/* ========== CSS Variables / Design Tokens ========== */
:root {
  /* 原站配色：深蓝导航 + 蓝色主色 + 橙色强调 */
  --color-primary: #1c3a6b;        /* 导航栏深蓝 */
  --color-primary-light: #24508a;  /* 导航下拉深蓝 */
  --color-accent: #0066cc;         /* 主色蓝 */
  --color-accent-bright: #ff6600;  /* 橙色强调/按钮 */
  --color-bg: #ffffff;
  --color-bg-alt: #f5f7fa;
  --color-bg-section: #f0f4f8;
  --color-text: #333333;
  --color-text-light: #666666;
  --color-text-muted: #999999;
  --color-border: #e0e0e0;
  --color-link: #0066cc;
  --container-width: 1200px;
  --gutter: 20px;
  --radius: 6px;
  --transition: 0.3s ease;
}

/* ========== Reset & Base ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  font-size: 14px;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--color-link); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--color-accent-bright); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

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

/* ========== Buttons ========== */
.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 500;
  text-align: center;
  transition: all var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
}
.btn-primary {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}
.btn-primary:hover {
  background: #0052a3;
  border-color: #0052a3;
  color: #fff;
}
.btn-outline {
  background: transparent;
  color: var(--color-accent);
  border-color: var(--color-accent);
}
.btn-outline:hover {
  background: var(--color-accent);
  color: #fff;
}
.btn-cta {
  background: var(--color-accent-bright);
  color: #fff;
  border-color: var(--color-accent-bright);
  padding: 14px 36px;
  font-size: 18px;
  font-weight: 600;
  border-radius: 4px;
}
.btn-cta:hover { background: #e55a00; border-color: #e55a00; color: #fff; }

/* ========== Header ========== */
.header {
  background: var(--color-primary);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}
.logo { display: flex; align-items: center; color: #fff; }
.logo:hover { color: #fff; }
.logo-text { display: flex; flex-direction: column; }
.logo-cn { font-size: 22px; font-weight: 700; letter-spacing: 2px; }
.logo-en { font-size: 10px; letter-spacing: 3px; opacity: 0.7; text-transform: uppercase; }

.main-nav { flex: 1; display: flex; justify-content: center; }
.nav-list {
  display: flex;
  gap: 4px;
  align-items: center;
}
.nav-item > a {
  display: block;
  padding: 8px 16px;
  color: rgba(255,255,255,0.85);
  font-size: 15px;
  border-radius: 4px;
  transition: all var(--transition);
  white-space: nowrap;
}
.nav-item > a:hover,
.nav-item.active > a {
  color: #fff;
  background: rgba(255,255,255,0.1);
}

/* Dropdown */
.has-dropdown { position: relative; }
.dropdown {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--color-primary-light);
  min-width: 220px;
  border-radius: 0 0 var(--radius) var(--radius);
  box-shadow: 0 8px 24px rgba(0,0,0,0.2);
  z-index: 100;
  padding: 8px 0;
}
.has-dropdown:hover .dropdown { display: block; }
.dropdown li a {
  display: block;
  padding: 8px 20px;
  color: rgba(255,255,255,0.85);
  font-size: 13px;
  transition: all var(--transition);
}
.dropdown li a:hover {
  color: #fff;
  background: rgba(255,255,255,0.08);
  padding-left: 24px;
}

/* Header actions */
.header-actions { display: flex; align-items: center; gap: 16px; }
.hotline {
  display: flex; align-items: center; gap: 6px;
  color: var(--color-accent-bright); font-weight: 600; font-size: 14px;
  white-space: nowrap;
}
.hotline:hover { color: #fff; }
.lang-switch {
  color: rgba(255,255,255,0.7);
  font-size: 13px;
  padding: 4px 10px;
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 4px;
  transition: all var(--transition);
}
.lang-switch:hover { color: #fff; border-color: #fff; }

/* Mobile nav toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  flex-direction: column;
  gap: 5px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: all var(--transition);
}

/* ========== About Page Hero ========== */
.hero {
  background: linear-gradient(135deg, #1c3a6b 0%, #24508a 100%);
  color: #fff;
  padding: 60px 0;
}
.hero .hero-content { text-align: center; margin-bottom: 40px; }
.hero .hero-content h1 { color: #fff; font-size: 36px; font-weight: 700; margin-bottom: 12px; }
.hero .hero-content p { color: rgba(255,255,255,0.85); font-size: 16px; line-height: 1.8; }
.hero .hero-stats {
  display: flex;
  justify-content: space-around;
  align-items: center;
  gap: 40px;
  flex-wrap: wrap;
}

