/* ===== Reset & base ===== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: 'Inter', 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', Arial, sans-serif;
  color: #1a2332;
  background: #ffffff;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
html[lang="zh"] body {
  font-family: 'Noto Sans SC', 'Inter', system-ui, -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; }

:root {
  --primary: #0a3d62;
  --primary-dark: #062c47;
  --accent: #d97706;
  --accent-light: #f59e0b;
  --bg: #ffffff;
  --bg-alt: #f6f8fb;
  --bg-dark: #0d1b2a;
  --text: #1a2332;
  --text-muted: #5a6878;
  --border: #e3e8ef;
  --shadow-sm: 0 1px 3px rgba(10, 30, 60, 0.06), 0 1px 2px rgba(10, 30, 60, 0.04);
  --shadow-md: 0 8px 24px rgba(10, 30, 60, 0.08), 0 2px 6px rgba(10, 30, 60, 0.04);
  --shadow-lg: 0 24px 60px rgba(10, 30, 60, 0.12);
  --radius: 10px;
  --radius-lg: 16px;
  --maxw: 1200px;
}

.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

h1, h2, h3, h4 { color: var(--text); margin: 0 0 0.6em; line-height: 1.25; font-weight: 700; letter-spacing: -0.01em; }
h1 { font-size: clamp(2rem, 4.5vw, 3.5rem); font-weight: 800; }
h2 { font-size: clamp(1.6rem, 3vw, 2.25rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; color: var(--text-muted); }

.eyebrow, .section-eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}

.section-head { text-align: center; max-width: 720px; margin: 0 auto 56px; }
.section-head p { font-size: 1.05rem; }

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 26px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  border: 2px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 14px rgba(217, 119, 6, 0.32);
}
.btn-primary:hover { background: var(--accent-light); transform: translateY(-1px); }
.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.4);
}
.btn-ghost:hover { background: rgba(255, 255, 255, 0.1); border-color: rgba(255, 255, 255, 0.7); }

/* ===== Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.site-header.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-sm);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
  gap: 24px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--primary);
}
.brand-mark {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
}
.brand-mark img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: contain;
}
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-cn { font-size: 1.15rem; font-weight: 700; color: var(--primary); }
.brand-en { font-size: 0.65rem; font-weight: 600; letter-spacing: 0.1em; color: var(--text-muted); margin-top: 2px; }

.site-nav { display: flex; gap: 36px; }
.site-nav a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text);
  position: relative;
  transition: color 0.2s ease;
}
.site-nav a::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -6px;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 0.2s ease;
}
.site-nav a:hover { color: var(--primary); }
.site-nav a:hover::after { transform: scaleX(1); }

.header-actions { display: flex; align-items: center; gap: 12px; }
.lang-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
}
.lang-opt { padding: 2px 6px; border-radius: 4px; transition: color 0.2s ease, background 0.2s ease; }
.lang-opt.active { color: var(--primary); background: #fff; box-shadow: var(--shadow-sm); }
.lang-sep { color: var(--border); }

.mobile-toggle { display: none; background: none; border: none; padding: 8px; }
.mobile-toggle span { display: block; width: 22px; height: 2px; background: var(--text); margin: 4px 0; transition: 0.2s ease; }

/* ===== Hero ===== */
.hero {
  position: relative;
  color: #fff;
  padding: 120px 0 100px;
  overflow: hidden;
  background: var(--bg-dark);
}
.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at top right, rgba(217, 119, 6, 0.18), transparent 55%),
    radial-gradient(ellipse at bottom left, rgba(10, 61, 98, 0.55), transparent 55%),
    linear-gradient(135deg, #0d1b2a 0%, #1b2a3d 50%, #0a3d62 100%);
}
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
  background-size: 50px 50px;
  mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
}
.hero-content { position: relative; max-width: 820px; }
.hero .eyebrow { color: var(--accent-light); }
.hero h1 { color: #fff; margin-bottom: 24px; }
.hero-sub { font-size: 1.15rem; color: rgba(255, 255, 255, 0.78); max-width: 600px; margin-bottom: 36px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: 64px; }
.hero-stats { display: flex; gap: 56px; flex-wrap: wrap; }
.stat { display: flex; flex-direction: column; }
.stat-num { font-size: 2.25rem; font-weight: 800; color: #fff; letter-spacing: -0.02em; }
.stat-label { font-size: 0.85rem; color: rgba(255, 255, 255, 0.6); letter-spacing: 0.05em; text-transform: uppercase; }

