/* ==========================================================================
   浙江伯达尼科技有限公司 - 官网主样式
   视觉风格参考火山引擎 (volcengine.com)
   ========================================================================== */

/* ---------- 设计 Token ---------- */
:root {
  /* 背景与表面 */
  --bg: #ffffff;
  --surface: #ffffff;
  --surface-soft: #f4f8fc;
  --surface-muted: #f2f6fa;

  /* 文字 */
  --text: #0c0d0e;
  --text-2: #42464e;
  --text-3: #737a87;
  --text-4: #c7ccd6;

  /* 线条 */
  --line: #eaedf1;
  --line-strong: #dde2e9;

  /* 品牌色 */
  --brand: #1664ff;
  --brand-hover: #005eff;
  --dark: #0c0d0e;

  /* 阴影（唯一签名阴影） */
  --shadow: 0 24px 80px rgba(12, 13, 14, .06);

  /* 圆角 */
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 8px;
  --radius-xl: 12px;

  /* 布局 */
  --container-max: 1280px;
  --header-height: 60px;
  --transition: .24s ease;
}

/* ---------- 重置 ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
               -apple-system, BlinkMacSystemFont, "Segoe UI",
               Helvetica Neue, Arial, sans-serif;
  font-size: 16px;
  font-weight: 400;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
a { color: inherit; text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--brand); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
input, textarea, select { font-family: inherit; font-size: inherit; }

/* ---------- 布局 ---------- */
.container {
  width: min(var(--container-max), calc(100vw - 80px));
  margin: 0 auto;
}
.section { padding: 100px 0; }
.section--tight { padding: 70px 0; }
.section--soft { background: var(--surface-soft); }

.section-title {
  font-size: 48px;
  font-weight: 300;
  line-height: 1.3;
  margin-bottom: 16px;
  text-align: center;
}
.section-title::after {
  content: "";
  display: block;
  width: 160px;
  height: 1px;
  margin: 24px auto 0;
  background: repeating-linear-gradient(90deg, var(--text-3) 0 4px, transparent 4px 8px);
  opacity: .3;
}
.section-subtitle {
  font-size: 18px;
  font-weight: 300;
  color: var(--text-3);
  text-align: center;
  margin-bottom: 56px;
}

/* ---------- 顶栏（磨砂玻璃） ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-height);
  background: rgba(255, 255, 255, .72);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
  z-index: 50;
}
.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 500;
  color: var(--text);
}
.logo-mark {
  width: 40px; height: 40px;
  background: var(--dark);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  overflow: hidden;
  padding: 3px;
}
.logo-mark svg { width: 100%; height: 100%; display: block; }
.logo-text { line-height: 1.1; }
.logo-text .cn { font-size: 16px; font-weight: 500; }
.logo-text .en { font-size: 11px; color: var(--text-3); font-weight: 400; letter-spacing: .5px; }

/* 主导航 */
.main-nav { display: flex; align-items: center; gap: 4px; }
.nav-item { position: relative; }
.nav-link {
  display: block;
  padding: 0 16px;
  height: var(--header-height);
  line-height: var(--header-height);
  font-size: 15px;
  font-weight: 400;
  color: var(--text);
  transition: color var(--transition);
}
.nav-link:hover,
.nav-item.active .nav-link { color: var(--brand); }
.nav-item.has-dropdown .nav-link::after {
  content: "";
  display: inline-block;
  width: 6px; height: 6px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg) translateY(-2px);
  margin-left: 6px;
  vertical-align: middle;
}

/* 下拉菜单 */
.dropdown {
  position: absolute;
  top: 100%; left: 0;
  min-width: 180px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 8px 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity var(--transition), transform var(--transition), visibility var(--transition);
  box-shadow: 0 12px 40px rgba(12, 13, 14, .06);
}
.nav-item:hover .dropdown { opacity: 1; visibility: visible; transform: translateY(0); }
.dropdown a {
  display: block;
  padding: 10px 20px;
  font-size: 14px;
  color: var(--text-2);
  transition: background var(--transition), color var(--transition);
}
.dropdown a:hover { background: var(--surface-soft); color: var(--brand); }

/* 顶栏右侧 */
.header-cta { display: flex; align-items: center; gap: 12px; }
.header-cta .btn { height: 36px; padding: 0 18px; font-size: 14px; }

