/* 采购鲸 - 自动化配件传动配件采购平台 */
/* 海洋蓝主题风格 */

:root {
  /* 主色调：海洋蓝 */
  --primary: #0c4a6e;
  --primary-deep: #082f49;
  --primary-light: #075985;
  --primary-surface: #0ea5e9;
  --primary-bg: #f0f9ff;
  
  /* 强调色：海洋蓝渐变 */
  --accent: #0284c7;
  --accent-light: #38bdf8;
  --accent-glow: rgba(2, 132, 199, 0.25);
  --accent-soft: #e0f2fe;
  
  /* 中性色 */
  --text: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-inverse: #ffffff;
  
  /* 背景色 */
  --bg: #f8fafc;
  --bg-alt: #f0f9ff;
  --bg-card: #ffffff;
  --bg-dark: #082f49;
  
  /* 边框与阴影 */
  --border: #e2e8f0;
  --border-light: #f1f5f9;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow: 0 4px 20px rgba(2, 132, 199, 0.08);
  --shadow-lg: 0 12px 40px rgba(2, 132, 199, 0.12);
  --shadow-xl: 0 20px 60px rgba(2, 132, 199, 0.16);
  --shadow-glow: 0 0 30px rgba(2, 132, 199, 0.15);
  
  /* 圆角 */
  --radius-sm: 4px;
  --radius: 8px;
  --radius-lg: 12px;
  --radius-xl: 20px;
  
  /* 布局 */
  --max-width: 1280px;
  --header-height: 72px;
  
  /* 过渡 */
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-fast: all 0.15s ease;
}

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

html { 
  scroll-behavior: smooth; 
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.8;
  font-size: 15px;
  font-weight: 400;
  letter-spacing: 0.01em;
}

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

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

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

.container { 
  max-width: var(--max-width); 
  margin: 0 auto; 
  padding: 0 32px; 
}

/* ==================== 头部导航 ==================== */
.site-header {
  background: rgba(8, 47, 73, 0.98);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: var(--text-inverse);
  position: sticky;
  top: 0;
  z-index: 1000;
  height: var(--header-height);
  border-bottom: 1px solid rgba(14, 165, 233, 0.2);
  transition: var(--transition);
}

.site-header.scrolled {
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.2);
}

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

.logo { 
  display: flex; 
  align-items: center;
  text-decoration: none;
  color: white;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 2px;
}



.main-nav ul { 
  display: flex; 
  gap: 36px; 
  list-style: none;
}

.main-nav a { 
  color: rgba(255, 255, 255, 0.8); 
  font-size: 14px; 
  font-weight: 500;
  letter-spacing: 0.5px;
  position: relative;
  padding: 4px 0;
}

.main-nav a::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-light);
  transition: var(--transition);
}

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

.main-nav a:hover::after,
.main-nav a.active::after {
  width: 100%;
}

.mobile-menu-btn { 
  display: none; 
  background: none; 
  border: none; 
  color: var(--text-inverse); 
  font-size: 28px; 
  cursor: pointer;
  padding: 8px;
}

/* ==================== Hero 区域 ==================== */
.hero {
  background: linear-gradient(160deg, var(--primary-deep) 0%, var(--primary) 40%, var(--primary-light) 100%);
  color: var(--text-inverse);
  padding: 140px 0 100px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

/* 背景装饰 */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: 
    radial-gradient(circle at 20% 50%, rgba(14, 165, 233, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(56, 189, 248, 0.1) 0%, transparent 40%),
    url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.02'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.6;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 120px;
  background: linear-gradient(to top, var(--bg), transparent);
}

.hero .container { 
  position: relative; 
  z-index: 2; 
}

.hero-badge {
  display: inline-block;
  background: rgba(14, 165, 233, 0.15);
  border: 1px solid rgba(14, 165, 233, 0.3);
  color: var(--accent-light);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 2px;
  padding: 8px 20px;
  border-radius: 30px;
  margin-bottom: 32px;
  text-transform: uppercase;
}

