:root {
  --primary: #014DB2;
  --primary-dark: #001645;
  --accent: #F59E0B;
  --accent-light: #FCD34D;
  --bg: #F9F9F9;
  --card-bg: #FFFFFF;
  --text: #0A1628;
  --text-secondary: #6B7280;
  --text-muted: #9CA3AF;
  --border: #EAEAEA;
  --border-strong: #D6D9DE;
  --dark-bg: #0A1628;
  --dark-card: rgba(255,255,255,0.04);
  --dark-border: rgba(255,255,255,0.08);
  --radius: 0;
  --shadow: none;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: "Noto Sans SC", "IBM Plex Sans", -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 16px;
}

a { text-decoration: none; color: inherit; transition: color 0.2s; }

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

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* Top Bar */
.topbar { background: var(--dark-bg); color: var(--text-muted); font-size: 13px; padding: 8px 0; }
.topbar .container { display: flex; justify-content: space-between; align-items: center; }
.topbar-left, .topbar-right { display: flex; align-items: center; gap: 20px; }
.topbar a { color: var(--text-muted); }
.topbar a:hover { color: #fff; }

/* Header */
.header { background: var(--card-bg); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 100; }
.header .container { display: flex; justify-content: space-between; align-items: center; height: 72px; }
.logo { display: flex; align-items: center; gap: 10px; }
.logo-mark { width: 36px; height: 36px; background: var(--primary); display: flex; align-items: center; justify-content: center; color: #fff; font-weight: 700; font-size: 18px; }
.logo-text { display: flex; flex-direction: column; line-height: 1.2; }
.logo-cn { font-size: 16px; font-weight: 700; color: var(--text); }
.logo-en { font-size: 9px; color: var(--text-secondary); letter-spacing: 2px; font-family: "Space Grotesk", sans-serif; }

.nav { display: flex; gap: 36px; }
.nav a { font-size: 15px; color: var(--text); position: relative; }
.nav a:hover, .nav a.active { color: var(--primary); }
.nav a.active::after { content: ''; position: absolute; bottom: -24px; left: 0; width: 100%; height: 2px; background: var(--primary); }

.btn { display: inline-flex; align-items: center; gap: 6px; padding: 10px 24px; font-size: 14px; font-weight: 600; border: none; cursor: pointer; transition: all 0.2s; font-family: inherit; }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: #D97706; }
.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }
.btn-outline-light { background: rgba(255,255,255,0.1); border: 1px solid rgba(255,255,255,0.4); color: #fff; }
.btn-outline-light:hover { background: rgba(255,255,255,0.2); }

.mobile-menu-btn { display: none; flex-direction: column; gap: 5px; cursor: pointer; }
.mobile-menu-btn span { display: block; width: 24px; height: 2px; background: var(--text); }

/* Hero */
.hero { position: relative; min-height: 640px; display: flex; flex-direction: column; overflow: hidden; background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%); }
.hero-bg { position: absolute; inset: 0; background-size: cover; background-position: center; opacity: 0.35; }
.hero-overlay { position: absolute; inset: 0; background: linear-gradient(90deg, rgba(0,22,69,0.85) 0%, rgba(1,77,178,0.5) 100%); }
.hero > .container { position: relative; z-index: 2; flex: 1; display: flex; align-items: center; }
.hero-content { max-width: 720px; }
.hero-tag { display: inline-flex; align-items: center; gap: 8px; background: rgba(245,158,11,0.15); padding: 6px 16px; margin-bottom: 24px; }
.hero-tag-dot { width: 6px; height: 6px; background: var(--accent); }
.hero-tag span { color: var(--accent-light); font-size: 13px; }
.hero h1 { font-size: 52px; line-height: 1.2; color: #fff; font-weight: 700; margin-bottom: 20px; }
.hero p { font-size: 17px; color: #9DB4D1; margin-bottom: 28px; line-height: 1.7; }
.hero-btns { display: flex; gap: 16px; }

.hero-stats { position: relative; z-index: 3; width: 100%; padding-bottom: 56px; }
.hero-stats-inner { display: flex; align-items: stretch; background: #fff; border: 1px solid var(--border); }
.stat-item { flex: 1; padding: 24px 16px; text-align: center; border-right: 1px solid var(--border); display: flex; flex-direction: column; justify-content: center; align-items: center; gap: 8px; }
.stat-item:last-child { border-right: none; }
.stat-num { font-size: 28px; font-weight: 700; color: var(--primary); font-family: "Space Grotesk", sans-serif; }
.stat-label { font-size: 13px; color: var(--text-secondary); }

