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

:root {
  --primary: #0f2c5c;
  --primary-light: #1a4480;
  --accent: #0ea5e9;
  --accent-light: #38bdf8;
  --accent-dark: #0284c7;
  --dark: #1a1a2e;
  --gray-50: #f8fafc;
  --gray-100: #f1f5f9;
  --gray-200: #e2e8f0;
  --gray-300: #cbd5e1;
  --gray-400: #94a3b8;
  --gray-500: #64748b;
  --gray-600: #475569;
  --gray-700: #334155;
  --gray-800: #1e293b;
  --gray-900: #0f172a;
  --red: #dc2626;
  --green: #16a34a;
  --orange: #ea580c;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.05);
  --shadow: 0 4px 6px -1px rgba(0,0,0,.1), 0 2px 4px -2px rgba(0,0,0,.1);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,.1), 0 4px 6px -4px rgba(0,0,0,.1);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,.1), 0 8px 10px -6px rgba(0,0,0,.1);
  --radius: 8px;
  --radius-lg: 16px;
  --transition: all .3s cubic-bezier(.4,0,.2,1);
}

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Microsoft YaHei", sans-serif;
  color: var(--gray-800);
  line-height: 1.6;
  background: #fff;
  overflow-x: hidden;
}

a { text-decoration: none; color: inherit; }
ul, ol { list-style: none; }
img { max-width: 100%; display: block; }

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ====== 顶部导航 ====== */
.topbar {
  background: var(--primary);
  color: rgba(255,255,255,.85);
  font-size: 13px;
  padding: 8px 0;
}
.topbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.topbar-info { display: flex; gap: 24px; }
.topbar-info span { display: flex; align-items: center; gap: 6px; }
.topbar-info i { color: var(--accent-light); }

/* ====== 主导航 ====== */
.navbar {
  background: #fff;
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: var(--transition);
}
.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
}
.nav-logo .logo-icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 22px;
}
.nav-menu {
  display: flex;
  gap: 8px;
}
.nav-menu a {
  padding: 8px 18px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 500;
  color: var(--gray-700);
  transition: var(--transition);
}
.nav-menu a:hover, .nav-menu a.active {
  color: var(--primary);
  background: var(--gray-100);
}
.nav-toggle {
  display: none;
  font-size: 24px;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--gray-700);
}

/* ====== Hero/Banner ====== */
.hero {
  position: relative;
  min-height: 520px;
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 50%, #1e3a5f 100%);
  color: #fff;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image: 
    radial-gradient(circle at 20% 50%, rgba(14,165,233,.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 30%, rgba(56,189,248,.1) 0%, transparent 50%);
}
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .25;
}
.hero-content {
  position: relative;
  z-index: 1;
  padding: 60px 0;
}
.hero h1 {
  font-size: 48px;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 20px;
  letter-spacing: -1px;
}
.hero .subtitle {
  font-size: 20px;
  color: rgba(255,255,255,.8);
  margin-bottom: 32px;
  max-width: 600px;
}
.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 36px;
}
.hero-tag {
  padding: 6px 16px;
  background: rgba(255,255,255,.1);
  border: 1px solid rgba(255,255,255,.2);
  border-radius: 50px;
  font-size: 14px;
  backdrop-filter: blur(10px);
}
.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: var(--radius);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: none;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover {
  background: var(--accent-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(14,165,233,.4);
}
.btn-outline {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255,255,255,.4);
}
.btn-outline:hover {
  background: rgba(255,255,255,.1);
  border-color: rgba(255,255,255,.8);
}
.btn-dark {
  background: var(--primary);
  color: #fff;
}
.btn-dark:hover {
  background: var(--primary-light);
}

/* ====== 通用 Section ====== */
.section {
  padding: 80px 0;
}
.section-header {
  text-align: center;
  margin-bottom: 56px;
}
.section-header .eyebrow {
  display: inline-block;
  font-size: 14px;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 12px;
}
.section-header h2 {
  font-size: 36px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 16px;
}
.section-header p {
  font-size: 17px;
  color: var(--gray-500);
  max-width: 600px;
  margin: 0 auto;
}

/* ====== 数据统计 ====== */
.stats {
  background: var(--primary);
  padding: 48px 0;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}
.stat-item .stat-number {
  font-size: 44px;
  font-weight: 800;
  color: var(--accent-light);
  line-height: 1;
}
.stat-item .stat-label {
  font-size: 15px;
  color: rgba(255,255,255,.7);
  margin-top: 8px;
}

/* ====== 产品网格 ====== */
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 28px;
}
.product-card {
  background: #fff;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition);
  cursor: pointer;
}
.product-card:hover {
  box-shadow: var(--shadow-xl);
  transform: translateY(-4px);
  border-color: var(--accent);
}
.product-image {
  height: 220px;
  background: linear-gradient(135deg, var(--gray-100), var(--gray-200));
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
}
.product-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.product-image .placeholder {
  font-size: 64px;
  color: var(--gray-300);
}
.product-card .badge {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--accent);
  color: #fff;
  padding: 4px 12px;
  border-radius: 50px;
  font-size: 12px;
  font-weight: 600;
}
.product-body {
  padding: 24px;
}
.product-body h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 8px;
}
.product-body p {
  font-size: 14px;
  color: var(--gray-500);
  margin-bottom: 16px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.product-features {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.product-features span {
  font-size: 12px;
  padding: 3px 10px;
  background: var(--gray-100);
  border-radius: 50px;
  color: var(--gray-600);
}

/* =====> 优势卡片 ====== */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.advantage-card {
  text-align: center;
  padding: 36px 24px;
  background: #fff;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  transition: var(--transition);
}
.advantage-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}
.advantage-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  border-radius: 16px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  color: #fff;
}
.advantage-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--gray-900);
}
.advantage-card p {
  font-size: 14px;
  color: var(--gray-500);
  line-height: 1.7;
}

