/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --primary:   #1a6cf6;
  --primary-d: #0f4fc4;
  --accent:    #00c2a8;
  --dark:      #0d1117;
  --dark2:     #161b22;
  --dark3:     #21262d;
  --text:      #e6edf3;
  --text-muted:#8b949e;
  --border:    #30363d;
  --radius:    12px;
  --transition: 0.25s ease;
}

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  background: var(--dark);
  color: var(--text);
  line-height: 1.7;
}

/* ===== HEADER ===== */
header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.logo-img {
  height: 44px;
  width: auto;
  display: block;
}

nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  padding: 6px 12px;
  border-radius: 6px;
  transition: color var(--transition), background var(--transition);
}

.nav-link:hover {
  color: var(--text);
  background: var(--dark3);
}

.lang-toggle {
  background: var(--dark3);
  color: var(--primary);
  border: 1px solid var(--primary);
  border-radius: 6px;
  padding: 5px 14px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  letter-spacing: 0.05em;
}

.lang-toggle:hover {
  background: var(--primary);
  color: #fff;
}

/* ===== HERO ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 100px 24px 60px;
  max-width: 1200px;
  margin: 0 auto;
  gap: 60px;
}

.hero-content {
  flex: 1;
  max-width: 580px;
}

.hero-title {
  font-size: clamp(36px, 5vw, 60px);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
  background: linear-gradient(135deg, #ffffff 40%, var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: 18px;
  color: var(--text-muted);
  margin-bottom: 36px;
  max-width: 480px;
}

.btn-primary {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  text-decoration: none;
  padding: 14px 32px;
  border-radius: var(--radius);
  font-size: 16px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
  box-shadow: 0 4px 20px rgba(26, 108, 246, 0.35);
}

.btn-primary:hover {
  background: var(--primary-d);
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(26, 108, 246, 0.45);
}

/* Hexgrid visual */
.hero-visual {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
}

.hexgrid {
  position: relative;
  width: 320px;
  height: 320px;
}

.hex {
  position: absolute;
  width: 100px;
  height: 115px;
  clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
  opacity: 0.7;
  animation: pulse 4s ease-in-out infinite;
}

.h1 { background: var(--primary);   top: 30px;  left: 110px; animation-delay: 0s; }
.h2 { background: var(--accent);    top: 130px; left: 30px;  animation-delay: 0.6s; opacity: 0.5; }
.h3 { background: var(--primary-d); top: 130px; left: 190px; animation-delay: 1.2s; opacity: 0.5; }
.h4 { background: var(--accent);    top: 220px; left: 110px; animation-delay: 1.8s; opacity: 0.4; }
.h5 { background: rgba(26,108,246,0.3); top: 60px;  left: 210px; animation-delay: 2.4s; width: 70px; height: 80px; }

@keyframes pulse {
  0%, 100% { transform: scale(1);    opacity: inherit; }
  50%       { transform: scale(1.06); filter: brightness(1.3); }
}

/* ===== SECTIONS ===== */
.section-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 100px 24px;
}

.section-title {
  font-size: clamp(28px, 3.5vw, 42px);
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
}

.section-sub {
  text-align: center;
  color: var(--text-muted);
  font-size: 17px;
  margin-bottom: 60px;
}

/* ===== ABOUT ===== */
.about { background: var(--dark2); }

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-top: 48px;
}

.about-text p {
  color: var(--text-muted);
  margin-bottom: 20px;
  font-size: 16px;
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.stat-card {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  transition: border-color var(--transition), transform var(--transition);
}

.stat-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
}

.stat-num {
  display: block;
  font-size: 38px;
  font-weight: 800;
  color: var(--primary);
  line-height: 1;
  margin-bottom: 8px;
}

.stat-label {
  font-size: 14px;
  color: var(--text-muted);
}

/* ===== SERVICES ===== */
.services { background: var(--dark); }

.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.service-card {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.service-card:hover {
  border-color: var(--primary);
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(26, 108, 246, 0.15);
}

.service-icon {
  font-size: 36px;
  margin-bottom: 20px;
}

.service-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
}

.service-card p {
  color: var(--text-muted);
  font-size: 15px;
  line-height: 1.75;
}

/* ===== GLOBAL PRESENCE ===== */
.global { background: var(--dark); }

#presence-map {
  width: 100%;
  height: 420px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  margin-bottom: 48px;
  display: block;
  background: #080c12;
}

.global-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.global-card {
  background: var(--dark2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.global-card:hover {
  border-color: var(--accent);
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(0, 194, 168, 0.12);
}

.global-card.featured {
  border-color: var(--primary);
  background: linear-gradient(135deg, var(--dark2) 70%, rgba(26, 108, 246, 0.08));
}

.global-card.featured:hover {
  border-color: var(--primary);
  box-shadow: 0 12px 40px rgba(26, 108, 246, 0.2);
}

.global-flag {
  font-size: 40px;
  margin-bottom: 16px;
  line-height: 1;
}

.global-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 4px;
}

.global-city {
  font-size: 13px;
  color: var(--accent);
  margin-bottom: 12px;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.global-card p:last-child {
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.75;
}

/* ===== WHY US ===== */
.why-us { background: var(--dark2); }

.why-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 32px;
  margin-top: 60px;
}

.why-item {
  text-align: center;
  padding: 24px;
}

.why-icon {
  font-size: 40px;
  margin-bottom: 16px;
}

.why-item h4 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
}

.why-item p {
  color: var(--text-muted);
  font-size: 14px;
}

/* ===== FOOTER ===== */
footer {
  background: var(--dark2);
  border-top: 1px solid var(--border);
  padding: 28px 24px;
  text-align: center;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  color: var(--text-muted);
  font-size: 14px;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .hero {
    flex-direction: column;
    padding-top: 120px;
    text-align: center;
  }

  .hero-sub { margin: 0 auto 36px; }

  .hero-visual { display: none; }

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

  nav .nav-link { display: none; }

  .logo-en { display: none; }
}

/* ===== ANIMATIONS on scroll ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: none;
}