/* ============================================
   聚善仁合集团企业展示网站 - 全局样式
   ============================================ */

/* --- CSS Variables --- */
:root {
  /* 蓝色主色调 */
  --color-primary: #1a6fc4;
  --color-primary-dark: #0e4d8a;
  --color-primary-light: #4a9ae6;
  --color-primary-lighter: #d6e9f8;
  --color-primary-bg: #eef5fc;

  /* 文字色 */
  --color-text: #222;
  --color-text-secondary: #555;
  --color-text-light: #888;
  --color-text-inverse: #fff;

  /* 背景色 */
  --color-bg: #fff;
  --color-bg-alt: #f5f7fa;
  --color-bg-dark: #0c1e35;

  /* 边框与阴影 */
  --color-border: #e0e0e0;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);

  /* 间距 */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2.5rem;
  --spacing-xl: 4rem;
  --spacing-2xl: 6rem;

  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  /* 排版 */
  --font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-size-base: 16px;
  --font-size-sm: 14px;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.5rem;
  --font-size-2xl: 2rem;
  --font-size-3xl: 2.5rem;
  --line-height-base: 1.6;

  /* 导航栏高度 */
  --nav-height: 64px;

  /* 容器最大宽度 */
  --container-max: 1200px;

  /* 过渡 */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
  font-size: var(--font-size-base);
  -webkit-text-size-adjust: 100%;
  /* H5 移动端适配 */
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  /* H5 安全区域适配 */
  padding-bottom: env(safe-area-inset-bottom, 0);
  overflow-x: hidden;
}

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

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

a:hover {
  color: var(--color-primary-dark);
}

ul, ol {
  list-style: none;
}

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

h1, h2, h3, h4, h5, h6 {
  line-height: 1.3;
  color: var(--color-text);
}

/* --- 通用容器 --- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--spacing-sm);
  padding-right: var(--spacing-sm);
}

/* --- 板块通用样式 --- */
.section {
  padding-top: var(--spacing-2xl);
  padding-bottom: var(--spacing-2xl);
}

.section-title {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  text-align: center;
  color: var(--color-text);
  margin-bottom: var(--spacing-lg);
  position: relative;
}

.section-title::after {
  content: "";
  display: block;
  width: 60px;
  height: 3px;
  background-color: var(--color-primary);
  margin: var(--spacing-xs) auto 0;
  border-radius: 2px;
}

/* --- Grid 布局工具类 --- */
.grid {
  display: grid;
  gap: var(--spacing-md);
}

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

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

/* --- Flexbox 布局工具类 --- */
.flex {
  display: flex;
}

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

.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

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

/* --- 间距工具类 --- */
.gap-sm {
  gap: var(--spacing-sm);
}

.gap-md {
  gap: var(--spacing-md);
}

.gap-lg {
  gap: var(--spacing-lg);
}

/* --- 文字对齐 --- */
.text-center {
  text-align: center;
}

/* ============================================
   导航栏样式
   需求: 1.2, 11.1
   ============================================ */

/* Body padding to account for fixed nav */
body {
  padding-top: var(--nav-height);
}

/* Nav bar - fixed top */
#navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  background-color: var(--color-bg);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
}

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

/* Logo */
.nav-logo {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.nav-logo img {
  height: 40px;
  width: auto;
}

/* Nav links */
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.nav-links li a {
  display: block;
  padding: var(--spacing-xs) var(--spacing-sm);
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background-color var(--transition-fast);
  white-space: nowrap;
}

.nav-links li a:hover {
  color: var(--color-primary);
  background-color: var(--color-primary-bg);
}

.nav-links li a.active {
  color: var(--color-primary);
  font-weight: 600;
}

/* Hamburger button - hidden on desktop */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  padding: 4px;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 1px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

/* ============================================
   Hero Section 首屏展示
   需求: 2.1, 2.2, 2.3, 2.4, 11.3
   ============================================ */