/* ===== About ===== */
.about { padding: 100px 0; background: var(--bg); }
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}
.about-points { list-style: none; padding: 0; margin: 32px 0 0; }
.about-points li {
  padding: 18px 0;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.about-points li:last-child { border-bottom: 1px solid var(--border); }
.about-points strong { font-weight: 600; color: var(--primary); }
.about-points span { color: var(--text-muted); font-size: 0.95rem; }

.about-visual {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 16px;
  height: 480px;
}
.visual-card {
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, #2a3f5f 0%, #0a3d62 100%);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.visual-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(45deg, transparent 0, transparent 8px, rgba(255,255,255,0.04) 8px, rgba(255,255,255,0.04) 9px);
}
.visual-card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 30% 30%, rgba(217, 119, 6, 0.25), transparent 60%);
}
.v1 { grid-row: span 2; }
.v2 { background: linear-gradient(135deg, #d97706 0%, #b45309 100%); }
.v3 { background: linear-gradient(135deg, #0a3d62 0%, #1b2a3d 100%); }

/* ===== Showcase (video) ===== */
.showcase {
  padding: 100px 0;
  background: linear-gradient(180deg, #ffffff 0%, var(--bg-alt) 100%);
}
.video-wrap {
  position: relative;
  max-width: 980px;
  margin: 0 auto;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  background: #0d1b2a;
  aspect-ratio: 16 / 9;
}
.video-wrap video {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
  background: #0d1b2a;
}

/* ===== Products ===== */
.products { padding: 100px 0; background: var(--bg-alt); }
.product-tabs {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin-bottom: 40px;
  padding: 6px;
  background: #fff;
  border-radius: 999px;
  box-shadow: var(--shadow-sm);
  width: fit-content;
  margin-left: auto;
  margin-right: auto;
  max-width: 100%;
}
.tab {
  padding: 10px 20px;
  border-radius: 999px;
  border: none;
  background: transparent;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-muted);
  transition: background 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}
.tab:hover { color: var(--primary); }
.tab.active {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 4px 12px rgba(10, 61, 98, 0.25);
}

.panel { display: none; animation: fadeIn 0.3s ease; }
.panel.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

.panel-head {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 48px;
  align-items: center;
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 40px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
}
.panel-image {
  aspect-ratio: 4 / 3;
  border-radius: var(--radius);
  background: linear-gradient(135deg, #f0f4f9 0%, #d8e0eb 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}
.panel-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.4s ease;
}
.panel-image:hover img { transform: scale(1.03); }
.panel-image img.img-fallback {
  /* Hide broken image — gradient background and "photo coming soon" pseudo-element show through */
  visibility: hidden;
}
.panel-image:has(img.img-fallback)::after {
  content: 'Product photo coming soon';
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  opacity: 0.7;
}
html[lang="zh"] .panel-image:has(img.img-fallback)::after { content: '产品图片即将上线'; }
.panel-info h3 {
  font-size: 1.6rem;
  color: var(--primary);
  margin-bottom: 12px;
}
.panel-info .panel-tag {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  background: rgba(217, 119, 6, 0.1);
  padding: 5px 10px;
  border-radius: 999px;
  margin-bottom: 14px;
}
.panel-features {
  list-style: none;
  padding: 0;
  margin: 18px 0 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}
.panel-features li {
  font-size: 0.92rem;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 8px;
}
.panel-features li::before {
  content: '';
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
}

.spec-table-wrap {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  overflow-x: auto;
}
.spec-table-wrap h4 {
  margin: 0 0 20px;
  font-size: 1rem;
  color: var(--primary);
  letter-spacing: 0.02em;
}
.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  min-width: 480px;
}
.spec-table th, .spec-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.spec-table th {
  background: var(--bg-alt);
  font-weight: 600;
  color: var(--primary);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.spec-table tbody tr:hover { background: rgba(10, 61, 98, 0.025); }
.spec-table td.muted { color: var(--text-muted); }
.spec-note { font-size: 0.82rem; color: var(--text-muted); margin-top: 14px; }

