/* ========================================
   NovaTech International Website - Styles
   ======================================== */

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

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --primary-bg: #eff6ff;
  --accent: #06b6d4;
  --dark: #0f172a;
  --dark-light: #1e293b;
  --gray-50: #f8fafc;
  --gray-100: #f1f5f9;
  --gray-200: #e2e8f0;
  --gray-300: #cbd5e1;
  --gray-400: #94a3b8;
  --gray-500: #64748b;
  --gray-600: #475569;
  --gray-700: #334155;
  --gray-800: #1e293b;
  --gray-900: #0f172a;
  --white: #ffffff;
  --font-en: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-zh: 'Noto Sans SC', 'Inter', sans-serif;
  --radius-sm: 6px;
  --radius: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
}

html { scroll-behavior: smooth; scroll-padding-top: 80px; }

body {
  font-family: var(--font-en);
  font-size: 16px;
  line-height: 1.6;
  color: var(--gray-800);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}

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

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

/* ---------- NAVBAR ---------- */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transition: var(--transition);
}
.navbar.scrolled { box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06); }
.nav-container {
  display: flex; align-items: center; justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex; align-items: center; gap: 8px;
  font-size: 20px; font-weight: 700; color: var(--dark);
}
.logo-icon { width: 36px; height: 36px; object-fit: contain; border-radius: 6px; }

.nav-links { display: flex; gap: 32px; align-items: center; }
.nav-links a {
  font-size: 14px; font-weight: 500; color: var(--gray-600);
  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(--primary);
  border-radius: 2px; transition: width var(--transition);
}
.nav-links a:hover::after { width: 100%; }

.nav-actions { display: flex; align-items: center; gap: 16px; }
.lang-switcher { display: flex; align-items: center; gap: 0; }
.lang-btn {
  background: none; border: none; cursor: pointer;
  font-size: 13px; font-weight: 500; color: var(--gray-400);
  padding: 4px 8px; transition: color var(--transition);
  font-family: var(--font-en);
}
.lang-btn:hover { color: var(--gray-600); }
.lang-btn.active { color: var(--primary); font-weight: 600; }
.lang-divider { color: var(--gray-300); font-size: 13px; }

.mobile-menu-btn {
  display: none; flex-direction: column; gap: 5px;
  background: none; border: none; cursor: pointer; padding: 4px;
}
.mobile-menu-btn span {
  display: block; width: 22px; height: 2px;
  background: var(--gray-700); border-radius: 2px;
  transition: var(--transition);
}

/* ---------- HERO ---------- */
.hero {
  position: relative; min-height: 100vh; display: flex;
  align-items: center; justify-content: center;
  background: linear-gradient(160deg, #f0f7ff 0%, #f8fafc 30%, #eff6ff 70%, #f0f7ff 100%);
  overflow: hidden; padding: 120px 0 80px;
}

.hero-bg-shapes { position: absolute; inset: 0; overflow: hidden; pointer-events: none; }
.shape { position: absolute; border-radius: 50%; opacity: 0.3; }
.shape-1 {
  width: 600px; height: 600px; background: radial-gradient(circle, rgba(37,99,235,0.08), transparent 70%);
  top: -200px; right: -150px;
}
.shape-2 {
  width: 400px; height: 400px; background: radial-gradient(circle, rgba(6,182,212,0.06), transparent 70%);
  bottom: -100px; left: -100px;
}
.shape-3 {
  width: 300px; height: 300px; background: radial-gradient(circle, rgba(37,99,235,0.05), transparent 70%);
  top: 50%; left: 50%; transform: translate(-50%, -50%);
}

.hero-content {
  position: relative; z-index: 1; text-align: center;
  display: flex; flex-direction: column; align-items: center;
}

.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--white); border: 1px solid var(--gray-200);
  border-radius: 50px; padding: 8px 20px;
  font-size: 14px; color: var(--gray-600); margin-bottom: 32px;
  animation: fadeInUp 0.6s ease-out;
}
.badge-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: #22c55e; animation: pulse-dot 2s infinite;
}

