/* ============================================
   西安中试测控科技有限责任公司 - 官方网站
   设计风格：专业工业风 | 蓝灰配色
   ============================================ */

/* === CSS 变量 === */
:root {
  --primary-dark: #0d2b45;
  --primary: #1a3a5c;
  --primary-light: #2c5f8a;
  --accent: #c49b29;
  --accent-light: #e8c44a;
  --white: #ffffff;
  --gray-50: #f8f9fa;
  --gray-100: #f0f2f5;
  --gray-200: #e2e6ea;
  --gray-300: #c8cdd3;
  --gray-400: #9ba3ad;
  --gray-500: #6c757d;
  --gray-600: #495057;
  --gray-700: #343a40;
  --gray-800: #212529;
  --text: #333333;
  --text-light: #666666;
  --bg: #ffffff;
  --bg-alt: #f5f6f8;
  --border: #e2e6ea;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow: 0 2px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --radius-sm: 4px;
  --radius: 8px;
  --radius-lg: 12px;
  --transition: all 0.3s ease;
  --max-width: 1200px;
  --header-height: 72px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

ul, ol {
  list-style: none;
}

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

button {
  cursor: pointer;
  border: none;
  outline: none;
  font-family: inherit;
}

input, textarea, select {
  font-family: inherit;
  outline: none;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* === 顶部工具栏 === */
.top-bar {
  background: var(--primary-dark);
  color: rgba(255,255,255,0.8);
  font-size: 13px;
  padding: 8px 0;
}

.top-bar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.top-bar a {
  color: rgba(255,255,255,0.8);
}

.top-bar a:hover {
  color: var(--accent-light);
}

.top-bar .top-contact span {
  margin-right: 20px;
}

.top-bar .top-contact i {
  margin-right: 4px;
}

/* === 主导航 === */
.main-header {
  background: var(--white);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.main-header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: var(--header-height);
}

.logo {
  display: flex;
  align-items: center;
}

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

.main-nav {
  display: flex;
  align-items: center;
  gap: 0;
}

.main-nav a {
  display: block;
  padding: 8px 18px;
  font-size: 15px;
  color: var(--text);
  font-weight: 500;
  position: relative;
  white-space: nowrap;
}

.main-nav a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 18px;
  right: 18px;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transition: transform 0.3s ease;
}

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

.main-nav a:hover::after,
.main-nav a.active::after {
  transform: scaleX(1);
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  padding: 5px;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--primary-dark);
  transition: var(--transition);
}

/* === 页面横幅 === */
.page-banner {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: var(--white);
  padding: 60px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.page-banner::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: rgba(255,255,255,0.03);
}

.page-banner::after {
  content: "";
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: rgba(255,255,255,0.03);
}

.page-banner h2 {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 12px;
  position: relative;
  z-index: 1;
}

.page-banner .breadcrumb {
  font-size: 14px;
  color: rgba(255,255,255,0.7);
  position: relative;
  z-index: 1;
}

.page-banner .breadcrumb a {
  color: rgba(255,255,255,0.9);
}

.page-banner .breadcrumb a:hover {
  color: var(--accent-light);
}

/* === 章节标题 === */
.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  font-size: 32px;
  font-weight: 700;
  color: var(--primary-dark);
  margin-bottom: 12px;
}

.section-title .title-line {
  width: 60px;
  height: 3px;
  background: var(--accent);
  margin: 0 auto 16px;
}

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

/* === Hero 轮播 === */
.hero {
  position: relative;
  height: 520px;
  overflow: hidden;
}

.hero-slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 0.8s ease;
  display: flex;
  align-items: center;
}

.hero-slide.active {
  opacity: 1;
}

.hero-slide:nth-child(1) {
  background: linear-gradient(135deg, #0d2b45 0%, #1a3a5c 40%, #2c5f8a 100%);
}

.hero-slide:nth-child(2) {
  background: linear-gradient(135deg, #1a3a5c 0%, #0d2b45 40%, #1a4a3c 100%);
}

.hero-slide:nth-child(3) {
  background: linear-gradient(135deg, #0d2b45 0%, #1a3a5c 40%, #4a2a1a 100%);
}

.hero-content {
  max-width: 600px;
  color: var(--white);
  position: relative;
  z-index: 2;
}

.hero-content h2 {
  font-size: 44px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 20px;
  animation: fadeInUp 0.6s ease;
}

.hero-content p {
  font-size: 17px;
  line-height: 1.8;
  opacity: 0.9;
  margin-bottom: 32px;
  animation: fadeInUp 0.6s ease 0.2s both;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  animation: fadeInUp 0.6s ease 0.4s both;
}

