/* ========================================
   SinoMFG Industrial Drone Website
   Dark Tech Theme
   ======================================== */

:root {
  --bg-primary: #0a0e17;
  --bg-secondary: #111827;
  --bg-card: #151d2b;
  --bg-hover: #1e293b;
  --border: #2d3748;
  --text-primary: #f9fafb;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;
  --accent: #00d4ff;
  --accent-hover: #00b8e6;
  --accent-glow: rgba(0, 212, 255, 0.3);
  --cyan: #22d3ee;
  --silver: #94a3b8;
  --success: #10b981;
  --font-cn: 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
  --font-en: 'Inter', 'Roboto', sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-cn);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: all 0.3s ease;
}

a:hover {
  color: var(--accent-hover);
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(10, 14, 23, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 24px;
  font-weight: 700;
  color: var(--text-primary);
}

.logo i {
  color: var(--accent);
  font-size: 28px;
}

.logo span span {
  color: var(--accent);
}

.nav {
  display: flex;
  gap: 32px;
}

.nav-link {
  color: var(--text-secondary);
  font-size: 15px;
  font-weight: 500;
  padding: 8px 0;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.lang-switcher {
  display: flex;
  gap: 8px;
  background: var(--bg-card);
  padding: 4px;
  border-radius: 6px;
  border: 1px solid var(--border);
}

.lang-btn {
  padding: 6px 14px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.3s ease;
}

.lang-btn.active {
  background: var(--accent);
  color: var(--bg-primary);
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: 120px 24px 80px;
  background: 
    linear-gradient(135deg, rgba(0, 212, 255, 0.05) 0%, transparent 50%),
    linear-gradient(225deg, rgba(34, 211, 238, 0.05) 0%, transparent 50%),
    var(--bg-primary);
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    linear-gradient(rgba(0, 212, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 212, 255, 0.03) 1px, transparent 1px);
  background-size: 50px 50px;
  pointer-events: none;
}

.hero-content {
  max-width: 900px;
  text-align: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: rgba(0, 212, 255, 0.1);
  border: 1px solid rgba(0, 212, 255, 0.3);
  border-radius: 50px;
  color: var(--accent);
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 32px;
}

.hero-title {
  font-size: clamp(36px, 6vw, 64px);
  font-weight: 800;
  margin-bottom: 24px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto 40px;
  line-height: 1.8;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
  margin-bottom: 48px;
}

.hero-tag {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 14px;
}

.hero-tag i {
  color: var(--accent);
}

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 32px;
  font-size: 15px;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s ease;
  border: none;
}

.btn-primary {
  background: var(--accent);
  color: var(--bg-primary);
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: 0 0 30px var(--accent-glow);
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  color: var(--text-primary);
  border: 2px solid var(--border);
}

.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* Section */
.section {
  padding: 100px 24px;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-title {
  font-size: clamp(28px, 4vw, 40px);
  margin-bottom: 16px;
}

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

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px;
  transition: all 0.3s ease;
}

.feature-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.feature-icon {
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 212, 255, 0.1);
  border-radius: 12px;
  margin-bottom: 20px;
}

.feature-icon i {
  font-size: 28px;
  color: var(--accent);
}

.feature-card h3 {
  font-size: 18px;
  margin-bottom: 12px;
}

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

/* Products Tabs */
.products-tabs {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-bottom: 48px;
}

.tab-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 28px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s ease;
}

.tab-btn i {
  font-size: 16px;
}

.tab-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.tab-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--bg-primary);
}

/* Products Grid */
.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 24px;
}

.product-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  transition: all 0.3s ease;
}

.product-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.product-img-wrap {
  display: block;
  background: linear-gradient(135deg, var(--bg-secondary), var(--bg-primary));
  padding: 40px;
  text-align: center;
  position: relative;
  overflow: hidden;
  min-height: 240px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.product-img-wrap img {
  max-width: 100%;
  max-height: 200px;
  object-fit: contain;
  transition: transform 0.3s ease;
}

.product-card:hover .product-img-wrap img {
  transform: scale(1.05);
}

.view-hint {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 12px;
  background: linear-gradient(transparent, rgba(0, 212, 255, 0.9));
  color: var(--bg-primary);
  font-size: 13px;
  font-weight: 600;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.product-card:hover .view-hint {
  opacity: 1;
}

.product-body {
  padding: 24px;
}

.product-model {
  color: var(--accent);
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 8px;
}

.product-title {
  font-size: 18px;
  margin-bottom: 16px;
}

.specs {
  margin-bottom: 20px;
}

.spec-row {
  display: flex;
  justify-content: space-between;
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
  font-size: 13px;
}

.spec-row:last-child {
  border-bottom: none;
}

.spec-label {
  color: var(--text-muted);
}

.spec-val {
  color: var(--text-primary);
  font-weight: 500;
}

.spec-val.hi {
  color: var(--accent);
}

/* Applications Grid */
.apps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
}

.app-card {
  position: relative;
  height: 200px;
  border-radius: 12px;
  overflow: hidden;
  cursor: pointer;
}

.app-bg {
  position: absolute;
  inset: 0;
  background: var(--bg-card);
  display: flex;
  align-items: center;
  justify-content: center;
}

.app-bg i {
  font-size: 64px;
  color: var(--border);
  transition: all 0.3s ease;
}

.app-card:hover .app-bg i {
  color: var(--accent);
  transform: scale(1.1);
}

.app-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(transparent, rgba(10, 14, 23, 0.95));
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 24px;
}

.app-title {
  font-size: 18px;
  margin-bottom: 8px;
}

.app-desc {
  font-size: 13px;
  color: var(--text-secondary);
}

/* Contact Section */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: 48px;
  align-items: start;
}

@media (max-width: 768px) {
  .contact-grid {
    grid-template-columns: 1fr;
  }
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

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

.contact-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 212, 255, 0.1);
  border-radius: 10px;
  flex-shrink: 0;
}

.contact-icon i {
  font-size: 20px;
  color: var(--accent);
}

.contact-label {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.contact-val {
  font-size: 15px;
  font-weight: 500;
}

/* Form */
.contact-form {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

@media (max-width: 500px) {
  .form-row {
    grid-template-columns: 1fr;
  }
}

.form-group {
  margin-bottom: 20px;
}

.form-label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 8px;
  color: var(--text-secondary);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 12px 16px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 14px;
  font-family: inherit;
  transition: border-color 0.3s ease;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--accent);
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 60px 24px 30px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  max-width: 1400px;
  margin: 0 auto;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 500px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 14px;
  margin-top: 16px;
  line-height: 1.7;
}

.footer-title {
  font-size: 15px;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 12px;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 14px;
}

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

.footer-bottom {
  max-width: 1400px;
  margin: 40px auto 0;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--text-muted);
  font-size: 13px;
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeIn 0.6s ease forwards;
}

/* Responsive */
@media (max-width: 768px) {
  .nav {
    display: none;
  }
  
  .header-inner {
    padding: 0 16px;
  }
  
  .hero {
    padding: 100px 16px 60px;
  }
  
  .hero-title {
    font-size: 32px;
  }
  
  .hero-subtitle {
    font-size: 15px;
  }
  
  .section {
    padding: 60px 16px;
  }
  
  .products-grid {
    grid-template-columns: 1fr;
  }
  
  .products-tabs {
    flex-direction: column;
  }
  
  .tab-btn {
    width: 100%;
    justify-content: center;
  }
}