.hero-title { font-size: 64px; font-weight: 800; line-height: 1.1; margin-bottom: 24px; }
.title-line { display: block; color: var(--dark); }
.title-highlight {
  background: linear-gradient(135deg, var(--primary), #6366f1);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle {
  max-width: 620px; font-size: 18px; color: var(--gray-500);
  line-height: 1.7; margin-bottom: 40px;
}

.hero-cta { display: flex; gap: 16px; margin-bottom: 64px; flex-wrap: wrap; justify-content: center; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 14px 32px; border-radius: var(--radius);
  font-size: 15px; font-weight: 600; cursor: pointer;
  transition: all var(--transition); border: none;
}
.btn-primary {
  background: var(--primary); color: var(--white);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
}
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4); }
.btn-outline {
  background: var(--white); color: var(--primary);
  border: 1.5px solid var(--gray-200);
}
.btn-outline:hover { border-color: var(--primary); background: var(--primary-bg); }
.btn-full { width: 100%; }

.hero-stats {
  display: flex; gap: 48px; justify-content: center;
  flex-wrap: wrap; padding-top: 32px;
  border-top: 1px solid var(--gray-200);
}
.hero-stat { text-align: center; }
.stat-number { display: block; font-size: 32px; font-weight: 700; color: var(--dark); }
.stat-label { display: block; font-size: 13px; color: var(--gray-500); margin-top: 4px; }

.hero-scroll {
  position: absolute; bottom: 32px; left: 50%; transform: translateX(-50%);
  display: flex; flex-direction: column; align-items: center; gap: 4px;
  font-size: 12px; color: var(--gray-400); animation: bounce 2s infinite;
}

/* ---------- ANIMATIONS ---------- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}
@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

/* ---------- SECTIONS ---------- */
.section { padding: 100px 0; }
.section-header { text-align: center; margin-bottom: 64px; max-width: 640px; margin-left: auto; margin-right: auto; }
.section-header.light * { color: var(--white); }
.section-header.light .section-tag { color: var(--primary-light); }
.section-header.light .section-desc { color: var(--gray-400); }

.section-tag {
  display: inline-block; font-size: 13px; font-weight: 600;
  color: var(--primary); text-transform: uppercase; letter-spacing: 1.5px;
  margin-bottom: 16px;
}
.section-title { font-size: 40px; font-weight: 700; color: var(--dark); margin-bottom: 20px; line-height: 1.2; }
.section-desc { font-size: 17px; color: var(--gray-500); line-height: 1.7; }

/* ---------- CLIENTS ---------- */
.clients { padding: 48px 0 60px; background: var(--white); }
.clients-label { text-align: center; font-size: 13px; color: var(--gray-400); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 32px; }
.clients-grid {
  display: flex; justify-content: center; align-items: center; gap: 48px; flex-wrap: wrap;
}
.client-item { filter: grayscale(100%); opacity: 0.35; transition: all var(--transition); }
.client-item:hover { filter: grayscale(0); opacity: 0.7; }
.client-placeholder {
  font-size: 18px; font-weight: 700; color: var(--gray-400);
  letter-spacing: 2px;
}

/* ---------- PRODUCTS ---------- */
.products { background: var(--white); }
.products-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}

.product-card {
  background: var(--white); border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg); padding: 32px 28px;
  transition: all var(--transition); position: relative; overflow: hidden;
}
.product-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0;
  height: 3px; background: linear-gradient(90deg, var(--primary), var(--accent));
  opacity: 0; transition: opacity var(--transition);
}
.product-card:hover { border-color: var(--primary-light); transform: translateY(-4px); box-shadow: 0 12px 40px rgba(0,0,0,0.06); }
.product-card:hover::before { opacity: 1; }

.product-icon {
  width: 56px; height: 56px; display: flex; align-items: center; justify-content: center;
  background: var(--primary-bg); border-radius: var(--radius-lg);
  color: var(--primary); margin-bottom: 20px;
}
.product-card h3 { font-size: 18px; font-weight: 600; margin-bottom: 10px; color: var(--dark); }
.product-card p { font-size: 14px; color: var(--gray-500); line-height: 1.65; margin-bottom: 20px; }
.card-link {
  font-size: 14px; font-weight: 600; color: var(--primary);
  transition: gap var(--transition);
}
.card-link:hover { text-decoration: underline; }