/* ===== Capabilities ===== */
.capabilities { padding: 100px 0; background: var(--bg); }
.cap-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.cap-card {
  background: var(--bg-alt);
  border-radius: var(--radius-lg);
  padding: 32px;
  border: 1px solid var(--border);
  transition: transform 0.2s ease, box-shadow 0.25s ease, border-color 0.2s ease;
}
.cap-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}
.cap-icon {
  width: 56px; height: 56px;
  border-radius: 12px;
  background: #fff;
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 18px;
  color: var(--accent);
  box-shadow: var(--shadow-sm);
}
.cap-icon svg { width: 28px; height: 28px; }
.cap-card h3 { color: var(--primary); margin-bottom: 8px; }
.cap-card p { font-size: 0.92rem; margin: 0; }

/* ===== Contact ===== */
.contact { padding: 100px 0; background: var(--bg-alt); }
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 64px;
  align-items: start;
}
.contact-list { list-style: none; padding: 0; margin: 32px 0 0; display: grid; gap: 22px; }
.contact-list li { display: flex; gap: 16px; align-items: flex-start; }
.contact-icon {
  width: 44px; height: 44px;
  flex-shrink: 0;
  border-radius: 10px;
  background: #fff;
  border: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  color: var(--primary);
}
.contact-icon svg { width: 20px; height: 20px; }
.contact-list .contact-label {
  display: block;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 2px;
}
.contact-list a, .contact-list span { color: var(--text); font-weight: 500; }
.contact-list a:hover { color: var(--accent); }

.contact-form {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 18px;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.contact-form label { display: flex; flex-direction: column; gap: 6px; font-size: 0.85rem; font-weight: 600; color: var(--text); }
.contact-form input,
.contact-form select,
.contact-form textarea {
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.95rem;
  font-family: inherit;
  font-weight: 400;
  color: var(--text);
  background: #fff;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(10, 61, 98, 0.12);
}
.contact-form textarea { resize: vertical; min-height: 100px; }
.contact-form .btn { align-self: flex-start; margin-top: 6px; }
.form-status { margin: 0; font-size: 0.9rem; min-height: 1.2em; }
.form-status.success { color: #15803d; }
.form-status.error { color: #b91c1c; }

/* ===== Footer ===== */
.site-footer { background: var(--bg-dark); color: rgba(255, 255, 255, 0.78); padding: 64px 0 0; }
.footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr;
  gap: 48px;
  padding-bottom: 48px;
}
.footer-brand .brand-cn { color: #fff; font-size: 1.25rem; }
.footer-brand .brand-en { color: rgba(255, 255, 255, 0.5); display: block; margin: 4px 0 14px; }
.footer-brand p { color: rgba(255, 255, 255, 0.6); font-size: 0.92rem; max-width: 320px; }
.footer-links { display: flex; flex-direction: column; gap: 10px; }
.footer-links h4 { color: #fff; font-size: 0.95rem; margin-bottom: 10px; }
.footer-links a, .footer-links span { color: rgba(255, 255, 255, 0.65); font-size: 0.9rem; transition: color 0.2s ease; }
.footer-links a:hover { color: var(--accent-light); }
.footer-bottom { border-top: 1px solid rgba(255, 255, 255, 0.1); padding: 22px 0; }
.footer-bottom .container { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; font-size: 0.82rem; color: rgba(255, 255, 255, 0.5); }

/* ===== Responsive ===== */
@media (max-width: 960px) {
  .site-nav {
    position: absolute;
    top: 76px; left: 0; right: 0;
    background: #fff;
    flex-direction: column;
    padding: 20px 24px;
    gap: 6px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    transform: translateY(-200%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.25s ease, opacity 0.25s ease;
  }
  .site-nav.open { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .site-nav a { padding: 10px 0; }
  .mobile-toggle { display: block; }

  .about-grid, .contact-grid { grid-template-columns: 1fr; gap: 48px; }
  .about-visual { height: 360px; }
  .panel-head { grid-template-columns: 1fr; padding: 28px; gap: 24px; }
  .cap-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-inner { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 600px) {
  .container { padding: 0 18px; }
  .hero { padding: 80px 0 64px; }
  .hero-stats { gap: 28px; }
  .stat-num { font-size: 1.7rem; }
  .about, .products, .capabilities, .contact { padding: 64px 0; }
  .panel-features { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .cap-grid { grid-template-columns: 1fr; }
  .brand-en { display: none; }
  .header-inner { gap: 12px; }
}