/* 汉堡按钮（移动端） */
.menu-toggle { display: none; font-size: 24px; color: var(--text); padding: 4px 8px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 48px;
  padding: 0 28px;
  font-size: 16px;
  font-weight: 400;
  border-radius: var(--radius-md);
  transition: all var(--transition);
  white-space: nowrap;
}
.btn-primary {
  background: var(--dark);
  color: #fff;
}
.btn-primary:hover { background: #2a2b2e; color: #fff; }
.btn-secondary {
  background: #fff;
  color: var(--text);
  border: 1px solid var(--line-strong);
}
.btn-secondary:hover { border-color: var(--text); color: var(--text); }
.btn-light {
  background: rgba(255,255,255,.1);
  color: #fff;
  border: 1px solid rgba(255,255,255,.4);
}
.btn-light:hover { background: rgba(255,255,255,.18); color: #fff; }
.btn-sm { height: 40px; padding: 0 20px; font-size: 14px; }
.btn-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 15px;
  color: var(--text);
  border-bottom: 1px solid var(--text);
  padding-bottom: 2px;
  transition: color var(--transition), border-color var(--transition);
}
.btn-link:hover { color: var(--brand); border-color: var(--brand); }
.btn-link::after { content: "→"; }

/* ---------- Hero 区 ---------- */
.hero {
  position: relative;
  min-height: 600px;
  padding: 140px 0 80px;
  background: var(--surface-soft);
  overflow: hidden;
}
.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.hero-copy { max-width: 560px; }
.hero-eyebrow {
  font-size: 14px;
  color: var(--brand);
  font-weight: 500;
  letter-spacing: 1px;
  margin-bottom: 20px;
}
.hero-title {
  font-size: 64px;
  font-weight: 300;
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -.5px;
}
.hero-title-en {
  font-size: 28px;
  font-weight: 300;
  color: var(--text-3);
  margin-bottom: 28px;
  letter-spacing: .5px;
}
.hero-desc {
  font-size: 16px;
  color: var(--text-2);
  line-height: 1.7;
  margin-bottom: 40px;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-media {
  position: relative;
  aspect-ratio: 4/3;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.hero-media img { width: 100%; height: 100%; object-fit: cover; }

/* ---------- 产品矩阵 ---------- */
.product-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}
.product-card {
  padding: 48px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  transition: background var(--transition);
  display: flex;
  flex-direction: column;
}
.product-card:hover { background: var(--surface-soft); }
.product-card .product-img {
  aspect-ratio: 16/10;
  background: var(--surface-muted);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: 24px;
}
.product-card .product-img img { width: 100%; height: 100%; object-fit: cover; }
.product-card .product-model {
  font-size: 13px;
  color: var(--brand);
  font-weight: 500;
  letter-spacing: .5px;
  margin-bottom: 8px;
}
.product-card .product-name {
  font-size: 22px;
  font-weight: 400;
  margin-bottom: 12px;
}
.product-card .product-desc {
  font-size: 15px;
  color: var(--text-2);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

/* ---------- 暗色对比块 ---------- */
.dark-panel {
  background: var(--dark);
  color: #fff;
  padding: 80px 64px;
  border-radius: var(--radius-xl);
}
.dark-panel .panel-eyebrow {
  font-size: 13px;
  color: rgba(255,255,255,.6);
  letter-spacing: 1px;
  margin-bottom: 16px;
}
.dark-panel .panel-title {
  font-size: 40px;
  font-weight: 300;
  line-height: 1.2;
  margin-bottom: 12px;
}
.dark-panel .panel-title-en {
  font-size: 20px;
  font-weight: 300;
  color: rgba(255,255,255,.6);
  margin-bottom: 48px;
}
.metric-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 48px;
}
.metric-item { border-top: 1px solid rgba(255,255,255,.15); padding-top: 24px; }
.metric-value {
  font-size: 48px;
  font-weight: 300;
  line-height: 1.1;
  margin-bottom: 8px;
  letter-spacing: -.5px;
  white-space: nowrap;
}
.metric-label {
  font-size: 14px;
  color: rgba(255,255,255,.7);
}

/* ---------- 数据区 ---------- */
.data-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 40px;
}
.data-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 40px;
  text-align: center;
}
.data-value {
  font-size: 48px;
  font-weight: 300;
  color: var(--text);
  line-height: 1.1;
  margin-bottom: 12px;
  letter-spacing: -.5px;
}
.data-label { font-size: 15px; color: var(--text-2); }
.data-desc {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
  font-size: 16px;
  color: var(--text-2);
  line-height: 1.7;
}