.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  margin-top: calc(-1 * var(--nav-height));
  padding-top: var(--nav-height);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: url('sucai/DSC_0025.JPG') center / cover no-repeat;
  color: var(--color-text-inverse);
  overflow: hidden;
}

/* 暗色半透明遮罩 */
.hero-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  z-index: 1;
}

/* 主内容区 */
.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: var(--spacing-lg) var(--spacing-sm);
  max-width: 700px;
}

/* 品牌名称 */
.hero-title {
  font-size: 2.2rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: var(--spacing-md);
  letter-spacing: 0.08em;
  opacity: 0.95;
}

/* 核心数字徽章 - 最突出的元素 */
.hero-core-badge {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 0.15em;
  margin-bottom: var(--spacing-md);
  animation: badgeFadeIn 1s ease-out 0.3s both;
}

.hero-core-number {
  font-size: 6rem;
  font-weight: 800;
  color: #fff;
  line-height: 1;
  text-shadow: 0 4px 20px rgba(26, 111, 196, 0.6), 0 0 60px rgba(26, 111, 196, 0.3);
  background: linear-gradient(135deg, #fff 0%, var(--color-primary-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-core-text {
  font-size: 1.8rem;
  font-weight: 600;
  color: #fff;
  letter-spacing: 0.08em;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

@keyframes badgeFadeIn {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.9);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* 核心标语 */
.hero-tagline {
  font-size: var(--font-size-xl);
  font-weight: 300;
  opacity: 0.85;
  margin-bottom: var(--spacing-lg);
  letter-spacing: 0.15em;
}

/* 数据统计条 */
.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
  animation: badgeFadeIn 1s ease-out 0.6s both;
}

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

.hero-stat-number {
  font-size: 2rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.2;
}

.hero-stat-suffix {
  font-size: 1rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.8);
}

.hero-stat-label {
  display: block;
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.7);
  margin-top: 4px;
  letter-spacing: 0.05em;
}

.hero-stat-divider {
  width: 1px;
  height: 40px;
  background: rgba(255, 255, 255, 0.25);
}

/* CTA 按钮 */
.btn-cta {
  display: inline-block;
  padding: 0.75em 2.5em;
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: #fff;
  background: var(--color-primary);
  border-radius: var(--radius-md);
  transition: background var(--transition-fast), transform var(--transition-fast);
}

.btn-cta:hover {
  background: var(--color-primary-dark);
  color: #fff;
  transform: translateY(-2px);
}

/* 底部照片条 */
.hero-photos {
  position: relative;
  z-index: 2;
  display: flex;
  gap: var(--spacing-xs);
  padding: 0 var(--spacing-sm);
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-lg);
  width: 100%;
  max-width: var(--container-max);
  justify-content: center;
}

.hero-photo-item {
  flex: 1;
  max-width: 220px;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 2px solid rgba(255, 255, 255, 0.3);
  transition: transform var(--transition-base), border-color var(--transition-base);
}

.hero-photo-item:hover {
  transform: translateY(-4px);
  border-color: var(--color-primary-light);
}

.hero-photo-item img {
  width: 100%;
  height: 120px;
  object-fit: cover;
}

/* ============================================
   About Section 关于我们
   需求: 4.1, 4.2, 4.3, 4.4, 11.8
   ============================================ */

.about-layout {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--spacing-xl);
  align-items: start;
}

.about-image img {
  width: 100%;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.about-intro {
  font-size: var(--font-size-lg);
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: var(--spacing-lg);
}

.about-highlight {
  color: var(--color-primary);
  font-style: normal;
  font-weight: 600;
}

.brand-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-sm);
}

.brand-card {
  padding: var(--spacing-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg-alt);
  text-align: center;
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.brand-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.brand-card-title {
  font-size: var(--font-size-sm);
  color: var(--color-primary);
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
}

.brand-card-text {
  font-size: var(--font-size-sm);
  color: var(--color-text);
  line-height: 1.5;
}