/* ---------- ABOUT ---------- */
.about { background: var(--gray-50); }
.about-wrapper { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: start; }
.about-text .section-title { text-align: left; }
.about-desc { font-size: 16px; color: var(--gray-600); line-height: 1.75; margin-bottom: 16px; }

.about-achievements {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 32px;
}
.achievement {
  background: var(--white); border: 1px solid var(--gray-200);
  border-radius: var(--radius); padding: 20px 16px; text-align: center;
}
.achievement-number { display: block; font-size: 28px; font-weight: 700; color: var(--primary); }
.achievement-label { display: block; font-size: 12px; color: var(--gray-500); margin-top: 4px; }

.about-timeline { position: relative; padding-left: 24px; }
.about-timeline::before {
  content: ''; position: absolute; left: 7px; top: 4px; bottom: 4px;
  width: 2px; background: var(--gray-200);
}
.timeline-item { display: flex; gap: 16px; align-items: flex-start; margin-bottom: 24px; }
.timeline-item:last-child { margin-bottom: 0; }
.timeline-dot {
  flex-shrink: 0; width: 16px; height: 16px; border-radius: 50%;
  background: var(--white); border: 3px solid var(--gray-300);
  margin-top: 2px; transition: var(--transition);
}
.timeline-dot.active { border-color: var(--primary); background: var(--primary); }
.timeline-content { padding-top: 2px; }
.timeline-year { display: block; font-size: 13px; font-weight: 700; color: var(--primary); }
.timeline-text { font-size: 14px; color: var(--gray-600); }

/* ---------- GLOBAL ---------- */
.global {
  background: var(--dark); color: var(--white);
  position: relative; overflow: hidden;
}
.global::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(ellipse at 30% 50%, rgba(37, 99, 235, 0.15), transparent 60%),
              radial-gradient(ellipse at 70% 50%, rgba(6, 182, 212, 0.1), transparent 60%);
  pointer-events: none;
}

.regions-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-bottom: 48px;
  position: relative; z-index: 1;
}
.region-card {
  background: rgba(255,255,255,0.04); border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius-lg); padding: 32px;
  backdrop-filter: blur(8px); transition: var(--transition);
}
.region-card:hover { background: rgba(255,255,255,0.08); border-color: rgba(255,255,255,0.15); }
.region-header { display: flex; align-items: center; gap: 12px; margin-bottom: 20px; }
.region-flag { font-size: 28px; }
.region-header h3 { font-size: 20px; font-weight: 700; color: var(--white); }

.region-cities { display: flex; flex-direction: column; gap: 12px; }
.region-cities li { font-size: 14px; color: var(--gray-400); }
.region-cities li strong { color: var(--white); margin-right: 6px; }

.global-stats-bar {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
  padding: 32px; background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08); border-radius: var(--radius-lg);
  position: relative; z-index: 1;
}
.global-stat { text-align: center; }
.global-stat-num { display: block; font-size: 28px; font-weight: 700; color: var(--primary-light); }
.global-stat-label { display: block; font-size: 13px; color: var(--gray-400); margin-top: 4px; }

/* ---------- CERTIFICATIONS ---------- */
.certifications { background: var(--white); }
.certs-grid {
  display: grid; grid-template-columns: repeat(5, 1fr); gap: 20px;
}
.cert-card {
  text-align: center; padding: 28px 16px;
  background: var(--gray-50); border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg); transition: var(--transition);
}
.cert-card:hover { border-color: var(--primary-light); background: var(--primary-bg); }
.cert-badge {
  display: inline-block; font-size: 11px; font-weight: 700;
  color: var(--primary); background: var(--primary-bg);
  padding: 4px 10px; border-radius: 4px; margin-bottom: 12px;
  letter-spacing: 1px;
}
.cert-card h4 { font-size: 18px; font-weight: 600; color: var(--dark); margin-bottom: 6px; }
.cert-card p { font-size: 13px; color: var(--gray-500); }

/* ---------- CONTACT ---------- */
.contact { background: var(--gray-50); }
.contact-wrapper { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: start; }
.contact-info .section-title { text-align: left; }
.contact-desc { color: var(--gray-500); margin-bottom: 32px; line-height: 1.7; font-size: 16px; }