/* Section Common */
.section { padding: 80px 0; }
.section-head { text-align: center; margin-bottom: 48px; }
.section-label { font-size: 13px; color: var(--accent); letter-spacing: 3px; font-weight: 600; font-family: "Space Grotesk", sans-serif; text-transform: uppercase; margin-bottom: 12px; }
.section-title { font-size: 36px; font-weight: 700; color: var(--text); margin-bottom: 12px; }
.section-desc { font-size: 15px; color: var(--text-secondary); }

/* Products */
.product-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.product-card { display: block; background: var(--card-bg); border: 1px solid var(--border); transition: transform 0.2s, box-shadow 0.2s; text-decoration: none; color: inherit; }
.product-card:hover { transform: translateY(-4px); box-shadow: 0 12px 40px rgba(1,77,178,0.08); }
.product-img { height: 200px; background: #1E3A5F; overflow: hidden; }
.product-img img { width: 100%; height: 100%; object-fit: cover; }
.product-body { padding: 24px; }
.product-body h3 { font-size: 20px; font-weight: 700; margin-bottom: 10px; }
.product-body p { font-size: 14px; color: var(--text-secondary); line-height: 1.6; margin-bottom: 16px; }
.product-link { display: inline-flex; align-items: center; gap: 6px; font-size: 13px; font-weight: 600; color: var(--primary); }

/* Advantages */
.advantages { background: var(--dark-bg); color: #fff; }
.advantages .section-title { color: #fff; }
.advantages .section-desc { color: #9DB4D1; }
.adv-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.adv-card { background: var(--dark-card); border: 1px solid var(--dark-border); padding: 32px; }
.adv-icon { width: 48px; height: 48px; background: var(--accent); display: flex; align-items: center; justify-content: center; margin-bottom: 16px; }
.adv-icon svg { width: 24px; height: 24px; stroke: #fff; }
.adv-card h3 { font-size: 20px; font-weight: 700; margin-bottom: 10px; }
.adv-card p { font-size: 14px; color: #9DB4D1; line-height: 1.6; }

/* Applications */
.app-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; }
.app-card { height: 180px; padding: 24px; display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; color: #fff; }
.app-card:nth-child(odd) { background: var(--primary); }
.app-card:nth-child(even) { background: var(--dark-bg); }
.app-card h3 { font-size: 16px; font-weight: 700; margin-bottom: 8px; }
.app-card p { font-size: 12px; color: #9DB4D1; line-height: 1.5; }

/* About & News */
.about-news { background: #fff; }
.about-news .container { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.about-col h2 { font-size: 28px; margin-bottom: 8px; }
.about-line { width: 48px; height: 3px; background: var(--primary); margin: 16px 0 20px; }
.about-col p { font-size: 14px; color: var(--text-secondary); line-height: 1.8; margin-bottom: 16px; }

.news-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.news-head h2 { font-size: 28px; }
.news-more { font-size: 13px; color: var(--primary); font-weight: 500; }
.news-item { display: flex; gap: 16px; padding: 16px 0; border-bottom: 1px solid var(--border); }
.news-date { width: 60px; text-align: center; }
.news-date .day { font-size: 24px; font-weight: 700; color: var(--primary); font-family: "Space Grotesk", sans-serif; }
.news-date .month { font-size: 11px; color: var(--text-muted); }
.news-body h4 { font-size: 15px; font-weight: 600; margin-bottom: 4px; }
.news-body p { font-size: 13px; color: var(--text-muted); }

/* CTA */
.cta { background: var(--primary); color: #fff; padding: 56px 0; }
.cta .container { display: flex; justify-content: space-between; align-items: center; }
.cta h2 { font-size: 28px; margin-bottom: 4px; }
.cta p { color: #9DB4D1; }
.cta-btns { display: flex; gap: 16px; }

/* Footer */
.footer { background: var(--dark-bg); color: #fff; padding: 56px 0 24px; }
.footer-top { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.2fr; gap: 48px; margin-bottom: 40px; }
.footer-brand p { font-size: 13px; color: var(--text-muted); line-height: 1.8; margin-top: 16px; }
.footer-col h4 { font-size: 14px; font-weight: 600; margin-bottom: 16px; }
.footer-col a { display: block; font-size: 13px; color: var(--text-muted); margin-bottom: 10px; }
.footer-col a:hover { color: #fff; }
.footer-col p { font-size: 13px; color: var(--text-muted); line-height: 1.8; margin-bottom: 6px; }
.footer-bottom { display: flex; justify-content: space-between; align-items: center; padding-top: 24px; border-top: 1px solid #1E2D3D; font-size: 12px; color: #4B5563; }