/* ---------- 证书网格 ---------- */
.cert-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.cert-card {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 32px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: border-color var(--transition);
}
.cert-card:hover { border-color: var(--line-strong); }
.cert-icon {
  flex-shrink: 0;
  width: 72px; height: 72px;
  background: var(--surface-soft);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 500;
  color: var(--brand);
  text-align: center;
  line-height: 1.2;
}
.cert-info .cert-name { font-size: 20px; font-weight: 400; margin-bottom: 6px; }
.cert-info .cert-desc { font-size: 14px; color: var(--text-3); line-height: 1.5; }

/* ---------- 优势卡片 ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature-card {
  padding: 40px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}
.feature-card:hover { border-color: var(--line-strong); background: var(--surface-soft); }
.feature-icon {
  width: 48px; height: 48px;
  margin-bottom: 24px;
  color: var(--brand);
}
.feature-title { font-size: 20px; font-weight: 400; margin-bottom: 12px; }
.feature-list { font-size: 14px; color: var(--text-2); line-height: 1.8; }
.feature-list li { padding-left: 16px; position: relative; }
.feature-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 11px;
  width: 4px; height: 4px;
  background: var(--brand);
  border-radius: 50%;
}

/* ---------- CTA 区 ---------- */
.cta-section { text-align: center; padding: 100px 0; }
.cta-title { font-size: 40px; font-weight: 300; margin-bottom: 16px; }
.cta-subtitle { font-size: 16px; color: var(--text-3); margin-bottom: 40px; }
.cta-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--dark);
  color: rgba(255,255,255,.7);
  padding: 80px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 48px;
  margin-bottom: 56px;
}
.footer-brand .logo { color: #fff; margin-bottom: 20px; }
.footer-brand .logo-text .en { color: rgba(255,255,255,.5); }
.footer-desc { font-size: 14px; line-height: 1.7; max-width: 320px; }
.footer-col h4 {
  font-size: 14px;
  font-weight: 500;
  color: #fff;
  margin-bottom: 20px;
  letter-spacing: .5px;
}
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul li a { font-size: 14px; color: rgba(255,255,255,.6); }
.footer-col ul li a:hover { color: #fff; }
.footer-contact li {
  font-size: 14px;
  color: rgba(255,255,255,.6);
  margin-bottom: 12px;
  line-height: 1.6;
}
.footer-contact .contact-label { color: rgba(255,255,255,.4); display: block; font-size: 12px; margin-bottom: 2px; }
.footer-bottom {
  padding-top: 32px;
  border-top: 1px solid rgba(255,255,255,.1);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: rgba(255,255,255,.4);
}

/* ---------- 内页 Banner ---------- */
.page-banner {
  position: relative;
  height: 320px;
  margin-top: var(--header-height);
  background: var(--dark);
  display: flex;
  align-items: center;
  overflow: hidden;
}
.page-banner img {
  position: absolute;
  inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  opacity: .4;
}
.page-banner .container { position: relative; z-index: 1; }
.page-banner .banner-title { font-size: 44px; font-weight: 300; color: #fff; margin-bottom: 8px; }
.page-banner .banner-title-en { font-size: 18px; font-weight: 300; color: rgba(255,255,255,.6); letter-spacing: 1px; }
.breadcrumb {
  margin-top: 16px;
  font-size: 13px;
  color: rgba(255,255,255,.6);
}
.breadcrumb a:hover { color: #fff; }
.breadcrumb span { margin: 0 8px; }

/* ---------- 锚点 Tab 导航（走进伯达尼/技术实力） ---------- */
.anchor-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 56px;
  padding: 80px 0;
}
.anchor-nav { position: sticky; top: calc(var(--header-height) + 24px); align-self: start; }
.anchor-nav ul { border-left: 1px solid var(--line); }
.anchor-nav li a {
  display: block;
  padding: 12px 20px;
  font-size: 15px;
  color: var(--text-2);
  border-left: 2px solid transparent;
  margin-left: -1px;
  transition: all var(--transition);
}
.anchor-nav li a:hover { color: var(--text); }
.anchor-nav li a.active { color: var(--brand); border-left-color: var(--brand); font-weight: 500; }
.anchor-panel { display: none; }
.anchor-panel.active { display: block; animation: fadeIn .3s ease; }
.anchor-panel h2 {
  font-size: 32px;
  font-weight: 300;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}
.anchor-panel h3 { font-size: 20px; font-weight: 400; margin: 32px 0 16px; }
.anchor-panel p { font-size: 16px; color: var(--text-2); line-height: 1.8; margin-bottom: 16px; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