.hero h1 { 
  font-size: 48px; 
  font-weight: 700; 
  margin-bottom: 20px; 
  letter-spacing: 1px;
  line-height: 1.2;
  background: linear-gradient(135deg, #ffffff 0%, var(--accent-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero .lead { 
  font-size: 17px; 
  color: rgba(255, 255, 255, 0.7); 
  max-width: 680px; 
  margin: 0 auto 40px;
  line-height: 1.8;
}

.hero-cta { 
  display: flex; 
  gap: 20px; 
  justify-content: center;
  flex-wrap: wrap;
}

/* ==================== 按钮系统 ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.5px;
  transition: var(--transition);
  border: 2px solid transparent;
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.1), transparent);
  opacity: 0;
  transition: var(--transition-fast);
}

.btn:hover::before { opacity: 1; }

.btn-primary { 
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-light) 100%);
  color: var(--text-inverse);
  border-color: var(--accent);
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover { 
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(2, 132, 199, 0.3);
  color: var(--text-inverse);
}

.btn-outline { 
  background: transparent; 
  color: var(--text-inverse); 
  border-color: rgba(255, 255, 255, 0.3);
}

.btn-outline:hover { 
  background: rgba(255, 255, 255, 0.08);
  border-color: var(--accent-light);
  color: var(--accent-light);
}

.btn-ghost {
  background: transparent;
  color: var(--accent);
  border-color: transparent;
  padding: 10px 20px;
}

.btn-ghost:hover {
  background: var(--bg-alt);
  color: var(--primary);
}

/* ==================== 板块系统 ==================== */
.section { 
  padding: 100px 0; 
  position: relative;
}

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

.section-divider {
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  margin: 0 auto 24px;
  border-radius: 2px;
}

.section-title { 
  text-align: center; 
  margin-bottom: 64px; 
}

.section-title .section-divider {
  margin-bottom: 24px;
}

.section-title h2 { 
  font-size: 36px; 
  font-weight: 700; 
  color: var(--primary); 
  margin-bottom: 16px;
  letter-spacing: 0.5px;
}

.section-title p { 
  color: var(--text-muted); 
  font-size: 16px; 
  max-width: 640px; 
  margin: 0 auto;
  line-height: 1.8;
}

.section-title.left { text-align: left; }
.section-title.left .section-divider { margin-left: 0; }
.section-title.left p { margin-left: 0; }

/* ==================== 卡片系统 ==================== */
.card-grid { 
  display: grid; 
  grid-template-columns: repeat(4, 1fr); 
  gap: 24px; 
}

@media (max-width: 1200px) {
  .card-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 900px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .card-grid {
    grid-template-columns: 1fr;
  }
}

/* 品牌卡片特殊布局 - 确保一行显示多个 */
.brand-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 32px 24px;
  transition: var(--transition);
}

.brand-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-top: 3px solid var(--accent);
}

.brand-logo {
  min-width: 80px;
  min-height: 56px;
  padding: 12px 24px;
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 20px;
  box-shadow: 0 4px 12px rgba(2, 132, 199, 0.2);
  letter-spacing: 1px;
  text-align: center;
  word-break: keep-all;
}

.brand-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
}

.brand-origin {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 16px;
  padding: 4px 12px;
  background: var(--accent-soft);
  border-radius: 20px;
}

.brand-desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.card-link {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  font-size: 14px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: var(--transition-fast);
}

.card-link:hover {
  color: var(--primary);
  gap: 10px;
}

.card-link::after {
  content: "→";
  transition: var(--transition-fast);
}

.card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 36px 32px;
  transition: var(--transition);
  border: 1px solid var(--border-light);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  opacity: 0;
  transition: var(--transition-fast);
}

.card:hover { 
  transform: translateY(-6px); 
  box-shadow: var(--shadow-xl);
  border-color: rgba(14, 165, 233, 0.2);
}

