:root {
  --primary: #0f4c81;
  --primary-dark: #0a3560;
  --primary-light: #1a6bb5;
  --accent: #00b4d8;
  --accent-light: #48cae4;
  --text-dark: #1a1a2e;
  --text-mid: #4a4a5a;
  --text-light: #7a7a8a;
  --bg-white: #ffffff;
  --bg-light: #f5f7fa;
  --bg-dark: #0a1628;
  --border: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
  --radius: 8px;
  --radius-lg: 12px;
  --max-width: 1200px;
  --transition: 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  color: var(--text-dark);
  line-height: 1.6;
  background: var(--bg-white);
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

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

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

/* ========== NAV ========== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow var(--transition), background var(--transition);
}

.nav.scrolled {
  box-shadow: var(--shadow-sm);
  background: rgba(255,255,255,0.98);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 700;
  color: var(--primary);
}

.nav-logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 16px;
}

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-size: 15px;
  color: var(--text-mid);
  font-weight: 500;
  transition: color var(--transition);
  position: relative;
}

.nav-links a:hover {
  color: var(--primary);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width var(--transition);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 4px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-dark);
  transition: var(--transition);
}

/* ========== HERO ========== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 64px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scale(1.05);
  animation: heroZoom 20s ease-in-out infinite alternate;
}

@keyframes heroZoom {
  0% { transform: scale(1.05); }
  100% { transform: scale(1.12); }
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(10,22,40,0.92) 0%, rgba(10,53,96,0.85) 50%, rgba(15,76,129,0.78) 100%);
  z-index: 1;
}

.hero-particles {
  position: absolute;
  inset: 0;
  z-index: 2;
  overflow: hidden;
}

.particle {
  position: absolute;
  width: 4px;
  height: 4px;
  background: rgba(0, 180, 216, 0.4);
  border-radius: 50%;
  animation: particleFloat linear infinite;
}

@keyframes particleFloat {
  0% {
    transform: translateY(100vh) rotate(0deg);
    opacity: 0;
  }
  10% {
    opacity: 1;
  }
  90% {
    opacity: 1;
  }
  100% {
    transform: translateY(-100px) rotate(720deg);
    opacity: 0;
  }
}

.hero-content {
  position: relative;
  z-index: 3;
  max-width: 720px;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(0,180,216,0.15);
  border: 1px solid rgba(0,180,216,0.3);
  border-radius: 20px;
  color: var(--accent-light);
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 24px;
  letter-spacing: 0.5px;
}

.hero h1 {
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 800;
  color: #fff;
  line-height: 1.2;
  margin-bottom: 20px;
}

.hero h1 .highlight {
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 18px;
  color: rgba(255,255,255,0.7);
  line-height: 1.8;
  margin-bottom: 36px;
}

.hero-btns {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  border: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  color: #fff;
  box-shadow: 0 4px 16px rgba(0,180,216,0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(0,180,216,0.4);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border: 1px solid rgba(255,255,255,0.3);
}

.btn-outline:hover {
  background: rgba(255,255,255,0.1);
  border-color: rgba(255,255,255,0.5);
}

.hero-stats {
  display: flex;
  gap: 48px;
  margin-top: 64px;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,0.1);
}

.hero-stat h3 {
  font-size: 32px;
  font-weight: 800;
  color: var(--accent-light);
}

.hero-stat p {
  font-size: 14px;
  color: rgba(255,255,255,0.5);
  margin-bottom: 0;
}

/* ========== SECTIONS ========== */
.section {
  padding: 100px 0;
}

.section-light {
  background: var(--bg-white);
}

.section-gray {
  background: var(--bg-light);
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-header .label {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 12px;
}

.section-header h2 {
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 800;
  color: var(--text-dark);
  margin-bottom: 16px;
}

.section-header p {
  font-size: 16px;
  color: var(--text-light);
  max-width: 600px;
  margin: 0 auto;
}

/* ========== ABOUT ========== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.about-text h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text-dark);
}

.about-text p {
  font-size: 15px;
  color: var(--text-mid);
  line-height: 1.8;
  margin-bottom: 16px;
}

.about-features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 32px;
}

.about-feature {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.about-feature-icon {
  width: 40px;
  height: 40px;
  min-width: 40px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 18px;
}

.about-feature span {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dark);
  line-height: 1.4;
  padding-top: 8px;
}

.about-image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
  min-height: 420px;
}

.about-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  position: absolute;
  inset: 0;
}

.about-image-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(15,76,129,0.75), rgba(0,180,216,0.55));
  z-index: 1;
}

.about-image .stat-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  position: relative;
  z-index: 2;
  padding: 32px;
  height: 100%;
  align-content: center;
}

.about-image .stat-item {
  text-align: center;
  padding: 24px 16px;
  background: rgba(255,255,255,0.12);
  border-radius: var(--radius);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255,255,255,0.15);
  transition: transform var(--transition);
}

.about-image .stat-item:hover {
  transform: scale(1.05);
}

.about-image .stat-item h4 {
  font-size: 32px;
  font-weight: 800;
  color: #fff;
  margin-bottom: 4px;
}

.about-image .stat-item p {
  font-size: 13px;
  color: rgba(255,255,255,0.8);
}

/* ========== BANNER ========== */
.banner {
  position: relative;
  padding: 80px 0;
  overflow: hidden;
}