/* ====== 关于我们 ====== */
.about-section {
  background: var(--gray-50);
}
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.about-text h2 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 24px;
  color: var(--gray-900);
}
.about-text p {
  font-size: 16px;
  color: var(--gray-600);
  line-height: 1.8;
  margin-bottom: 16px;
}
.about-image {
  height: 400px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--gray-200), var(--gray-300));
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}
.about-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.about-image .placeholder {
  font-size: 80px;
  color: var(--gray-400);
}

/* ====== 联系我们 ====== */
.contact-section {
  background: var(--gray-900);
  color: #fff;
}
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
}
.contact-info h2 {
  font-size: 32px;
  margin-bottom: 24px;
}
.contact-info p {
  color: rgba(255,255,255,.7);
  margin-bottom: 32px;
  font-size: 16px;
}
.contact-list { display: flex; flex-direction: column; gap: 20px; }
.contact-list li {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}
.contact-list .icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(14,165,233,.15);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  color: var(--accent-light);
  flex-shrink: 0;
}
.contact-list .label { font-size: 13px; color: rgba(255,255,255,.5); }
.contact-list .value { font-size: 16px; color: #fff; font-weight: 500; }

.contact-form {
  background: rgba(255,255,255,.05);
  border: 1px solid rgba(255,255,255,.1);
  border-radius: var(--radius-lg);
  padding: 40px;
}
.contact-form h3 {
  font-size: 24px;
  margin-bottom: 24px;
}
.contact-form .form-group {
  margin-bottom: 20px;
}
.contact-form label {
  display: block;
  font-size: 14px;
  color: rgba(255,255,255,.7);
  margin-bottom: 8px;
}
.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 12px 16px;
  background: rgba(255,255,255,.05);
  border: 1px solid rgba(255,255,255,.15);
  border-radius: var(--radius);
  color: #fff;
  font-size: 15px;
  font-family: inherit;
  transition: var(--transition);
}
.contact-form input::placeholder,
.contact-form textarea::placeholder {
  color: rgba(255,255,255,.3);
}
.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--accent);
  background: rgba(255,255,255,.08);
}
.contact-form textarea { resize: vertical; min-height: 120px; }

/* ====== Footer ====== */
.footer {
  background: #0a0e1a;
  color: rgba(255,255,255,.5);
  padding: 48px 0 24px;
  font-size: 14px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 32px;
}
.footer-brand h3 {
  color: #fff;
  font-size: 20px;
  margin-bottom: 16px;
}
.footer-brand p { line-height: 1.7; }
.footer-col h4 {
  color: #fff;
  font-size: 16px;
  margin-bottom: 16px;
}
.footer-col ul { display: flex; flex-direction: column; gap: 10px; }
.footer-col a:hover { color: var(--accent-light); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding-top: 24px;
  text-align: center;
  font-size: 13px;
}

/* ====== 页面标题 ====== */
.page-banner {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  padding: 60px 0;
  text-align: center;
}
.page-banner h1 {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 12px;
}
.page-banner p {
  font-size: 16px;
  color: rgba(255,255,255,.7);
}
.breadcrumb {
  display: flex;
  justify-content: center;
  gap: 8px;
  font-size: 14px;
  margin-top: 16px;
}
.breadcrumb a { color: rgba(255,255,255,.6); }
.breadcrumb a:hover { color: #fff; }
.breadcrumb span { color: rgba(255,255,255,.4); }

/* ====== 产品详情 ====== */
.product-detail {
  padding: 60px 0;
}
.product-detail-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
}
.product-gallery {
  position: relative;
}
.product-gallery-main {
  height: 440px;
  border-radius: var(--radius-lg);
  background: var(--gray-100);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}
.product-gallery-main img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.product-gallery-main .placeholder {
  font-size: 80px;
  color: var(--gray-300);
}
.product-gallery-thumbs {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.product-gallery-thumbs img {
  width: 80px;
  height: 80px;
  border-radius: var(--radius);
  object-fit: cover;
  cursor: pointer;
  border: 2px solid transparent;
  transition: var(--transition);
}
.product-gallery-thumbs img.active,
.product-gallery-thumbs img:hover {
  border-color: var(--accent);
}
.product-info h1 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--gray-900);
}
.product-info .product-category {
  display: inline-block;
  padding: 4px 12px;
  background: var(--accent);
  color: #fff;
  border-radius: 50px;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 20px;
}
.product-info .product-desc {
  font-size: 16px;
  color: var(--gray-600);
  line-height: 1.8;
  margin-bottom: 24px;
}
.product-features-list {
  margin-bottom: 32px;
}
.product-features-list h3 {
  font-size: 18px;
  margin-bottom: 16px;
  color: var(--gray-900);
}
.product-features-list ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.product-features-list li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 15px;
  color: var(--gray-700);
}
.product-features-list li i {
  color: var(--green);
}

/* ====== 响应式 ====== */
@media (max-width: 1024px) {
  .stats-grid, .advantages-grid { grid-template-columns: repeat(2, 1fr); }
  .about-grid, .contact-grid, .product-detail-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: #fff;
    flex-direction: column;
    padding: 16px;
    box-shadow: var(--shadow-lg);
  }
  .nav-menu.show { display: flex; }
  .nav-toggle { display: block; }
  .hero h1 { font-size: 32px; }
  .hero .subtitle { font-size: 16px; }
  .section { padding: 48px 0; }
  .section-header h2 { font-size: 28px; }
  .stats-grid, .advantages-grid { grid-template-columns: 1fr; }
  .products-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .topbar-info { flex-direction: column; gap: 4px; font-size: 12px; }
  .contact-form { padding: 24px; }
}