/* ============================================
   Service Section 服务能力
   需求: 5.1, 5.2, 5.3, 5.4, 11.3
   ============================================ */

.services-section {
  position: relative;
  background-color: var(--color-bg-alt);
  overflow: hidden;
}

/* 辅助展示背景图 */
.services-bg-photos {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.services-bg-photo {
  position: absolute;
  width: 280px;
  height: 180px;
  object-fit: cover;
  border-radius: var(--radius-lg);
  opacity: 0.08;
}

.services-bg-photo--left {
  top: 10%;
  left: -40px;
  transform: rotate(-6deg);
}

.services-bg-photo--right {
  bottom: 10%;
  right: -40px;
  transform: rotate(4deg);
}

/* 副标题 - 强调核心优势 */
.services-subtitle {
  text-align: center;
  font-size: var(--font-size-xl);
  color: var(--color-primary);
  font-weight: 700;
  margin-top: calc(-1 * var(--spacing-sm));
  margin-bottom: var(--spacing-xl);
  letter-spacing: 0.08em;
  position: relative;
  display: inline-block;
  width: 100%;
}

.services-subtitle::before,
.services-subtitle::after {
  content: "";
  display: inline-block;
  width: 40px;
  height: 2px;
  background: var(--color-primary-light);
  vertical-align: middle;
  margin: 0 var(--spacing-sm);
  opacity: 0.5;
}

/* 服务卡片网格 */
.services-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-md);
  position: relative;
  z-index: 1;
}

/* 单张服务卡片 */
.service-card {
  background: var(--color-bg);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg) var(--spacing-md);
  text-align: center;
  border: 1px solid var(--color-border);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.service-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-6px);
}

/* 图标容器 */
.service-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto var(--spacing-md);
  color: var(--color-primary);
}

.service-icon svg {
  width: 100%;
  height: 100%;
}

/* 卡片标题 */
.service-card-title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--spacing-xs);
}

/* 卡片描述 */
.service-card-desc {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ============================================
   Video Section 宣传片
   需求: 3.1, 3.2, 3.3, 3.4, 11.7
   ============================================ */

.video-wrapper {
  position: relative;
  max-width: 800px;
  margin: 0 auto;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background-color: #000;
  box-shadow: var(--shadow-lg);
}

.video-wrapper video {
  display: block;
  width: 100%;
}

.video-play-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.35);
  cursor: pointer;
  transition: background var(--transition-base);
}

.video-play-overlay:hover {
  background: rgba(0, 0, 0, 0.2);
}

.video-play-overlay .play-icon {
  width: 80px;
  height: 80px;
  transition: transform var(--transition-base);
}

.video-play-overlay:hover .play-icon {
  transform: scale(1.1);
}

.video-play-overlay.hidden {
  display: none;
}

/* ============================================
   Environment Gallery 办公环境画廊
   需求: 6.1, 6.2, 6.3, 6.4, 11.4
   ============================================ */

.env-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-md);
}

.env-card {
  border-radius: var(--radius-md);
  overflow: hidden;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.env-card:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: var(--shadow-lg);
}

.env-card img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
  transition: transform var(--transition-base);
}

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

/* Lazy load placeholder */
img.lazy {
  background-color: #e8e8e8;
}

.env-card img.lazy {
  min-height: 180px;
}

/* ============================================
   Qualification Section 公司资质
   需求: 7.1, 7.2, 7.3, 7.4, 11.5
   ============================================ */

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

.qual-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-md);
}

.qual-card {
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.qual-card:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: var(--shadow-lg);
}

.qual-card img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
  transition: transform var(--transition-base);
}

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

/* Lazy load placeholder */
.qual-card img.lazy {
  min-height: 180px;
}

/* Category tag badge */
.qual-tag {
  position: absolute;
  top: var(--spacing-xs);
  left: var(--spacing-xs);
  padding: 0.2em 0.7em;
  font-size: 12px;
  font-weight: 600;
  color: #fff;
  border-radius: 20px;
  line-height: 1.5;
  pointer-events: none;
}