.banner-bg {
  position: absolute;
  inset: 0;
}

.banner-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.banner-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(10,22,40,0.88), rgba(15,76,129,0.82));
}

.banner-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: #fff;
}

.banner-content h2 {
  font-size: clamp(24px, 3.5vw, 36px);
  font-weight: 800;
  margin-bottom: 16px;
}

.banner-content p {
  font-size: 16px;
  color: rgba(255,255,255,0.75);
  max-width: 640px;
  margin: 0 auto 32px;
  line-height: 1.8;
}

/* ========== SERVICES ========== */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.service-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
}

.service-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.service-card-img {
  height: 180px;
  overflow: hidden;
  position: relative;
}

.service-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.service-card:hover .service-card-img img {
  transform: scale(1.08);
}

.service-card-img::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: linear-gradient(transparent, rgba(0,0,0,0.3));
}

.service-card-body {
  padding: 28px;
}

.service-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  font-size: 20px;
  color: #fff;
}

.service-card h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text-dark);
}

.service-card p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.7;
}

/* ========== PARTNERS ========== */
.partners-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 24px;
}

.partner-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  transition: all var(--transition);
}

.partner-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.partner-logo {
  width: 64px;
  height: 64px;
  margin: 0 auto 16px;
  background: linear-gradient(135deg, rgba(15,76,129,0.06), rgba(0,180,216,0.06));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 700;
  color: var(--primary);
}

.partner-card h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 4px;
}

.partner-card p {
  font-size: 12px;
  color: var(--text-light);
}

/* ========== ADVANTAGES ========== */
.advantages-section {
  position: relative;
  overflow: hidden;
}

.advantages-bg {
  position: absolute;
  inset: 0;
}

.advantages-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.advantages-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(10,22,40,0.93), rgba(15,76,129,0.88));
}

.advantages-section .section-header .label {
  color: var(--accent-light);
}

.advantages-section .section-header h2 {
  color: #fff;
}

.advantages-section .section-header p {
  color: rgba(255,255,255,0.6);
}

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  position: relative;
  z-index: 2;
}

.advantage-card {
  text-align: center;
  padding: 40px 24px;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(4px);
  transition: all var(--transition);
}

.advantage-card:hover {
  background: rgba(255,255,255,0.1);
  border-color: rgba(0,180,216,0.3);
  transform: translateY(-4px);
}

.advantage-number {
  font-size: 48px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 12px;
}

.advantage-card h4 {
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 8px;
}

.advantage-card p {
  font-size: 14px;
  color: rgba(255,255,255,0.6);
  line-height: 1.6;
}

/* ========== CONTACT ========== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
}

.contact-info h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 16px;
}

.contact-info > p {
  font-size: 15px;
  color: var(--text-light);
  margin-bottom: 32px;
  line-height: 1.7;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 24px;
}

.contact-item-icon {
  width: 44px;
  height: 44px;
  min-width: 44px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: #fff;
}

.contact-item-text h5 {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 4px;
}

.contact-item-text p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.5;
}

.contact-map {
  border-radius: var(--radius-lg);
  overflow: hidden;
  min-height: 420px;
  position: relative;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
}

.contact-map iframe {
  width: 100%;
  height: 100%;
  min-height: 420px;
  border: none;
}

/* ========== FOOTER ========== */
.footer {
  background: var(--bg-dark);
  padding: 48px 0 32px;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  padding-bottom: 32px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-brand .footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 12px;
}

.footer-brand .footer-logo-icon {
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 14px;
}

.footer-brand p {
  font-size: 14px;
  color: rgba(255,255,255,0.5);
  max-width: 360px;
  line-height: 1.7;
}

.footer-links {
  display: flex;
  gap: 64px;
}

.footer-col h5 {
  font-size: 14px;
  font-weight: 600;
  color: rgba(255,255,255,0.8);
  margin-bottom: 16px;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 10px;
}

.footer-col a {
  font-size: 14px;
  color: rgba(255,255,255,0.5);
  transition: color var(--transition);
}

.footer-col a:hover {
  color: var(--accent-light);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
  font-size: 13px;
  color: rgba(255,255,255,0.35);
}

.footer-bottom a {
  color: rgba(255,255,255,0.5);
  transition: color var(--transition);
}

.footer-bottom a:hover {
  color: var(--accent-light);
}

/* ========== RESPONSIVE ========== */
@media (max-width: 1024px) {
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .partners-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .advantages-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: #fff;
    flex-direction: column;
    padding: 24px;
    gap: 20px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
  }

  .nav-links.active {
    display: flex;
  }

  .nav-toggle {
    display: flex;
  }

  .hero-stats {
    gap: 24px;
    flex-wrap: wrap;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .about-image {
    order: -1;
    min-height: 320px;
  }

  .services-grid {
    grid-template-columns: 1fr;
  }

  .partners-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .advantages-grid {
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }

  .contact-grid {
    grid-template-columns: 1fr;
  }

  .footer-top {
    flex-direction: column;
    gap: 32px;
  }

  .footer-links {
    gap: 40px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero-stats {
    flex-direction: column;
    gap: 16px;
  }

  .about-features {
    grid-template-columns: 1fr;
  }

  .partners-grid {
    grid-template-columns: 1fr;
  }

  .advantages-grid {
    grid-template-columns: 1fr;
  }

  .footer-links {
    flex-direction: column;
    gap: 24px;
  }
}