/* Page Header */
.page-header { background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%); color: #fff; padding: 80px 0 60px; text-align: center; }
.page-header h1 { font-size: 40px; margin-bottom: 12px; }
.page-header p { color: #9DB4D1; }

/* About Page */
.about-intro { background: #fff; }
.about-intro .container { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.about-intro h2 { font-size: 32px; margin-bottom: 20px; }
.about-intro p { color: var(--text-secondary); line-height: 1.8; margin-bottom: 16px; }
.about-image { background: #1E3A5F; min-height: 320px; display: flex; align-items: center; justify-content: center; color: #fff; }

.timeline { background: var(--bg); }
.timeline-item { display: flex; gap: 24px; margin-bottom: 24px; padding-left: 24px; border-left: 2px solid var(--primary); }
.timeline-year { font-size: 20px; font-weight: 700; color: var(--primary); font-family: "Space Grotesk", sans-serif; width: 120px; flex-shrink: 0; }

/* Products Page */
.product-detail { background: #fff; }
.product-detail-card { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; margin-bottom: 48px; padding-bottom: 48px; border-bottom: 1px solid var(--border); scroll-margin-top: 90px; }
.product-detail-card:last-child { border-bottom: none; margin-bottom: 0; padding-bottom: 0; }
.app-desc { font-size: 15px; line-height: 1.9; color: var(--text-secondary); margin-bottom: 18px; }
.app-label { display: block; font-size: 14px; font-weight: 700; color: var(--primary); margin-bottom: 12px; }
.app-parts { display: flex; flex-wrap: wrap; gap: 10px; }
.app-parts span { font-size: 13px; padding: 6px 12px; background: var(--bg-light); border: 1px solid var(--border); border-radius: 4px; color: var(--text-secondary); }
.product-info h3 { font-size: 28px; margin-bottom: 16px; }
.product-info p { color: var(--text-secondary); line-height: 1.8; margin-bottom: 16px; }
.product-specs { width: 100%; border-collapse: collapse; margin-top: 16px; }
.product-specs th, .product-specs td { text-align: left; padding: 12px 16px; border: 1px solid var(--border); font-size: 14px; }
.product-specs th { background: var(--bg); font-weight: 600; }

/* News Page */
.news-list { background: #fff; }
.news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.news-card { border: 1px solid var(--border); }
.news-card-img { height: 180px; background: var(--primary); display: flex; align-items: center; justify-content: center; color: #fff; }
.news-card-body { padding: 20px; }
.news-card-body .date { font-size: 12px; color: var(--text-muted); margin-bottom: 8px; }
.news-card-body h3 { font-size: 17px; font-weight: 600; margin-bottom: 8px; }
.news-card-body p { font-size: 14px; color: var(--text-secondary); line-height: 1.6; }

.news-detail { background: #fff; padding: 60px 0; }
.news-detail-inner { max-width: 800px; margin: 0 auto; }
.news-detail h1 { font-size: 32px; margin-bottom: 16px; }
.news-meta { color: var(--text-muted); font-size: 14px; margin-bottom: 32px; }
.news-detail-content { line-height: 1.8; color: var(--text-secondary); }
.news-detail-content p { margin-bottom: 16px; }

/* Contact Page */
.contact { background: #fff; }
.contact .container { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.contact-info h2 { font-size: 28px; margin-bottom: 20px; }
.contact-info p { color: var(--text-secondary); line-height: 1.8; margin-bottom: 16px; }
.contact-item { display: flex; gap: 12px; margin-bottom: 16px; }
.contact-item-icon { width: 40px; height: 40px; background: var(--bg); display: flex; align-items: center; justify-content: center; color: var(--primary); }
.contact-form { background: var(--bg); padding: 32px; }
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 14px; font-weight: 500; margin-bottom: 6px; }
.form-group input, .form-group textarea { width: 100%; padding: 12px 16px; border: 1px solid var(--border); font-family: inherit; font-size: 14px; background: #fff; }
.form-group input:focus, .form-group textarea:focus { outline: none; border-color: var(--primary); }
.form-group textarea { min-height: 120px; resize: vertical; }
.form-message { margin-top: 12px; font-size: 14px; }
.form-message.success { color: #10B981; }
.form-message.error { color: #EF4444; }

/* Admin */
.admin-body { font-family: "Noto Sans SC", -apple-system, sans-serif; background: #F3F4F6; }
.admin-login { min-height: 100vh; display: flex; align-items: center; justify-content: center; }
.admin-login-box { background: #fff; padding: 40px; width: 100%; max-width: 400px; border: 1px solid var(--border); }
.admin-login-box h1 { font-size: 24px; margin-bottom: 24px; text-align: center; }