.qual-tag--tech {
  background-color: var(--color-primary);
}

.qual-tag--security {
  background-color: #e67e22;
}

.qual-tag--copyright {
  background-color: #27ae60;
}

/* ============================================
   Client Section 合作客户
   需求: 8.1, 8.2, 8.3, 11.6
   ============================================ */

.client-grid {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--spacing-xl);
  flex-wrap: wrap;
}

.client-logo {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-md) var(--spacing-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

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

.client-logo img {
  max-width: 200px;
  max-height: 100px;
  object-fit: contain;
  filter: grayscale(100%);
  opacity: 0.7;
  transition: filter var(--transition-base), opacity var(--transition-base);
}

.client-logo:hover img {
  filter: grayscale(0%);
  opacity: 1;
}

/* ============================================
   响应式媒体查询框架
   断点：桌面端（≥1024px）、平板端（768px-1023px）、移动端（<768px）
   需求: 10.1
   ============================================ */

/* --- 平板端 (768px - 1023px) --- */
@media (min-width: 768px) and (max-width: 1023px) {
  :root {
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
  }

  .container {
    padding-left: var(--spacing-md);
    padding-right: var(--spacing-md);
  }

  .section {
    padding-top: var(--spacing-xl);
    padding-bottom: var(--spacing-xl);
  }

  .section-title {
    font-size: 1.75rem;
  }

  /* 导航链接间距缩小 */
  .nav-links {
    gap: 0;
  }

  .nav-links li a {
    padding: var(--spacing-xs) 0.5rem;
    font-size: 14px;
  }

  /* About 平板适配 */
  .about-layout {
    gap: var(--spacing-lg);
  }

  .brand-cards {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Hero 平板适配 */
  .hero-title {
    font-size: 1.8rem;
  }

  .hero-core-number {
    font-size: 4.5rem;
  }

  .hero-core-text {
    font-size: 1.4rem;
  }

  .hero-stats {
    gap: var(--spacing-md);
  }

  .hero-stat-number {
    font-size: 1.6rem;
  }

  .hero-photo-item img {
    height: 100px;
  }

  .hero-photo-item {
    max-width: 180px;
  }

  /* Services 平板适配 */
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Environment 平板适配 */
  .env-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Qualification 平板适配 */
  .qual-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Client 平板适配 */
  .client-grid {
    gap: var(--spacing-lg);
  }

  .client-logo img {
    max-width: 160px;
    max-height: 80px;
  }

  .services-bg-photo {
    width: 200px;
    height: 130px;
  }

  /* 网格列数调整 */
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }

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

/* --- 移动端 (< 768px) --- */
@media (max-width: 767px) {
  :root {
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --font-size-base: 15px;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.75rem;
  }

  .container {
    padding-left: var(--spacing-sm);
    padding-right: var(--spacing-sm);
  }

  .section {
    padding-top: var(--spacing-xl);
    padding-bottom: var(--spacing-xl);
  }

  .section-title {
    font-size: 1.375rem;
  }

  /* 汉堡菜单显示 */
  .hamburger {
    display: flex;
  }

  /* About 移动端适配 */
  .about-layout {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }

  .brand-cards {
    grid-template-columns: repeat(2, 1fr);
  }

  /* Hero 移动端适配 */
  .hero {
    min-height: calc(100vh - var(--nav-height));
    min-height: calc(100dvh - var(--nav-height));
  }