/* ---------- 通用 Tab（产品中心/新闻中心） ---------- */
.tab-bar {
  display: flex;
  gap: 8px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 48px;
  overflow-x: auto;
}
.tab-btn {
  padding: 16px 24px;
  font-size: 15px;
  color: var(--text-2);
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  white-space: nowrap;
  transition: all var(--transition);
}
.tab-btn:hover { color: var(--text); }
.tab-btn.active { color: var(--brand); border-bottom-color: var(--brand); font-weight: 500; }
.tab-panel { display: none; }
.tab-panel.active { display: block; animation: fadeIn .3s ease; }

/* ---------- 产品详情 ---------- */
.product-detail { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; margin-bottom: 48px; }
.product-detail .product-img {
  aspect-ratio: 4/3;
  background: var(--surface-muted);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.product-detail .product-img img { width: 100%; height: 100%; object-fit: cover; }
.product-info h3 { font-size: 28px; font-weight: 400; margin-bottom: 8px; }
.product-info .product-model { font-size: 14px; color: var(--brand); margin-bottom: 20px; }
.product-info p { font-size: 15px; color: var(--text-2); line-height: 1.8; margin-bottom: 16px; }

/* 参数表 */
.param-table { width: 100%; border-collapse: collapse; margin: 24px 0; }
.param-table th, .param-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}
.param-table th { color: var(--text-3); font-weight: 400; }
.param-table td { color: var(--text); font-weight: 500; }
/* 双列布局（每行仅一个 th + 一个 td）：首列占40% */
.param-table tr > th:first-child:nth-last-child(2),
.param-table tr > td:first-child:nth-last-child(2) { width: 40%; }

/* 应用场景卡 */
.app-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 24px; }
.app-card { padding: 20px; background: var(--surface-soft); border-radius: var(--radius-md); }
.app-card .app-title { font-size: 14px; font-weight: 500; margin-bottom: 6px; }
.app-card .app-desc { font-size: 13px; color: var(--text-3); }

/* ---------- 新闻列表 ---------- */
.news-list { display: flex; flex-direction: column; }
.news-item {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 32px;
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
  transition: background var(--transition);
}
.news-item:hover { background: var(--surface-soft); padding-left: 16px; padding-right: 16px; }
.news-item .news-img {
  aspect-ratio: 16/10;
  background: var(--surface-muted);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.news-item .news-img img { width: 100%; height: 100%; object-fit: cover; }
.news-item .news-date { font-size: 13px; color: var(--text-3); margin-bottom: 8px; }
.news-item .news-title { font-size: 20px; font-weight: 400; margin-bottom: 10px; transition: color var(--transition); }
.news-item:hover .news-title { color: var(--brand); }
.news-item .news-summary { font-size: 14px; color: var(--text-2); line-height: 1.7; }

/* ---------- 留言表单 ---------- */
.form-section { padding: 80px 0; }
.form-wrap { max-width: 720px; margin: 0 auto; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; margin-bottom: 24px; }
.form-group { margin-bottom: 24px; }
.form-label { display: block; font-size: 14px; color: var(--text-2); margin-bottom: 8px; }
.form-label .req { color: var(--brand); }
.form-input, .form-textarea, .form-select {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-md);
  font-size: 15px;
  color: var(--text);
  background: #fff;
  transition: border-color var(--transition);
}
.form-input:focus, .form-textarea:focus, .form-select:focus { outline: none; border-color: var(--brand); }
.form-textarea { resize: vertical; min-height: 120px; }
.form-success {
  display: none;
  padding: 16px 20px;
  background: #ecfdf5;
  border: 1px solid #abf5d1;
  border-radius: var(--radius-md);
  color: #065f46;
  font-size: 14px;
  margin-bottom: 24px;
}
.form-success.show { display: block; }

/* ---------- 联系我们 ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; padding: 80px 0; }
.contact-info { display: flex; flex-direction: column; gap: 32px; }
.contact-card {
  padding: 32px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
}
.contact-card .contact-icon { font-size: 24px; margin-bottom: 16px; color: var(--brand); }
.contact-card .contact-name { font-size: 18px; font-weight: 400; margin-bottom: 8px; }
.contact-card .contact-value { font-size: 16px; color: var(--text-2); line-height: 1.6; }
.contact-map {
  aspect-ratio: 4/3;
  background: var(--surface-soft);
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  overflow: hidden;
}
.contact-map iframe { width: 100%; height: 100%; border: 0; }

/* ---------- 占位提示 ---------- */
.placeholder-note {
  padding: 24px;
  background: #fffbeb;
  border: 1px dashed #f0a50f;
  border-radius: var(--radius-md);
  color: #92400e;
  font-size: 14px;
  line-height: 1.6;
}