/* ========== Hero Carousel ========== */
.hero-carousel {
  position: relative;
  color: #fff;
  overflow: hidden;
}
.carousel-wrapper {
  position: relative;
  width: 100%;
  min-height: 500px;
}
.carousel-slides {
  position: relative;
  width: 100%;
  height: 500px;
}
.carousel-slide {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 100%;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  opacity: 0;
  transition: opacity 0.8s ease;
  z-index: 0;
}
.carousel-slide.active {
  opacity: 1;
  z-index: 1;
}
.slide-overlay {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: linear-gradient(135deg, rgba(28,58,107,0.65) 0%, rgba(0,102,204,0.35) 60%, rgba(26,127,212,0.2) 100%);
  z-index: 1;
}
.slide-content {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
  height: 100%;
  padding-top: 60px;
  max-width: 600px;
}
.slide-content h1 {
  font-size: 36px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 16px;
  text-shadow: 0 2px 8px rgba(0,0,0,0.3);
}
.slide-content p {
  font-size: 16px;
  opacity: 0.9;
  margin-bottom: 28px;
  line-height: 1.8;
  text-shadow: 0 1px 4px rgba(0,0,0,0.2);
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-actions .btn-outline { color: #fff; border-color: rgba(255,255,255,0.5); }
.hero-actions .btn-outline:hover { background: #fff; color: var(--color-primary); border-color: #fff; }

/* Carousel Controls */
.carousel-controls {
  position: absolute;
  top: 50%;
  left: 0; right: 0;
  z-index: 10;
  display: flex;
  justify-content: space-between;
  padding: 0 30px;
  transform: translateY(-50%);
  pointer-events: none;
}
.carousel-prev, .carousel-next {
  pointer-events: all;
  background: rgba(255,255,255,0.2);
  color: #fff;
  border: none;
  width: 44px;
  height: 44px;
  font-size: 22px;
  border-radius: 50%;
  cursor: pointer;
  transition: all var(--transition);
  backdrop-filter: blur(4px);
}
.carousel-prev:hover, .carousel-next:hover {
  background: rgba(255,255,255,0.4);
}
.carousel-indicators {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
  display: flex;
  gap: 10px;
}
.indicator {
  width: 36px;
  height: 4px;
  background: rgba(255,255,255,0.4);
  border: none;
  border-radius: 2px;
  cursor: pointer;
  transition: all var(--transition);
}
.indicator.active {
  background: #ff6600;
  width: 48px;
}

/* Stats Bar */
.hero-stats-bar {
  background: linear-gradient(90deg, #1c3a6b 0%, #24508a 100%);
  padding: 24px 0;
  position: relative;
  z-index: 2;
}
.hero-stats-bar .container {
  display: flex;
  justify-content: space-around;
  align-items: center;
  gap: 40px;
}
.stat-item { text-align: center; }
.stat-item strong {
  display: block;
  font-size: 42px;
  font-weight: 700;
  line-height: 1;
  color: #ffaa44;
}
.stat-item strong span { font-size: 16px; font-weight: 400; color: rgba(255,255,255,0.7); }
.stat-item > span { display: block; font-size: 13px; color: rgba(255,255,255,0.6); margin-top: 6px; }

/* ========== Sections ========== */
.section { padding: 60px 0; }
.section-alt { background: var(--color-bg-alt); }
.section-title {
  text-align: center;
  font-size: 28px;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 8px;
}
.section-subtitle {
  text-align: center;
  color: var(--color-text-muted);
  font-size: 15px;
  margin-bottom: 36px;
}
.section-action { text-align: center; margin-top: 36px; }

/* ========== Product Categories ========== */
.cat-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-bottom: 32px;
}
.cat-tab {
  padding: 10px 22px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 50px;
  font-size: 14px;
  color: var(--color-text-light);
  cursor: pointer;
  transition: all var(--transition);
}
.cat-tab:hover { border-color: var(--color-accent); color: var(--color-accent); }
.cat-tab.active {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}