.card:hover::before { opacity: 1; }

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--accent-soft), rgba(14, 165, 233, 0.08));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  font-size: 24px;
  margin-bottom: 24px;
}

.card h3 { 
  font-size: 20px; 
  color: var(--primary); 
  margin-bottom: 12px;
  font-weight: 600;
  line-height: 1.4;
}

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

.card .tag {
  display: inline-block;
  font-size: 11px;
  color: var(--accent);
  background: rgba(14, 165, 233, 0.08);
  padding: 4px 12px;
  border-radius: 20px;
  margin-bottom: 16px;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.card .card-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 20px;
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
}

.card .card-link::after {
  content: "→";
  transition: var(--transition-fast);
}

.card .card-link:hover::after {
  transform: translateX(4px);
}

/* ==================== 品牌卡片 ==================== */
.brand-card { 
  display: flex; 
  flex-direction: column;
  text-align: center;
  padding: 40px 32px;
}

.brand-card .brand-logo {
  min-width: 80px;
  min-height: 56px;
  padding: 12px 24px;
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 24px;
  font-size: 20px;
  font-weight: 700;
  color: white;
  letter-spacing: 1px;
  text-align: center;
  word-break: keep-all;
}

.brand-card .brand-name { 
  font-size: 24px; 
  font-weight: 700; 
  color: var(--primary); 
  margin-bottom: 8px;
  letter-spacing: 0.5px;
}

.brand-card .brand-origin { 
  font-size: 12px; 
  color: var(--accent); 
  text-transform: uppercase; 
  letter-spacing: 2px; 
  margin-bottom: 16px;
  font-weight: 600;
}

.brand-card .brand-desc { 
  flex: 1; 
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 20px;
}

/* ==================== 行业标签 ==================== */
.industry-tags { 
  display: flex; 
  flex-wrap: wrap; 
  gap: 16px; 
  justify-content: center; 
}

.industry-tag {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 40px;
  padding: 12px 28px;
  font-size: 14px;
  color: var(--text);
  font-weight: 500;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  cursor: pointer;
}

.industry-tag:hover { 
  background: var(--primary); 
  color: var(--text-inverse); 
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

/* ==================== 表格 ==================== */
.table-wrap { 
  overflow-x: auto; 
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  border: 1px solid var(--border-light);
}

.data-table { 
  width: 100%; 
  border-collapse: collapse; 
  background: var(--bg-card);
  font-size: 14px;
}

.data-table th { 
  background: var(--primary); 
  color: var(--text-inverse); 
  font-weight: 600; 
  font-size: 13px;
  padding: 16px 20px; 
  text-align: left;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.data-table th:first-child {
  border-radius: var(--radius-lg) 0 0 0;
}

.data-table th:last-child {
  border-radius: 0 var(--radius-lg) 0 0;
}

.data-table td { 
  padding: 16px 20px; 
  border-bottom: 1px solid var(--border-light); 
  color: var(--text);
  vertical-align: top;
}

.data-table tr:last-child td { 
  border-bottom: none; 
}

.data-table tr:hover td { 
  background: rgba(14, 165, 233, 0.03); 
}

.data-table tr:nth-child(even) td {
  background: rgba(0, 0, 0, 0.01);
}

.data-table tr:nth-child(even):hover td {
  background: rgba(14, 165, 233, 0.03);
}

/* ==================== 文章详情 ==================== */
.article-content { 
  max-width: 860px; 
  margin: 0 auto; 
  background: var(--bg-card); 
  padding: 60px 72px; 
  border-radius: var(--radius-lg); 
  box-shadow: var(--shadow);
  border: 1px solid var(--border-light);
}

.article-content h1 { 
  font-size: 36px; 
  color: var(--primary); 
  margin-bottom: 20px; 
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: 0.3px;
}

.article-content h2 { 
  font-size: 24px; 
  color: var(--primary); 
  margin: 48px 0 20px; 
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border-light);
  font-weight: 600;
  position: relative;
}