.hero-pattern {
  position: absolute;
  right: 0;
  top: 0;
  width: 45%;
  height: 100%;
  opacity: 0.06;
  background: repeating-linear-gradient(
    45deg,
    transparent,
    transparent 10px,
    rgba(255,255,255,0.5) 10px,
    rgba(255,255,255,0.5) 11px
  );
}

.hero-dots {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 10px;
  z-index: 3;
}

.hero-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: rgba(255,255,255,0.4);
  cursor: pointer;
  transition: var(--transition);
}

.hero-dot.active {
  background: var(--accent);
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* === 按钮 === */
.btn {
  display: inline-block;
  padding: 12px 32px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  transition: var(--transition);
  text-align: center;
}

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

.btn-primary:hover {
  background: var(--accent-light);
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(196,155,41,0.3);
}

.btn-outline {
  border: 2px solid var(--white);
  color: var(--white);
}

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

.btn-outline-dark {
  border: 2px solid var(--primary);
  color: var(--primary);
}

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

.btn-sm {
  padding: 8px 20px;
  font-size: 13px;
}

/* === 通用 section === */
section {
  padding: 80px 0;
}

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

/* === 首页 - 公司简介 === */
.about-preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-image {
  position: relative;
}

.about-image .img-placeholder {
  background: linear-gradient(135deg, var(--gray-200), var(--gray-300));
  border-radius: var(--radius-lg);
  height: 380px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-500);
  font-size: 16px;
}

.about-image .exp-badge {
  position: absolute;
  bottom: -20px;
  right: -20px;
  background: var(--primary);
  color: var(--white);
  padding: 24px 28px;
  border-radius: var(--radius);
  text-align: center;
}

.about-image .exp-badge .num {
  font-size: 36px;
  font-weight: 700;
  display: block;
  line-height: 1;
}

.about-image .exp-badge .label {
  font-size: 13px;
  opacity: 0.8;
  margin-top: 4px;
}

.about-text h3 {
  font-size: 28px;
  color: var(--primary-dark);
  margin-bottom: 8px;
}

.about-text .subtitle {
  color: var(--accent);
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 20px;
}

.about-text p {
  color: var(--text-light);
  margin-bottom: 16px;
  line-height: 1.9;
}

/* === 产品分类卡片 === */
.product-categories {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 24px;
}

.category-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 36px 24px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}

.category-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.category-card .cat-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  font-size: 28px;
}

.category-card h4 {
  font-size: 17px;
  color: var(--primary-dark);
  margin-bottom: 8px;
}

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

/* === 优势 === */
.advantages {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
}

.advantage-item {
  text-align: center;
  padding: 32px 20px;
}

.advantage-item .adv-icon {
  font-size: 42px;
  margin-bottom: 16px;
}

.advantage-item h4 {
  font-size: 18px;
  color: var(--primary-dark);
  margin-bottom: 10px;
}

.advantage-item p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.7;
}

/* === 行业应用 === */
.industry-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
}

.industry-item {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 12px;
  text-align: center;
  transition: var(--transition);
  font-size: 14px;
  color: var(--text);
}

.industry-item:hover {
  border-color: var(--primary-light);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.industry-item .ind-icon {
  font-size: 28px;
  margin-bottom: 8px;
  display: block;
}

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

.news-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}

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

.news-card .news-img {
  height: 200px;
  background: linear-gradient(135deg, var(--gray-200), var(--gray-300));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-500);
  font-size: 14px;
  overflow: hidden;
}

.news-card .news-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.news-card .news-body {
  padding: 20px;
}

.news-card .news-date {
  font-size: 12px;
  color: var(--gray-500);
  margin-bottom: 8px;
}

.news-card h4 {
  font-size: 16px;
  color: var(--primary-dark);
  margin-bottom: 8px;
  line-height: 1.5;
}

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

/* === 页脚 === */
.main-footer {
  background: var(--primary-dark);
  color: rgba(255,255,255,0.7);
  padding-top: 60px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  padding-bottom: 40px;
}

.footer-col h4 {
  color: var(--white);
  font-size: 17px;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 12px;
}

.footer-col h4::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 30px;
  height: 2px;
  background: var(--accent);
}

.footer-col p {
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 8px;
}

.footer-col a {
  display: block;
  font-size: 14px;
  color: rgba(255,255,255,0.6);
  padding: 6px 0;
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--accent-light);
  padding-left: 6px;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 0;
  text-align: center;
  font-size: 13px;
  color: rgba(255,255,255,0.5);
}