.cat-panel { display: none; }
.cat-panel.active { display: block; }

.product-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--gutter);
}

.product-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}
.product-card:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.1);
  transform: translateY(-4px);
}
.card-img {
  position: relative;
  background: var(--color-bg-alt);
  aspect-ratio: 1/1;
  overflow: hidden;
}
.card-img img { width: 100%; height: 100%; object-fit: contain; padding: 16px; box-sizing: border-box; }
.card-badge {
  position: absolute;
  top: 12px;
  right: 12px;
  background: var(--color-accent-bright);
  color: #fff;
  padding: 3px 10px;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 500;
}
.card-body { padding: 16px; }
.card-body h3 { font-size: 14px; font-weight: 600; line-height: 1.4; margin-bottom: 4px; color: var(--color-text); }
.card-model { color: var(--color-accent); font-size: 13px; font-weight: 500; margin-bottom: 8px; }
.card-specs { margin-bottom: 12px; }
.card-specs li {
  font-size: 12px;
  color: var(--color-text-light);
  padding: 2px 0;
  padding-left: 14px;
  position: relative;
}
.card-specs li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent);
  opacity: 0.4;
}
.card-link { font-size: 13px; font-weight: 500; color: var(--color-accent); }
.card-link:hover { color: var(--color-accent-bright); }

/* ========== Page Banner ========== */
.page-banner {
  background: linear-gradient(135deg, #1c3a6b 0%, #24508a 100%);
  color: #fff;
  padding: 48px 0;
  text-align: center;
}
.page-banner h1 { font-size: 32px; font-weight: 700; margin-bottom: 8px; }
.page-banner p { font-size: 15px; opacity: 0.85; }

/* ========== Product Category Cards (products page) ========== */
.cat-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
  margin-top: 32px;
}
.cat-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}
.cat-card:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.1);
  transform: translateY(-4px);
}
.cat-card-link { display: block; text-decoration: none; color: inherit; }
.cat-card-img {
  width: 100%;
  aspect-ratio: 1 / 1;
  overflow: hidden;
  background: var(--color-bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
}
.cat-card-img img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  padding: 12px;
  box-sizing: border-box;
  transition: transform 0.4s ease;
}
.cat-card:hover .cat-card-img img { transform: scale(1.05); }
.cat-card-body { padding: 20px; }
.cat-card-body h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; color: var(--color-text); }
.cat-card-body p { font-size: 13px; color: var(--color-text-light); line-height: 1.6; margin-bottom: 12px; }
.cat-card-link-text { font-size: 13px; font-weight: 500; color: var(--color-accent); }
.cat-card-link-text:hover { color: var(--color-accent-bright); }

/* More categories */
.more-cats { margin-top: 48px; text-align: center; }
.more-cats h3 { font-size: 20px; font-weight: 600; margin-bottom: 20px; color: var(--color-text); }
.more-cats-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}
.more-cat-item {
  display: inline-block;
  padding: 10px 24px;
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 50px;
  font-size: 14px;
  color: var(--color-text-light);
  text-decoration: none;
  transition: all var(--transition);
}
.more-cat-item:hover {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}

/* ========== Why Choose Us ========== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 20px;
}
.feature-item {
  text-align: center;
  padding: 28px 20px;
  background: var(--color-bg);
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  transition: all var(--transition);
}
.feature-item:hover {
  box-shadow: 0 4px 16px rgba(0,0,0,0.08);
  transform: translateY(-2px);
}
.feature-icon { margin-bottom: 16px; }
.feature-item h3 { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.feature-item p { font-size: 13px; color: var(--color-text-light); line-height: 1.6; }

/* ========== News ========== */
.news-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}
.news-col-title {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-accent);
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: 20px;
}
.news-item { margin-bottom: 20px; }
.news-item a { display: block; color: var(--color-text); }
.news-item a:hover { color: var(--color-accent); }
.news-item h4 { font-size: 15px; font-weight: 500; margin-bottom: 4px; line-height: 1.5; }
.news-item time { font-size: 12px; color: var(--color-text-muted); display: block; margin-bottom: 6px; }
.news-item p { font-size: 13px; color: var(--color-text-light); line-height: 1.6; }

/* ========== About Brief ========== */
.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: start;
}
.about-text h2 { text-align: left; font-size: 26px; margin-bottom: 16px; }
.about-text p { margin-bottom: 12px; color: var(--color-text-light); line-height: 1.8; }
.highlight { color: var(--color-accent); font-weight: 500; }
.about-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.tag {
  padding: 4px 14px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 50px;
  font-size: 12px;
  color: var(--color-text-light);
}
.about-certs h3 { font-size: 18px; font-weight: 600; margin-bottom: 16px; }
.cert-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.cert-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 13px;
}
.cert-icon { color: var(--color-accent); font-size: 14px; }