.article-content h2::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 60px;
  height: 2px;
  background: var(--accent);
}

.article-content h3 { 
  font-size: 20px; 
  color: var(--primary); 
  margin: 32px 0 14px;
  font-weight: 600;
}

.article-content p { 
  margin-bottom: 18px; 
  color: var(--text);
  line-height: 1.9;
}

.article-content ul, 
.article-content ol { 
  margin: 16px 0 24px 24px; 
}

.article-content li { 
  margin-bottom: 10px;
  line-height: 1.8;
  color: var(--text-secondary);
}

.article-content .meta { 
  color: var(--text-muted); 
  font-size: 13px; 
  margin-bottom: 40px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-light);
}

/* ==================== FAQ ==================== */
.faq-item { 
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  margin-bottom: 16px;
  overflow: hidden;
  transition: var(--transition-fast);
}

.faq-item:hover {
  border-color: rgba(14, 165, 233, 0.2);
}

.faq-question { 
  padding: 20px 24px; 
  font-weight: 600; 
  color: var(--primary); 
  cursor: pointer; 
  display: flex; 
  justify-content: space-between; 
  align-items: center;
  font-size: 15px;
  transition: var(--transition-fast);
}

.faq-question:hover {
  color: var(--accent);
}

.faq-question span {
  font-size: 20px;
  color: var(--accent);
  transition: transform 0.3s ease;
}

.faq-item.open .faq-question span {
  transform: rotate(45deg);
}

.faq-answer { 
  padding: 0 24px 20px; 
  color: var(--text-secondary); 
  font-size: 14px;
  line-height: 1.8;
  display: none;
}

.faq-item.open .faq-answer {
  display: block;
}

/* ==================== 面包屑 ==================== */
.breadcrumb { 
  background: var(--bg-alt); 
  padding: 16px 0; 
  font-size: 13px; 
  color: var(--text-muted);
  border-bottom: 1px solid var(--border-light);
}

.breadcrumb .container {
  display: flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb a { 
  color: var(--text-muted); 
}

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

.breadcrumb .separator {
  color: var(--border);
  margin: 0 4px;
}

/* ==================== 页脚 ==================== */
.site-footer { 
  background: var(--primary-deep); 
  color: rgba(255, 255, 255, 0.6); 
  padding: 80px 0 32px; 
  font-size: 14px; 
}

.footer-grid { 
  display: grid; 
  grid-template-columns: 2fr 1fr 1fr 1fr; 
  gap: 56px; 
  margin-bottom: 56px; 
}

.footer-brand h3 { 
  color: var(--text-inverse); 
  font-size: 20px; 
  margin-bottom: 20px;
  letter-spacing: 1px;
}

.footer-brand p { 
  line-height: 1.9; 
  margin-bottom: 20px;
  color: rgba(255, 255, 255, 0.5);
}

.footer-col h4 { 
  color: var(--accent-light); 
  font-size: 13px; 
  text-transform: uppercase; 
  letter-spacing: 2px; 
  margin-bottom: 24px;
  font-weight: 600;
}

.footer-col ul { 
  list-style: none; 
}

.footer-col li { 
  margin-bottom: 12px; 
}

.footer-col a { 
  color: rgba(255, 255, 255, 0.5); 
  font-size: 14px;
  transition: var(--transition-fast);
}

.footer-col a:hover { 
  color: var(--accent-light); 
  padding-left: 4px;
}

.footer-bottom { 
  border-top: 1px solid rgba(255, 255, 255, 0.08); 
  padding-top: 32px; 
  text-align: center; 
  color: rgba(255, 255, 255, 0.3); 
  font-size: 13px;
  line-height: 1.8;
}

/* ==================== 表单 ==================== */
.form-group { 
  margin-bottom: 24px; 
}

.form-group label { 
  display: block; 
  font-weight: 600; 
  margin-bottom: 8px; 
  font-size: 14px; 
  color: var(--primary);
  letter-spacing: 0.3px;
}

