/* ===== Reset & Base ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  color: #1a1a1a;
  line-height: 1.6;
  background: #fff;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

/* ===== Variables ===== */
:root {
  --primary: #0a3d62;        /* 深蓝 */
  --primary-light: #1e5a8e;
  --accent: #ff8c00;         /* 橙色点缀 */
  --steel: #5a6772;          /* 钢铁灰 */
  --bg-light: #f4f6f8;
  --border: #e1e6ea;
  --text: #1a1a1a;
  --text-muted: #6b7280;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-hover: 0 8px 30px rgba(0,0,0,0.15);
}

/* ===== Layout ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== Navbar ===== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.98);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow 0.3s;
}
.navbar.scrolled { box-shadow: var(--shadow); }
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 22px;
  color: var(--primary);
  letter-spacing: -0.3px;
}
.logo-icon {
  width: 38px; height: 38px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 900;
  font-size: 18px;
}
.nav-links {
  display: flex;
  gap: 35px;
}
.nav-links a {
  font-weight: 500;
  color: var(--text);
  position: relative;
  transition: color 0.2s;
}
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: -22px; left: 0; right: 0;
  height: 3px;
  background: var(--accent);
}
.nav-cta {
  background: var(--primary);
  color: white !important;
  padding: 10px 22px;
  border-radius: 6px;
  font-weight: 600;
  transition: background 0.2s, transform 0.2s;
}
.nav-cta:hover { background: var(--primary-light); transform: translateY(-1px); }
.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--primary);
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 580px;
  display: flex;
  align-items: center;
  color: white;
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(10,61,98,0.92), rgba(30,90,142,0.85)),
    url('https://images.unsplash.com/photo-1581094794329-c8112a89af12?w=1600') center/cover;
}
.hero-content { max-width: 720px; padding: 80px 0; }
.hero-tag {
  display: inline-block;
  padding: 6px 14px;
  background: rgba(255,140,0,0.2);
  color: #ffb766;
  border: 1px solid rgba(255,140,0,0.4);
  border-radius: 4px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 1px;
  margin-bottom: 20px;
  text-transform: uppercase;
}
.hero h1 {
  font-size: 52px;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
  letter-spacing: -1px;
}
.hero h1 .accent { color: #ffb766; }
.hero p {
  font-size: 18px;
  margin-bottom: 35px;
  color: rgba(255,255,255,0.9);
  max-width: 600px;
}
.hero-buttons { display: flex; gap: 15px; flex-wrap: wrap; }
.btn {
  display: inline-block;
  padding: 14px 32px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 15px;
  transition: all 0.25s;
  cursor: pointer;
  border: none;
  text-align: center;
}
.btn-primary {
  background: var(--accent);
  color: white;
}
.btn-primary:hover {
  background: #ff7a00;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(255,140,0,0.4);
}
.btn-outline {
  background: transparent;
  color: white;
  border: 2px solid rgba(255,255,255,0.5);
}
.btn-outline:hover {
  background: white;
  color: var(--primary);
  border-color: white;
}

/* ===== Section ===== */
.section {
  padding: 80px 0;
}
.section-light { background: var(--bg-light); }
.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 50px;
}
.section-tag {
  display: inline-block;
  color: var(--accent);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 12px;
}
.section h2 {
  font-size: 38px;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 15px;
  letter-spacing: -0.5px;
}
.section-header p {
  color: var(--text-muted);
  font-size: 17px;
}

/* ===== Features Grid ===== */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 25px;
}
.feature-card {
  background: white;
  padding: 35px 28px;
  border-radius: 10px;
  border: 1px solid var(--border);
  transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}
.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: var(--primary);
}
.feature-icon {
  width: 60px; height: 60px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 26px;
  margin-bottom: 20px;
}
.feature-card h3 {
  font-size: 19px;
  color: var(--primary);
  margin-bottom: 10px;
  font-weight: 700;
}
.feature-card p {
  color: var(--text-muted);
  font-size: 15px;
}

/* ===== Product Cards ===== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 25px;
}
.product-card {
  background: white;
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid var(--border);
  transition: all 0.3s;
  display: flex;
  flex-direction: column;
}
.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
  border-color: var(--primary-light);
}
.product-image {
  height: 200px;
  background: linear-gradient(135deg, #e8eef3, #c8d5e0);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 60px;
  color: var(--steel);
  position: relative;
}
.product-badge {
  position: absolute;
  top: 12px; right: 12px;
  background: var(--accent);
  color: white;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.5px;
}
.product-body { padding: 22px; flex: 1; display: flex; flex-direction: column; }
.product-body h3 {
  font-size: 17px;
  color: var(--primary);
  margin-bottom: 8px;
  font-weight: 700;
}
.product-model {
  color: var(--text-muted);
  font-size: 13px;
  margin-bottom: 12px;
  font-family: 'Courier New', monospace;
}
.product-desc {
  color: var(--text-muted);
  font-size: 14px;
  margin-bottom: 18px;
  flex: 1;
}
.product-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 15px;
  border-top: 1px solid var(--border);
}
.product-price {
  font-size: 20px;
  font-weight: 700;
  color: var(--accent);
}
.product-price .label {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 500;
  display: block;
}
.product-inquire {
  background: var(--primary);
  color: white;
  padding: 8px 16px;
  border-radius: 5px;
  font-size: 13px;
  font-weight: 600;
  transition: background 0.2s;
}
.product-inquire:hover { background: var(--primary-light); }