/* ========== CTA ========== */
.cta-section {
  background: linear-gradient(90deg, #1c3a6b 0%, #0066cc 100%);
  color: #fff;
  padding: 60px 0;
}
.cta-section h2 { color: #fff; font-size: 26px; }

/* ========== Footer ========== */
.footer {
  background: var(--color-primary);
  color: rgba(255,255,255,0.7);
  padding: 50px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-logo { margin-bottom: 16px; }
.footer-logo .logo-cn { font-size: 20px; font-weight: 700; color: #fff; }
.footer-logo .logo-en { font-size: 10px; color: rgba(255,255,255,0.5); letter-spacing: 2px; }
.footer-hotline { font-size: 12px; color: rgba(255,255,255,0.5); margin-top: 12px; }
.footer-phone { display: block; font-size: 24px; font-weight: 700; color: var(--color-accent-bright); margin: 4px 0 12px; }
.footer-phone:hover { color: #fff; }
.footer-addr { font-size: 13px; line-height: 1.7; }
.footer-col h3 {
  font-size: 15px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 16px;
}
.footer-col ul li { margin-bottom: 8px; }
.footer-col ul li a { color: rgba(255,255,255,0.65); font-size: 13px; transition: all var(--transition); }
.footer-col ul li a:hover { color: #fff; padding-left: 4px; }
.footer-qr { margin-top: 16px; }
.qr-placeholder {
  width: 100px;
  height: 100px;
  background: rgba(255,255,255,0.1);
  border: 1px dashed rgba(255,255,255,0.2);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  color: rgba(255,255,255,0.4);
  text-align: center;
}
.footer-bottom {
  padding: 20px 0;
  text-align: center;
  font-size: 12px;
  color: rgba(255,255,255,0.35);
}
.footer-bottom a { color: rgba(255,255,255,0.5); }
.footer-bottom a:hover { color: #fff; }
.footer-bottom p + p { margin-top: 4px; }

/* ========== Responsive ========== */
@media (max-width: 1024px) {
  .product-grid { grid-template-columns: repeat(3, 1fr); }
  .cat-grid { grid-template-columns: repeat(2, 1fr); }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); gap: 30px; }
}

@media (max-width: 768px) {
  .header-inner { height: 60px; }
  .main-nav { display: none; position: fixed; top: 60px; left: 0; right: 0; bottom: 0; background: var(--color-primary); z-index: 999; overflow-y: auto; }
  .main-nav.open { display: block; }
  .nav-list { flex-direction: column; padding: 20px; gap: 0; }
  .nav-item > a { padding: 12px 16px; border-radius: 0; border-bottom: 1px solid rgba(255,255,255,0.05); }
  .dropdown { display: none; position: static; box-shadow: none; background: rgba(0,0,0,0.2); padding: 0; }
  .has-dropdown.open .dropdown { display: block; }
  .nav-toggle { display: flex; }
  .header-actions { display: none; }

  .carousel-slides { height: 320px; }
  .slide-content h1 { font-size: 24px; }
  .slide-content p { font-size: 14px; }
  .carousel-prev, .carousel-next { width: 32px; height: 32px; font-size: 16px; }
  .hero-stats-bar { padding: 16px 0; }
  .hero-stats-bar .container { gap: 20px; flex-wrap: wrap; }
  .hero { padding: 40px 0; }
  .hero .hero-content h1 { font-size: 26px; }
  .hero .hero-stats { gap: 20px; }
  .stat-item strong { font-size: 28px; }

  .section { padding: 40px 0; }
  .section-title { font-size: 22px; }
  .product-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
  .cat-grid { grid-template-columns: 1fr; gap: 20px; }
  .features-grid { grid-template-columns: 1fr 1fr; gap: 12px; }
  .news-grid { grid-template-columns: 1fr; gap: 30px; }
  .about-grid { grid-template-columns: 1fr; gap: 30px; }
  .cert-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
}

@media (max-width: 480px) {
  .product-grid { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; }
  .cat-tabs { gap: 6px; }
  .cat-tab { padding: 8px 14px; font-size: 12px; }
}