.form-group input, 
.form-group select, 
.form-group textarea {
  width: 100%;
  padding: 14px 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 14px;
  background: var(--bg-card);
  transition: var(--transition-fast);
  font-family: inherit;
}

.form-group input:focus, 
.form-group select:focus, 
.form-group textarea:focus { 
  outline: none; 
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.1);
}

.form-inline { 
  display: flex; 
  gap: 16px; 
  flex-wrap: wrap; 
}

.form-inline .form-group { 
  flex: 1; 
  min-width: 220px; 
}

/* ==================== Callout 提示框 ==================== */
.callout {
  background: linear-gradient(135deg, var(--primary-light), var(--primary));
  color: var(--text-inverse);
  padding: 48px;
  border-radius: var(--radius-lg);
  margin: 48px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(14, 165, 233, 0.15);
}

.callout::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.08), transparent);
  border-radius: 50%;
}

.callout p { 
  margin-bottom: 0; 
  font-size: 16px;
  line-height: 1.8;
  position: relative;
  z-index: 1;
}

.callout strong {
  color: var(--accent-light);
}

.callout a { 
  color: var(--accent-light); 
  font-weight: 600;
  border-bottom: 1px solid transparent;
  transition: var(--transition-fast);
}

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

/* ==================== 列表样式 ==================== */
.check-list { 
  list-style: none; 
}

.check-list li { 
  position: relative; 
  padding-left: 30px; 
  margin-bottom: 12px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.check-list li::before { 
  content: "✓"; 
  position: absolute; 
  left: 0; 
  color: var(--accent); 
  font-weight: 700;
  background: rgba(14, 165, 233, 0.1);
  width: 20px;
  height: 20px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
}

/* ==================== 动画 ==================== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.animate-in {
  animation: fadeInUp 0.6s ease forwards;
  opacity: 0;
}

.animate-in:nth-child(1) { animation-delay: 0.1s; }
.animate-in:nth-child(2) { animation-delay: 0.2s; }
.animate-in:nth-child(3) { animation-delay: 0.3s; }
.animate-in:nth-child(4) { animation-delay: 0.4s; }

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
  .footer-grid { 
    grid-template-columns: 1fr 1fr; 
    gap: 40px;
  }
}

@media (max-width: 768px) {
  :root {
    --header-height: 64px;
  }

  .site-header {
    position: relative;
  }
  
  .main-nav { 
    display: none; 
  }
  
  .main-nav.active {
    display: block;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: rgba(8, 47, 73, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 20px;
    border-top: 1px solid rgba(14, 165, 233, 0.2);
    z-index: 999;
  }
  
  .main-nav.active ul { 
    display: flex; 
    flex-direction: column;
    gap: 0; 
    list-style: none;
    padding: 0;
    margin: 0;
  }

  .main-nav.active li {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  }

  .main-nav.active li:last-child {
    border-bottom: none;
  }

  .main-nav.active a { 
    color: rgba(255, 255, 255, 0.8); 
    font-size: 15px; 
    font-weight: 500;
    letter-spacing: 0.5px;
    padding: 14px 0;
    display: block;
    text-decoration: none;
  }

  .main-nav.active a::after {
    display: none;
  }

  .main-nav.active a:hover, 
  .main-nav.active a.active { 
    color: var(--accent-light); 
  }
  
  .mobile-menu-btn { 
    display: block; 
  }
  
  .hero { 
    padding: 100px 0 80px; 
  }
  
  .hero h1 { 
    font-size: 32px; 
  }
  
  .section { 
    padding: 72px 0; 
  }
  
  .section-title { 
    margin-bottom: 48px; 
  }
  
  .section-title h2 { 
    font-size: 28px; 
  }
  
  .article-content { 
    padding: 40px 28px; 
  }
  
  .article-content h1 {
    font-size: 28px;
  }
  
  .footer-grid { 
    grid-template-columns: 1fr; 
    gap: 36px;
  }
  
  .container {
    padding: 0 20px;
  }
  
  .card-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 26px;
  }
  
  .hero .lead {
    font-size: 15px;
  }
  
  .btn {
    padding: 12px 24px;
    font-size: 13px;
  }
  
  .section-title h2 {
    font-size: 24px;
  }
}

/* ==================== About Page 关于企业 ==================== */
.about-hero {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-deep) 60%, #082f49 100%);
  padding: 80px 0 60px;
  text-align: center;
  color: white;
  position: relative;
  overflow: hidden;
}