  .hero-title {
    font-size: 1.5rem;
    letter-spacing: 0.05em;
  }

  .hero-core-number {
    font-size: 3.5rem;
  }

  .hero-core-text {
    font-size: 1.1rem;
  }

  .hero-tagline {
    font-size: 0.95rem;
    letter-spacing: 0.1em;
  }

  .hero-stats {
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
  }

  .hero-stat-number {
    font-size: 1.3rem;
  }

  .hero-stat-suffix {
    font-size: 0.8rem;
  }

  .hero-stat-label {
    font-size: 12px;
  }

  .hero-stat-divider {
    height: 30px;
  }

  .hero-content {
    padding: var(--spacing-md) var(--spacing-sm);
  }

  .btn-cta {
    padding: 0.65em 2em;
    font-size: var(--font-size-sm);
  }

  .services-subtitle::before,
  .services-subtitle::after {
    width: 24px;
  }

  .hero-photos {
    flex-wrap: wrap;
    gap: 6px;
    margin-top: var(--spacing-lg);
  }

  .hero-photo-item {
    flex: 0 0 calc(50% - 3px);
    max-width: none;
  }

  .hero-photo-item img {
    height: 80px;
  }

  /* 导航链接折叠 */
  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    width: 100%;
    flex-direction: column;
    background-color: var(--color-bg);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-xs) 0;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links li a {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
    border-radius: 0;
    min-height: 44px;
    display: flex;
    align-items: center;
  }

  .nav-links li a:hover {
    background-color: var(--color-primary-bg);
  }

  /* 汉堡按钮打开状态动画 */
  .hamburger.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .hamburger.active span:nth-child(2) {
    opacity: 0;
  }

  .hamburger.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  /* Services 移动端适配 */
  .services-grid {
    grid-template-columns: 1fr;
  }

  /* Environment 移动端适配 */
  .env-grid {
    grid-template-columns: 1fr;
  }

  /* Qualification 移动端适配 */
  .qual-grid {
    grid-template-columns: 1fr;
  }

  /* Client 移动端适配 */
  .client-grid {
    gap: var(--spacing-md);
  }

  .client-logo {
    padding: var(--spacing-sm) var(--spacing-md);
  }

  .client-logo img {
    max-width: 140px;
    max-height: 70px;
  }

  .services-bg-photo {
    display: none;
  }

  .service-icon {
    width: 52px;
    height: 52px;
  }

  /* Video 移动端适配 */
  .video-play-overlay .play-icon {
    width: 60px;
    height: 60px;
  }

  /* 所有网格变为单列 */
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  /* 确保最小字号 14px */
  body {
    font-size: max(var(--font-size-base), 14px);
  }

  h1 { font-size: var(--font-size-3xl); }
  h2 { font-size: var(--font-size-2xl); }
  h3 { font-size: var(--font-size-xl); }
  h4, h5, h6 { font-size: max(1rem, 14px); }
  small, .qual-tag, .lightbox-counter {
    font-size: 14px;
  }

  /* 品牌卡片移动端单列 */
  .brand-cards {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   Lightbox 灯箱组件
   需求: 6.2, 6.3, 7.2
   ============================================ */

/* 灯箱容器 */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
}

.lightbox[hidden] {
  display: none;
}

/* 全屏遮罩 */
.lightbox-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  cursor: pointer;
}

/* 内容区域 */
.lightbox-content {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  padding: var(--spacing-xl) 60px;
  pointer-events: none;
}

.lightbox-content > * {
  pointer-events: auto;
}

/* 图片包裹容器 */
.lightbox-img-wrapper {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  max-width: 90vw;
  max-height: 80vh;
}

/* 大图 */
.lightbox-img {
  max-width: 90vw;
  max-height: 80vh;
  object-fit: contain;
  border-radius: var(--radius-sm);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
  transition: opacity var(--transition-base);
  user-select: none;
}

.lightbox-img.loading {
  opacity: 0.3;
}

/* 加载指示器 */
.lightbox-spinner {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.lightbox-spinner[hidden] {
  display: none;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* 关闭按钮 */
.lightbox-close {
  position: absolute;
  top: 16px;
  right: 20px;
  font-size: 2.5rem;
  color: #fff;
  background: none;
  border: none;
  cursor: pointer;
  line-height: 1;
  padding: 4px 12px;
  border-radius: var(--radius-sm);
  transition: background var(--transition-fast), transform var(--transition-fast);
  z-index: 10;
}