/* ===== Category Filter ===== */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin-bottom: 40px;
}
.filter-btn {
  padding: 9px 20px;
  background: white;
  border: 1px solid var(--border);
  border-radius: 30px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: all 0.2s;
}
.filter-btn:hover { border-color: var(--primary); color: var(--primary); }
.filter-btn.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

/* ===== About Page ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.about-image {
  height: 380px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 100px;
  box-shadow: var(--shadow);
}
.about-content h2 { text-align: left; }
.about-content > p { margin-bottom: 20px; color: var(--text); font-size: 16px; }
.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 30px;
  padding-top: 30px;
  border-top: 1px solid var(--border);
}
.stat-item { text-align: center; }
.stat-num {
  font-size: 34px;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
}
.stat-label {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 5px;
}

/* ===== Process Steps ===== */
.process {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 25px;
  position: relative;
}
.process-step {
  text-align: center;
  position: relative;
  padding: 20px;
}
.process-num {
  width: 60px; height: 60px;
  background: white;
  border: 3px solid var(--accent);
  color: var(--accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: 800;
  margin: 0 auto 18px;
}
.process-step h4 {
  color: var(--primary);
  font-size: 17px;
  margin-bottom: 8px;
}
.process-step p { color: var(--text-muted); font-size: 14px; }

/* ===== Contact Page ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: 50px;
}
.contact-info { padding: 20px 0; }
.contact-info h2 { text-align: left; }
.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  margin: 25px 0;
}
.contact-icon {
  width: 50px; height: 50px;
  flex-shrink: 0;
  background: var(--bg-light);
  color: var(--primary);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
}
.contact-item h4 {
  color: var(--primary);
  font-size: 15px;
  margin-bottom: 4px;
  font-weight: 700;
}
.contact-item p { color: var(--text-muted); font-size: 15px; }
.contact-form {
  background: white;
  padding: 40px;
  border-radius: 12px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}
.contact-form h3 {
  color: var(--primary);
  margin-bottom: 25px;
  font-size: 24px;
}
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 15px;
}
.form-group { margin-bottom: 18px; }
.form-group label {
  display: block;
  margin-bottom: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
}
.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
  font-family: inherit;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(10,61,98,0.1);
}
.form-group textarea { resize: vertical; min-height: 110px; }
.form-submit {
  background: var(--accent);
  color: white;
  padding: 14px 32px;
  border-radius: 6px;
  font-size: 15px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  width: 100%;
  transition: background 0.2s, transform 0.2s;
}
.form-submit:hover {
  background: #ff7a00;
  transform: translateY(-1px);
}
.form-submit:disabled {
  background: var(--text-muted);
  cursor: not-allowed;
  transform: none;
}
.form-message {
  padding: 12px;
  border-radius: 6px;
  margin-top: 15px;
  font-size: 14px;
  display: none;
}
.form-message.success {
  background: #d4f5e6;
  color: #1a7a4a;
  display: block;
}
.form-message.error {
  background: #fde0e0;
  color: #c0392b;
  display: block;
}

/* ===== CTA Banner ===== */
.cta-banner {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  text-align: center;
  padding: 70px 20px;
}
.cta-banner h2 {
  color: white;
  font-size: 32px;
  margin-bottom: 12px;
}
.cta-banner p {
  font-size: 17px;
  opacity: 0.9;
  margin-bottom: 25px;
}

/* ===== Footer ===== */
.footer {
  background: #0a1f33;
  color: rgba(255,255,255,0.7);
  padding: 60px 0 25px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer h4 {
  color: white;
  font-size: 15px;
  margin-bottom: 18px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
}
.footer-about p {
  font-size: 14px;
  line-height: 1.7;
  margin: 15px 0;
}
.footer ul li { margin-bottom: 10px; font-size: 14px; }
.footer ul li a { transition: color 0.2s; }
.footer ul li a:hover { color: var(--accent); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 25px;
  text-align: center;
  font-size: 13px;
  color: rgba(255,255,255,0.5);
}
.footer-bottom .legal-name { color: rgba(255,255,255,0.7); }

/* ===== Animations ===== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .hero h1 { font-size: 38px; }
  .section h2 { font-size: 30px; }
  .about-grid, .contact-grid { grid-template-columns: 1fr; gap: 35px; }
  .about-image { height: 280px; font-size: 80px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .menu-toggle { display: block; }
  .nav-links {
    position: absolute;
    top: 70px; left: 0; right: 0;
    background: white;
    flex-direction: column;
    gap: 0;
    padding: 20px;
    box-shadow: var(--shadow);
    transform: translateY(-200%);
    transition: transform 0.3s;
  }
  .nav-links.open { transform: translateY(0); }
  .nav-links a { padding: 12px 0; border-bottom: 1px solid var(--border); }
  .nav-links a.active::after { display: none; }
  .nav-cta { margin-top: 10px; text-align: center; }
  .hero { min-height: 480px; }
  .hero h1 { font-size: 32px; }
  .hero p { font-size: 16px; }
  .section { padding: 60px 0; }
  .section h2 { font-size: 26px; }
  .form-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .contact-form { padding: 25px; }
}