/* ---------- 响应式：平板 ---------- */
@media (max-width: 1023px) {
  .container { width: min(var(--container-max), calc(100vw - 48px)); }
  .section { padding: 70px 0; }
  .section-title { font-size: 36px; }
  .hero { padding: 120px 0 60px; }
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero-title { font-size: 48px; }
  .hero-title-en { font-size: 22px; }
  .hero-media { max-width: 560px; }
  .product-card { padding: 32px; }
  .dark-panel { padding: 56px 40px; }
  .dark-panel .panel-title { font-size: 32px; }
  .metric-grid { gap: 24px; }
  .metric-value { font-size: 36px; }
  .data-value { font-size: 36px; }
  .feature-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .anchor-layout { grid-template-columns: 1fr; gap: 32px; }
  .anchor-nav { position: static; }
  .anchor-nav ul { display: flex; overflow-x: auto; border-left: none; border-bottom: 1px solid var(--line); }
  .anchor-nav li a { border-left: none; border-bottom: 2px solid transparent; padding: 12px 16px; margin-left: 0; margin-bottom: -1px; }
  .anchor-nav li a.active { border-left: none; border-bottom-color: var(--brand); }
  .product-detail { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
}

/* ---------- 响应式：手机 ---------- */
@media (max-width: 767px) {
  .container { width: calc(100vw - 32px); }
  .section { padding: 56px 0; }
  .section-title { font-size: 28px; }
  .section-subtitle { font-size: 15px; margin-bottom: 36px; }

  /* 顶栏：汉堡菜单 */
  .menu-toggle { display: block; order: 3; }
  .logo { order: 1; }
  .header-cta { order: 2; }
  .header-cta .btn-secondary { display: none; }
  .main-nav {
    position: fixed;
    top: var(--header-height); left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 16px 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height .3s ease;
    box-shadow: 0 12px 40px rgba(12,13,14,.06);
  }
  .main-nav.open { max-height: calc(100vh - var(--header-height)); overflow-y: auto; }
  .nav-item { width: 100%; }
  .nav-link { height: 48px; line-height: 48px; padding: 0 24px; border-bottom: 1px solid var(--line); }
  .nav-item.has-dropdown .nav-link::after { float: right; margin-top: 22px; }
  .dropdown {
    position: static;
    opacity: 1; visibility: visible; transform: none;
    box-shadow: none;
    border: none;
    border-radius: 0;
    padding: 0;
    background: var(--surface-soft);
    display: none;
  }
  .nav-item.has-dropdown.open .dropdown { display: block; }
  .dropdown a { padding: 12px 40px; border-bottom: 1px solid var(--line); }

  .hero { padding: 100px 0 48px; min-height: auto; }
  .hero-title { font-size: 36px; }
  .hero-title-en { font-size: 18px; }
  .hero-desc { font-size: 15px; }
  .btn { height: 44px; padding: 0 22px; font-size: 15px; }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; }

  .product-grid { grid-template-columns: 1fr; }
  .product-card { padding: 28px 24px; }
  .dark-panel { padding: 40px 24px; border-radius: var(--radius-lg); }
  .dark-panel .panel-title { font-size: 26px; }
  .dark-panel .panel-title-en { font-size: 16px; margin-bottom: 32px; }
  .metric-grid { grid-template-columns: 1fr; gap: 20px; }
  .metric-value { font-size: 32px; }
  .data-grid { grid-template-columns: 1fr; }
  .data-value { font-size: 32px; }
  .cert-grid { grid-template-columns: 1fr; }
  .cert-card { padding: 24px; }

  .cta-title { font-size: 28px; }
  .cta-actions { flex-direction: column; }
  .cta-actions .btn { width: 100%; }

  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; gap: 12px; text-align: center; }

  .page-banner { height: 220px; }
  .page-banner .banner-title { font-size: 30px; }
  .page-banner .banner-title-en { font-size: 14px; }

  .form-row { grid-template-columns: 1fr; gap: 0; }
  .news-item { grid-template-columns: 1fr; gap: 16px; }
  .news-item .news-title { font-size: 18px; }
  .anchor-panel h2 { font-size: 24px; }
  .app-grid { grid-template-columns: 1fr; }
}

/* ==========================================================================
   GSAP 动效启动层（避免 FOUC，并让 GSAP 接管 Tab 面板动画）
   ========================================================================== */

/* 清掉 CSS 中的 fadeIn，由 GSAP 在 Tab 切换时统一接管 */
.anchor-panel,
.tab-panel { animation: none !important; }

/* 减少动效偏好：禁用所有 GSAP 起始隐藏/起始位移 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}