.footer-bottom a {
  color: rgba(255,255,255,0.6);
}

.footer-bottom a:hover {
  color: var(--accent-light);
}

/* === 关于我们页 === */
.about-section {
  padding: 80px 0;
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-grid.reverse {
  direction: rtl;
}

.about-grid.reverse > * {
  direction: ltr;
}

/* 时间轴 */
.timeline {
  position: relative;
  padding: 20px 0;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border);
  transform: translateX(-50%);
}

.timeline-item {
  display: flex;
  align-items: flex-start;
  margin-bottom: 40px;
  position: relative;
}

.timeline-item:nth-child(odd) {
  flex-direction: row;
}

.timeline-item:nth-child(even) {
  flex-direction: row-reverse;
}

.timeline-item .timeline-dot {
  position: absolute;
  left: 50%;
  top: 8px;
  width: 14px;
  height: 14px;
  background: var(--accent);
  border-radius: 50%;
  transform: translateX(-50%);
  z-index: 2;
  border: 3px solid var(--white);
  box-shadow: var(--shadow-sm);
}

.timeline-item .timeline-content {
  width: 45%;
  padding: 24px;
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
}

.timeline-item .timeline-year {
  font-size: 14px;
  color: var(--accent);
  font-weight: 700;
  margin-bottom: 4px;
}

.timeline-item h4 {
  font-size: 18px;
  color: var(--primary-dark);
  margin-bottom: 8px;
}

.timeline-item p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.7;
}

/* 文化价值观 */
.values-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}

.value-card {
  text-align: center;
  padding: 40px 24px;
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}

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

.value-card .value-icon {
  font-size: 44px;
  margin-bottom: 16px;
}

.value-card h4 {
  font-size: 20px;
  color: var(--primary-dark);
  margin-bottom: 12px;
}

.value-card p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.7;
}

/* === 产品页 === */
.product-filters {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 10px 24px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 30px;
  font-size: 14px;
  color: var(--text);
  cursor: pointer;
  transition: var(--transition);
}

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

.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.product-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}

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

.product-card .product-img {
  height: 240px;
  background: linear-gradient(135deg, var(--gray-100), var(--gray-200));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-400);
  font-size: 14px;
  position: relative;
  overflow: hidden;
}

.product-card .product-img img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #fff;
  transition: transform 0.4s ease;
}

.product-card:hover .product-img img {
  transform: scale(1.05);
}

.product-card .product-img .product-tag {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--accent);
  color: var(--white);
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
}

.product-card .product-body {
  padding: 20px;
}

.product-card .product-body h4 {
  font-size: 17px;
  color: var(--primary-dark);
  margin-bottom: 8px;
}

.product-card .product-body .product-spec {
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 4px;
  line-height: 1.6;
}

.product-card .product-body .product-link {
  display: inline-block;
  margin-top: 12px;
  color: var(--primary);
  font-size: 14px;
  font-weight: 600;
}

.product-card .product-body .product-link:hover {
  color: var(--accent);
}

/* === 产品详情页 === */
.product-detail-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  padding: 60px 0;
}

.product-gallery .gallery-main {
  height: 400px;
  background: linear-gradient(135deg, var(--gray-100), var(--gray-200));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-400);
  margin-bottom: 16px;
  overflow: hidden;
}

.product-gallery .gallery-main img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #fff;
}

.product-info h3 {
  font-size: 28px;
  color: var(--primary-dark);
  margin-bottom: 12px;
}

.product-info .product-model {
  font-size: 14px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 20px;
}

.product-info .product-desc {
  font-size: 15px;
  color: var(--text-light);
  line-height: 1.9;
  margin-bottom: 24px;
}

.spec-table {
  width: 100%;
  border-collapse: collapse;
  margin: 32px 0;
}

.spec-table th,
.spec-table td {
  padding: 12px 16px;
  border: 1px solid var(--border);
  font-size: 14px;
}

.spec-table th {
  background: var(--bg-alt);
  color: var(--primary-dark);
  font-weight: 600;
  text-align: left;
  width: 30%;
}

.spec-table td {
  color: var(--text-light);
}

.feature-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin: 24px 0;
}

.feature-list li {
  padding: 8px 0;
  font-size: 14px;
  color: var(--text-light);
}

.feature-list li::before {
  content: "✓";
  color: var(--accent);
  font-weight: 700;
  margin-right: 8px;
}

/* Tab 切换 */
.product-tabs {
  border-bottom: 2px solid var(--border);
  margin-bottom: 32px;
  display: flex;
  gap: 0;
}

.product-tabs button {
  padding: 14px 32px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text-light);
  background: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: var(--transition);
}

.product-tabs button:hover {
  color: var(--primary);
}

.product-tabs button.active {
  color: var(--primary);
  border-bottom-color: var(--accent);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