.admin-layout { display: flex; min-height: 100vh; }
.admin-sidebar { width: 240px; background: var(--dark-bg); color: #fff; padding: 24px 0; position: fixed; height: 100vh; }
.admin-sidebar .logo { padding: 0 24px 24px; border-bottom: 1px solid rgba(255,255,255,0.08); margin-bottom: 16px; }
.admin-sidebar .logo span { color: #fff; }
.admin-nav a { display: block; padding: 14px 24px; color: #9CA3AF; font-size: 14px; }
.admin-nav a:hover, .admin-nav a.active { background: rgba(255,255,255,0.05); color: #fff; }
.admin-main { margin-left: 240px; flex: 1; padding: 32px; }
.admin-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 32px; }
.admin-header h1 { font-size: 24px; }
.admin-card { background: #fff; border: 1px solid var(--border); padding: 24px; margin-bottom: 24px; }
.admin-card h3 { font-size: 16px; margin-bottom: 16px; }
.admin-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-bottom: 24px; }
.admin-stat { background: #fff; border: 1px solid var(--border); padding: 20px; }
.admin-stat .num { font-size: 28px; font-weight: 700; color: var(--primary); }
.admin-stat .label { font-size: 13px; color: var(--text-secondary); }

.admin-table { width: 100%; border-collapse: collapse; font-size: 14px; }
.admin-table th, .admin-table td { text-align: left; padding: 12px; border-bottom: 1px solid var(--border); }
.admin-table th { background: var(--bg); font-weight: 600; }
.admin-table .badge { display: inline-block; padding: 2px 8px; font-size: 12px; border-radius: 2px; }
.badge-new { background: #FEE2E2; color: #991B1B; }
.badge-contacted { background: #DBEAFE; color: #1E40AF; }
.badge-closed { background: #D1FAE5; color: #065F46; }
.admin-btn { padding: 6px 12px; font-size: 13px; border: none; cursor: pointer; margin-right: 6px; }
.admin-btn-edit { background: var(--primary); color: #fff; }
.admin-btn-delete { background: #EF4444; color: #fff; }
.admin-btn-view { background: var(--bg); color: var(--text); border: 1px solid var(--border); }

.admin-form label { display: block; font-size: 14px; font-weight: 500; margin: 16px 0 6px; }
.admin-form input, .admin-form textarea, .admin-form select { width: 100%; padding: 10px 12px; border: 1px solid var(--border); font-family: inherit; font-size: 14px; }
.admin-form textarea { min-height: 200px; }
.admin-form .checkbox { width: auto; margin-right: 8px; }

/* Responsive */
@media (max-width: 1023px) {
  .product-grid, .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .app-grid { grid-template-columns: repeat(3, 1fr); }
  .news-grid { grid-template-columns: repeat(2, 1fr); }
  .about-news .container, .about-intro .container, .contact .container { grid-template-columns: 1fr; }
  .product-detail-card { display: flex; flex-direction: column; }
  .product-detail-card .about-image { order: -1; }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .cta .container { flex-direction: column; gap: 24px; text-align: center; }
}

@media (max-width: 767px) {
  .topbar .container { flex-direction: column; gap: 4px; font-size: 12px; }
  .nav { display: none; position: absolute; top: 72px; left: 0; right: 0; background: #fff; flex-direction: column; padding: 16px 20px; border-bottom: 1px solid var(--border); }
  .nav.open { display: flex; }
  .mobile-menu-btn { display: flex; }
  .header .btn { display: none; }
  .hero { height: auto; padding: 80px 0 40px; }
  .hero h1 { font-size: 32px; }
  .hero-stats-inner { flex-wrap: wrap; }
  .stat-item { flex: 1 1 50%; border-bottom: 1px solid var(--border); }
  .stat-item:nth-child(2n) { border-right: none; }
  .product-grid, .adv-grid, .app-grid, .news-grid { grid-template-columns: 1fr; }
  .section { padding: 48px 0; }
  .section-title { font-size: 28px; }
  .footer-top { grid-template-columns: 1fr 1fr; gap: 24px; }
  .product-detail-card .about-image { min-height: 200px; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
  .admin-sidebar { width: 100%; position: relative; height: auto; }
  .admin-main { margin-left: 0; }
  .admin-layout { flex-direction: column; }
  .admin-stats { grid-template-columns: repeat(2, 1fr); }
}