-light); }

/* ========== Footer ========== */
.footer {
  background: var(--text);
  color: white;
  padding: 48px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1.2fr;
  gap: 24px;
  margin-bottom: 32px;
}

.footer-brand p { font-size: 13px; color: #9ca3af; line-height: 1.7; margin-top: 12px; }

.footer h4 { font-size: 14px; font-weight: 600; margin-bottom: 16px; }

.footer ul li { margin-bottom: 8px; }
.footer ul li a { font-size: 13px; color: #9ca3af; }
.footer ul li a:hover { color: white; }

.footer-qr {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  padding-top: 0;
}

.footer-qr-img {
  width: 120px;
  height: 120px;
  object-fit: contain;
  border-radius: 8px;
  background: white;
  padding: 6px;
  margin-bottom: 8px;
}

.footer-qr p {
  font-size: 12px;
  color: #9ca3af;
  text-align: center;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 24px;
  text-align: center;
  font-size: 12px;
  color: #9ca3af;
}

/* ========== 新闻弹窗 ========== */
.news-modal {
  max-width: 800px;
}

.news-modal .modal-header {
  justify-content: flex-end;
  margin-bottom: 0;
}

.news-modal-image {
  width: 100%;
  margin-bottom: 24px;
  border-radius: var(--radius);
  overflow: hidden;
}

.news-modal-image img {
  width: 100%;
  height: auto;
  display: block;
}

#newsModalSubtitle {
  text-align: center;
}

#newsModalContent p {
  margin-bottom: 16px;
  text-indent: 2em;
}

.news-modal-views {
  text-align: right;
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 24px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

/* ========== 弹窗 ========== */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0,0,0,0.5);
  z-index: 2000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.modal-overlay.active { display: flex; }

.modal {
  background: var(--bg);
  border-radius: var(--radius-lg);
  max-width: 640px;
  width: 100%;
  max-height: 80vh;
  overflow-y: auto;
  padding: 32px;
}

/* 放大弹窗（0.5倍，用于 TPC4013Ei 等带参数图的产品） */
.modal.modal-lg {
  max-width: 960px;
  max-height: 96vh;
  padding: 40px;
  /* 宽度由内容（参数图）自适应，使弹框宽度与图片宽度一致 */
  width: fit-content;
  min-width: 320px;
}

/* 满屏弹窗（首页「预览参数」系列选型手册查看，保证参数文字清晰） */
.modal.modal-full {
  max-width: none;
  width: 100%;
  max-height: none;
  height: 100%;
  padding: 24px 32px;
}

/* 满屏时主图限高，避免 16:9 撑爆首屏，参数图紧随其后 */
.modal.modal-full .modal-thumb {
  aspect-ratio: auto;
  height: 30vh;
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}

.modal-header h3 { font-size: 18px; font-weight: 600; }

.modal-close {
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-light);
}

.modal-close svg { width: 20px; height: 20px; stroke: currentColor; fill: none; }

.modal-body p { font-size: 14px; color: var(--text-light); line-height: 1.8; margin-bottom: 16px; }

.modal-thumb {
  aspect-ratio: 16/9;
  background: var(--bg-alt);
  border-radius: var(--radius);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 13px;
}

/* ========== 响应式 ========== */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 80px;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    padding: 16px 24px;
    gap: 16px;
  }
  .nav-toggle { display: block; }

  .hero .container { grid-template-columns: 1fr; }
  .hero-visual { order: -1; }
  .hero-title { font-size: 28px; }
  .hero { padding: 48px 0; }

  .features-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .app-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-row { grid-template-columns: repeat(2, 1fr); }

  .dl-card {
    padding: 8px 16px;
    gap: 16px;
  }

  .dl-info { gap: 12px; }

  .dl-info .dl-icon {
    width: 30px;
    height: 30px;
    font-size: 10px;
  }

  .dl-info h4 { font-size: 14px; }

  .dl-actions { gap: 16px; }

  .dl-size {
    font-size: 13px;
    min-width: 70px;
  }

  .dl-actions .btn-download {
    padding: 5px 14px;
    font-size: 13px;
  }

  .about-content { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }

  .filter-tabs {
    flex-wrap: wrap;
    gap: 6px;
  }

  .filter-tab {
    min-width: auto;
    padding: 8px 16px;
    font-size: 13px;
  }

  .product-selector { padding: 12px 14px; }

  .selector-label { min-width: 48px; }

  .filter-dropdown {
    position: static;
    transform: none;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    border: none;
    padding: 0 0 0 20px;
    margin-top: 0;
  }

  .has-submenu:hover .filter-dropdown {
    transform: none;
  }

  .contact-sidebar {
    display: none;
  }

  .dl-subcategories {
    flex-wrap: wrap;
  }
}

@media (max-width: 480px) {
  .products-grid { grid-template-columns: 1fr; }
  .app-grid { grid-template-columns: 1fr; }

  .selector-row { flex-direction: column; gap: 6px; }

  .selector-label { line-height: 1.5; }

  .selector-options { gap: 6px; }

  .spec-btn { padding: 4px 10px; }

  .dl-card {
    padding: 7px 14px;
    gap: 12px;
  }

  .dl-info h4 {
    white-space: normal;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
  }

  .dl-size {
    min-width: auto;
  }

  .dl-actions .btn-download {
    padding: 4px 12px;
  }
}

/* ========== 全站图片版权保护（禁复制/另存/拖拽，触屏禁长按菜单） ========== */
img {
  -webkit-user-drag: none;
  user-drag: none;
  user-select: none;
  -webkit-user-select: none;
  -moz-user-select: none;
  -webkit-touch-callout: none;
}

/* 打印保护：打印/另存为PDF时页面置空，仅输出版权提示 */
@media print {
  body * {
    visibility: hidden !important;
  }
  body::after {
    content: '内容受版权保护，禁止打印';
    visibility: visible;
    position: fixed;
    top: 45%;
    left: 0;
    width: 100%;
    text-align: center;
    font-size: 26px;
    font-weight: 600;
    color: #000;
    background: #fff;
    z-index: 99999;
  }
}

/* ========== 全屏选型手册查看器（首页「预览参数」） ========== */
.pdf-viewer {
  position: fixed;
  inset: 0;
  z-index: 3000;
  background: var(--bg);
  display: none;
}

.pdf-viewer.active { display: block; }

.pdf-viewer-bar {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 2;
}

.pdf-viewer-bar span {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

.pdf-viewer-close {
  background: var(--bg-alt);
  border: none;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  cursor: pointer;
  font-size: 15px;
  line-height: 1;
  color: var(--text);
  transition: var(--transition);
}

.pdf-viewer-close:hover {
  background: var(--primary);
  color: #fff;
}

.pdf-viewer-scroll {
  height: 100%;
  overflow-y: auto;
  padding: 64px 16px 32px;
  box-sizing: border-box;
  background: var(--bg-light);
}

.pdf-viewer-scroll img {
  display: block;
  width: 100%;
  max-width: 1400px;
  margin: 0 auto 16px;
  border-radius: 6px;
  box-shadow: var(--shadow-md);
}