/* === 新闻列表页 === */
.news-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.news-list-item {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid var(--border);
}

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

.news-list-item .news-thumb {
  height: 180px;
  background: linear-gradient(135deg, var(--gray-100), var(--gray-200));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-400);
  font-size: 14px;
  overflow: hidden;
}

.news-list-item .news-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.news-list-item .news-info {
  padding: 20px;
}

.news-list-item .news-info .date {
  font-size: 12px;
  color: var(--gray-500);
  margin-bottom: 8px;
}

.news-list-item .news-info h4 {
  font-size: 16px;
  color: var(--primary-dark);
  margin-bottom: 8px;
  line-height: 1.5;
}

.news-list-item .news-info p {
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.6;
}

/* === 联系我们页 === */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 60px;
  padding: 60px 0;
}

.contact-info-cards {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.contact-info-card {
  display: flex;
  gap: 16px;
  padding: 24px;
  background: var(--white);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.contact-info-card:hover {
  box-shadow: var(--shadow);
  border-color: var(--primary-light);
}

.contact-info-card .ci-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  font-size: 20px;
  flex-shrink: 0;
}

.contact-info-card .ci-text h5 {
  font-size: 16px;
  color: var(--primary-dark);
  margin-bottom: 4px;
}

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

/* 联系表单 */
.contact-form {
  background: var(--white);
  padding: 32px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.contact-form h3 {
  font-size: 22px;
  color: var(--primary-dark);
  margin-bottom: 24px;
}

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

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}

.form-group label .required {
  color: #e74c3c;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  transition: var(--transition);
  color: var(--text);
  background: var(--gray-50);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--primary-light);
  box-shadow: 0 0 0 3px rgba(44,95,138,0.1);
  background: var(--white);
}

.form-group textarea {
  min-height: 140px;
  resize: vertical;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

/* === 回到顶部 === */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 44px;
  height: 44px;
  background: var(--primary);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  cursor: pointer;
  opacity: 0;
  transform: translateY(10px);
  transition: var(--transition);
  z-index: 999;
  box-shadow: var(--shadow);
}

.back-to-top.show {
  opacity: 1;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--accent);
}

/* === Toast 提示 === */
.toast {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%);
  background: #27ae60;
  color: var(--white);
  padding: 14px 28px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  z-index: 9999;
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

.toast.show {
  opacity: 1;
}

/* === 响应式 === */
@media (max-width: 1200px) {
  .product-categories { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 1024px) {
  .product-categories { grid-template-columns: repeat(2, 1fr); }
  .advantages { grid-template-columns: repeat(2, 1fr); }
  .industry-grid { grid-template-columns: repeat(3, 1fr); }
  .news-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .values-grid { grid-template-columns: repeat(2, 1fr); }
  .product-grid { grid-template-columns: repeat(2, 1fr); }
  .news-list { grid-template-columns: repeat(2, 1fr); }
  .product-detail-layout { grid-template-columns: 1fr; }
  .about-preview { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; }
  .contact-layout { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  :root { --header-height: 60px; }

  .top-bar { display: none; }

  .main-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--white);
    flex-direction: column;
    padding: 20px;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    z-index: 999;
  }

  .main-nav.open {
    transform: translateX(0);
  }

  .main-nav a {
    padding: 14px 0;
    border-bottom: 1px solid var(--border);
    font-size: 16px;
  }

  .menu-toggle { display: flex; }

  .hero { height: 400px; }
  .hero-content h2 { font-size: 28px; }
  .hero-content p { font-size: 15px; }
  .hero-buttons { flex-direction: column; }

  .product-categories { grid-template-columns: 1fr; }
  .advantages { grid-template-columns: 1fr; }
  .industry-grid { grid-template-columns: repeat(2, 1fr); }
  .news-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .values-grid { grid-template-columns: 1fr; }
  .product-grid { grid-template-columns: 1fr; }
  .news-list { grid-template-columns: 1fr; }
  .feature-list { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .product-filters { gap: 8px; }
  .filter-btn { padding: 8px 16px; font-size: 13px; }

  section { padding: 50px 0; }
  .section-title h2 { font-size: 26px; }
  .page-banner h2 { font-size: 28px; }

  .timeline::before { left: 20px; }
  .timeline-item { flex-direction: column !important; padding-left: 50px; }
  .timeline-item .timeline-dot { left: 20px; }
  .timeline-item .timeline-content { width: 100%; }
}

@media (max-width: 480px) {
  .industry-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-content h2 { font-size: 24px; }
  .section-title h2 { font-size: 22px; }
}