.contact-details { display: flex; flex-direction: column; gap: 16px; }
.contact-item {
  display: flex; align-items: center; gap: 12px;
  font-size: 15px; color: var(--gray-700);
}
.contact-item svg { flex-shrink: 0; color: var(--primary); }

.contact-form {
  background: var(--white); border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg); padding: 32px;
}
.form-group { margin-bottom: 20px; }
.form-group label {
  display: block; font-size: 14px; font-weight: 500;
  color: var(--gray-700); margin-bottom: 8px;
}
.form-group input,
.form-group textarea {
  width: 100%; padding: 12px 16px;
  border: 1.5px solid var(--gray-200); border-radius: var(--radius);
  font-size: 15px; font-family: var(--font-en);
  color: var(--gray-800); background: var(--white);
  transition: border-color var(--transition); outline: none;
}
.form-group input:focus,
.form-group textarea:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,0.1); }
.form-group textarea { resize: vertical; min-height: 120px; }

/* ---------- FOOTER ---------- */
.footer { background: var(--dark); color: var(--gray-400); padding: 64px 0 32px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 48px; }
.footer-logo { margin-bottom: 12px; }
.footer-logo span { color: var(--white); }
.footer-brand p { font-size: 14px; color: var(--gray-500); }

.footer-col h4 { font-size: 14px; font-weight: 600; color: var(--white); margin-bottom: 16px; }
.footer-col ul { display: flex; flex-direction: column; gap: 10px; }
.footer-col a { font-size: 14px; color: var(--gray-400); transition: color var(--transition); }
.footer-col a:hover { color: var(--white); }

.footer-bottom {
  display: flex; justify-content: space-between; align-items: center;
  padding-top: 32px; border-top: 1px solid rgba(255,255,255,0.08);
  font-size: 13px; color: var(--gray-500);
}

.footer-lang { display: flex; gap: 12px; }
.lang-btn-footer {
  background: none; border: none; cursor: pointer;
  font-size: 13px; color: var(--gray-500); transition: color var(--transition);
  font-family: var(--font-en);
}
.lang-btn-footer:hover { color: var(--white); }
.lang-btn-footer.active { color: var(--primary-light); }

/* ---------- RESPONSIVE ---------- */
@media (max-width: 1024px) {
  .hero-title { font-size: 48px; }
  .section-title { font-size: 32px; }
  .products-grid { grid-template-columns: repeat(2, 1fr); }
  .about-wrapper { grid-template-columns: 1fr; gap: 40px; }
  .regions-grid { grid-template-columns: 1fr; }
  .certs-grid { grid-template-columns: repeat(3, 1fr); }
  .contact-wrapper { grid-template-columns: 1fr; gap: 40px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .global-stats-bar { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .mobile-menu-btn { display: flex; }

  .nav-links.active {
    display: flex; flex-direction: column; position: absolute;
    top: 72px; left: 0; right: 0; background: var(--white);
    padding: 20px; border-bottom: 1px solid var(--gray-200);
    gap: 16px; box-shadow: 0 4px 20px rgba(0,0,0,0.08);
  }

  .hero { padding: 100px 0 60px; }
  .hero-title { font-size: 36px; }
  .hero-subtitle { font-size: 16px; }
  .hero-stats { gap: 24px; }
  .stat-number { font-size: 24px; }
  .hero-cta { flex-direction: column; width: 100%; max-width: 300px; }
  .hero-cta .btn { width: 100%; }

  .products-grid { grid-template-columns: 1fr; }
  .section { padding: 64px 0; }
  .section-title { font-size: 28px; }
  .about-achievements { grid-template-columns: repeat(2, 1fr); }
  .certs-grid { grid-template-columns: repeat(2, 1fr); }
  .global-stats-bar { grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .footer-grid { grid-template-columns: 1fr; }
  .clients-grid { gap: 24px; }
  .contact-form { padding: 24px; }
}

@media (max-width: 480px) {
  .hero-title { font-size: 28px; }
  .hero-stats { flex-direction: column; gap: 16px; align-items: center; }
  .about-achievements { grid-template-columns: 1fr; }
  .certs-grid { grid-template-columns: 1fr; }
  .global-stats-bar { grid-template-columns: 1fr; }
  .section { padding: 48px 0; }
}