.lightbox-close:hover {
  background: rgba(255, 255, 255, 0.15);
  transform: scale(1.1);
}

/* 左右切换按钮 */
.lightbox-prev,
.lightbox-next {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  font-size: 2rem;
  color: #fff;
  background: rgba(0, 0, 0, 0.4);
  border: none;
  cursor: pointer;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  transition: background var(--transition-fast), transform var(--transition-fast);
  z-index: 10;
  user-select: none;
}

.lightbox-prev {
  left: 12px;
}

.lightbox-next {
  right: 12px;
}

.lightbox-prev:hover,
.lightbox-next:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* 图片索引计数器 */
.lightbox-counter {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  color: rgba(255, 255, 255, 0.8);
  font-size: var(--font-size-sm);
  background: rgba(0, 0, 0, 0.5);
  padding: 4px 16px;
  border-radius: 20px;
  z-index: 10;
  user-select: none;
}

/* 灯箱移动端适配 */
@media (max-width: 767px) {
  .lightbox-content {
    padding: var(--spacing-lg) 40px;
  }

  .lightbox-prev,
  .lightbox-next {
    font-size: 1.5rem;
    padding: 8px 12px;
  }

  .lightbox-prev {
    left: 4px;
  }

  .lightbox-next {
    right: 4px;
  }

  .lightbox-close {
    top: 8px;
    right: 8px;
    font-size: 2rem;
  }

  .lightbox-counter {
    bottom: 12px;
    font-size: 14px;
  }
}

/* 防止灯箱打开时 body 滚动 */
body.lightbox-open {
  overflow: hidden;
}


/* ============================================
   Contact Section 联系我们
   需求: 9.1, 9.2, 9.3, 11.2
   ============================================ */

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

.contact-layout {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xl);
}

/* 蓝色竖版 LOGO 装饰 */
.contact-logo {
  flex-shrink: 0;
}

.contact-logo img {
  max-height: 260px;
  width: auto;
  filter: drop-shadow(0 4px 12px rgba(26, 111, 196, 0.15));
}

/* 联系信息列表 */
.contact-info {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.contact-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-bg);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.contact-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.contact-icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  color: var(--color-primary);
}

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

.contact-label {
  font-size: var(--font-size-sm);
  color: var(--color-text-light);
  font-weight: 600;
  line-height: 1.4;
}

.contact-value {
  font-size: var(--font-size-lg);
  color: var(--color-text);
  line-height: 1.5;
}

/* ============================================
   Footer 页脚
   需求: 9.3
   ============================================ */

.site-footer {
  background-color: var(--color-bg-dark);
  padding: var(--spacing-lg) 0;
  padding-bottom: calc(var(--spacing-lg) + env(safe-area-inset-bottom, 0));
  text-align: center;
}

.footer-copyright {
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.65);
  letter-spacing: 0.03em;
}

/* --- Contact & Footer 平板端适配 --- */
@media (min-width: 768px) and (max-width: 1023px) {
  .contact-layout {
    gap: var(--spacing-lg);
  }

  .contact-logo img {
    max-height: 200px;
  }
}

/* --- Contact & Footer 移动端适配 --- */
@media (max-width: 767px) {
  .contact-layout {
    flex-direction: column;
    gap: var(--spacing-lg);
  }

  .contact-logo img {
    max-height: 160px;
  }

  .contact-item {
    padding: var(--spacing-sm);
  }

  .contact-value {
    font-size: var(--font-size-base);
  }
}

/* ============================================
   板块滚动进入动画
   需求: 10.2
   ============================================ */

.fade-in-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-up.visible {
  opacity: 1;
  transform: translateY(0);
}