.about-hero::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.12) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.about-hero h1 {
  font-size: 40px;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: 2px;
  position: relative;
}

.about-hero .subtitle {
  font-size: 18px;
  color: rgba(255, 255, 255, 0.75);
  letter-spacing: 1px;
}

/* 企业理念 */
.philosophy-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  margin: 48px 0;
}

.philosophy-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 40px 28px;
  text-align: center;
  transition: var(--transition);
}

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

.philosophy-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  background: linear-gradient(135deg, var(--accent-soft), #e0f2fe);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
}

.philosophy-card h3 {
  font-size: 20px;
  color: var(--primary);
  margin-bottom: 12px;
}

.philosophy-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* 发展历程时间轴 */
.timeline {
  position: relative;
  padding: 32px 0;
  margin: 48px 0;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent), var(--accent-light));
  transform: translateX(-50%);
}

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

.timeline-item:nth-child(odd) {
  flex-direction: row;
  padding-right: calc(50% + 40px);
  text-align: right;
}

.timeline-item:nth-child(even) {
  flex-direction: row-reverse;
  padding-left: calc(50% + 40px);
}

.timeline-dot {
  position: absolute;
  left: 50%;
  top: 8px;
  width: 16px;
  height: 16px;
  background: var(--accent);
  border-radius: 50%;
  transform: translateX(-50%);
  z-index: 2;
  border: 3px solid white;
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.timeline-year {
  font-size: 22px;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 8px;
}

.timeline-content {
  background: var(--bg-card);
  padding: 20px 24px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.timeline-content h4 {
  font-size: 16px;
  color: var(--primary);
  margin-bottom: 8px;
}

.timeline-content p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin: 0;
}

/* 关于页 CTA */
.about-cta {
  background: linear-gradient(135deg, var(--accent-soft), #f0f9ff);
  border-radius: var(--radius-lg);
  padding: 48px;
  text-align: center;
  margin: 48px 0;
  border: 1px solid rgba(14, 165, 233, 0.15);
}

.about-cta h2 {
  font-size: 26px;
  color: var(--primary);
  margin-bottom: 12px;
}

.about-cta p {
  color: var(--text-secondary);
  margin-bottom: 24px;
  font-size: 15px;
}

.about-cta .btn {
  margin: 0 8px;
}

/* 公司介绍区 */
.about-intro-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  margin: 40px 0;
  align-items: start;
}

.about-intro-list {
  list-style: none;
  padding: 0;
}

.about-intro-list li {
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 15px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.about-intro-list li::before {
  content: "✓";
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: var(--accent-soft);
  color: var(--accent);
  border-radius: 50%;
  font-size: 12px;
  font-weight: 700;
  flex-shrink: 0;
}

/* 响应式 */
@media (max-width: 768px) {
  .about-hero h1 {
    font-size: 28px;
  }
  
  .philosophy-grid {
    grid-template-columns: 1fr;
  }
  
  .timeline::before {
    left: 20px;
  }
  
  .timeline-item,
  .timeline-item:nth-child(odd),
  .timeline-item:nth-child(even) {
    flex-direction: column;
    padding-left: 50px;
    padding-right: 0;
    text-align: left;
  }
  
  .timeline-dot {
    left: 20px;
  }
  
  .about-intro-grid {
    grid-template-columns: 1fr;
  }
  
  .about-cta {
    padding: 32px 20px;
  }
}