/* ========================================
   HUIJIAWEI - Professional Dark Theme
   ======================================== */

:root {
  --bg-primary: #0a0e17;
  --bg-secondary: #0f172a;
  --bg-card: #111827;
  --bg-elevated: #1e293b;
  --accent-primary: #00d4aa;
  --accent-secondary: #6366f1;
  --accent-gradient: linear-gradient(135deg, #00d4aa 0%, #6366f1 100%);
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border-color: #1e293b;
  --border-light: #334155;
  --shadow-glow: 0 0 40px rgba(0, 212, 170, 0.15);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
}

a {
  color: var(--accent-primary);
  text-decoration: none;
  transition: var(--transition);
}

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

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

/* ========================================
   Header & Navigation
   ======================================== */

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(10, 14, 23, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition);
}

.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: var(--accent-gradient);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: white;
}

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

.nav-link {
  padding: 8px 16px;
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--text-primary);
  background: var(--bg-elevated);
}

.lang-switcher {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: 16px;
  padding-left: 16px;
  border-left: 1px solid var(--border-color);
}

.lang-btn {
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  background: transparent;
  border: 1px solid var(--border-color);
  cursor: pointer;
  transition: var(--transition);
}

.lang-btn:hover,
.lang-btn.active {
  color: var(--accent-primary);
  border-color: var(--accent-primary);
  background: rgba(0, 212, 170, 0.1);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
}

/* ========================================
   Hero Section
   ======================================== */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  overflow: hidden;
}

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

.hero-bg::before {
  content: '';
  position: absolute;
  top: 20%;
  left: 10%;
  width: 400px;
  height: 400px;
  background: var(--accent-primary);
  border-radius: 50%;
  filter: blur(150px);
  opacity: 0.1;
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: 10%;
  right: 10%;
  width: 500px;
  height: 500px;
  background: var(--accent-secondary);
  border-radius: 50%;
  filter: blur(180px);
  opacity: 0.08;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(rgba(30, 41, 59, 0.3) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 41, 59, 0.3) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
}

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

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: rgba(0, 212, 170, 0.1);
  border: 1px solid rgba(0, 212, 170, 0.2);
  border-radius: 100px;
  font-size: 0.85rem;
  color: var(--accent-primary);
  margin-bottom: 32px;
}

.hero-badge::before {
  content: '';
  width: 8px;
  height: 8px;
  background: var(--accent-primary);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.hero-title .gradient-text {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.15rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 40px;
}

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

/* ========================================
   Buttons
   ======================================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: none;
}

.btn-primary {
  background: var(--accent-gradient);
  color: white;
  box-shadow: 0 4px 24px rgba(0, 212, 170, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(0, 212, 170, 0.4);
  color: white;
}

.btn-secondary {
  background: var(--bg-elevated);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
}

.btn-secondary:hover {
  background: var(--border-light);
  color: var(--text-primary);
}

/* ========================================
   Section Styles
   ======================================== */

.section {
  padding: 100px 24px;
  position: relative;
}

.section-inner {
  max-width: 1280px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 64px;
}

.section-label {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid rgba(99, 102, 241, 0.2);
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  margin-bottom: 16px;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 1.05rem;
}

/* ========================================
   Cards
   ======================================== */

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 32px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--accent-gradient);
  opacity: 0;
  transition: var(--transition);
}

.card:hover {
  transform: translateY(-4px);
  border-color: var(--border-light);
  box-shadow: var(--shadow-glow);
}

.card:hover::before {
  opacity: 1;
}

.card-icon {
  width: 56px;
  height: 56px;
  background: var(--bg-elevated);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}

.card-title {
  font-size: 1.2rem;
  margin-bottom: 12px;
}

.card-text {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* ========================================
   Features / Stats
   ======================================== */

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
}

.stat-item {
  text-align: center;
  padding: 32px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
}

.stat-label {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* ========================================
   About / Content Sections
   ======================================== */

.content-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.content-row.reverse {
  direction: rtl;
}

.content-row.reverse > * {
  direction: ltr;
}

.content-visual {
  position: relative;
}

.visual-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  padding: 40px;
  position: relative;
  overflow: hidden;
}

.visual-box::after {
  content: '';
  position: absolute;
  top: -50%;
  right: -50%;
  width: 100%;
  height: 100%;
  background: var(--accent-gradient);
  opacity: 0.05;
  border-radius: 50%;
}

.content-body h3 {
  font-size: 1.8rem;
  margin-bottom: 20px;
}

.content-body p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.8;
}

.feature-list {
  list-style: none;
  margin-top: 24px;
}

.feature-list li {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 0;
  color: var(--text-secondary);
}

.feature-list li::before {
  content: '✓';
  width: 24px;
  height: 24px;
  background: rgba(0, 212, 170, 0.15);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-primary);
  font-size: 0.8rem;
  font-weight: 700;
  flex-shrink: 0;
}

/* ========================================
   Team
   ======================================== */

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

.team-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 32px;
  text-align: center;
  transition: var(--transition);
}

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

.team-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  margin: 0 auto 20px;
}

.team-role {
  color: var(--accent-primary);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.team-desc {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* ========================================
   Contact
   ======================================== */

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

.contact-info-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  margin-bottom: 16px;
}

.contact-info-icon {
  width: 48px;
  height: 48px;
  background: var(--bg-elevated);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  flex-shrink: 0;
}

.contact-info-text h4 {
  font-size: 1rem;
  margin-bottom: 4px;
}

.contact-info-text p {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.contact-form {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  padding: 40px;
}

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

.form-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 8px;
  color: var(--text-secondary);
}

.form-input {
  width: 100%;
  padding: 14px 18px;
  background: var(--bg-elevated);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  color: var(--text-primary);
  font-size: 0.95rem;
  transition: var(--transition);
  font-family: inherit;
}

.form-input:focus {
  outline: none;
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(0, 212, 170, 0.1);
}

.form-input::placeholder {
  color: var(--text-muted);
}

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

/* ========================================
   Legal Pages
   ======================================== */

.legal-section {
  padding: 140px 24px 80px;
}

.legal-inner {
  max-width: 900px;
  margin: 0 auto;
}

.legal-header {
  text-align: center;
  margin-bottom: 48px;
}

.legal-content {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  padding: 48px;
}

.legal-content h2 {
  font-size: 1.4rem;
  margin: 32px 0 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.legal-content h2:first-child {
  margin-top: 0;
}

.legal-content p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.8;
}

.legal-content ul {
  margin-left: 24px;
  margin-bottom: 16px;
  color: var(--text-secondary);
}

.legal-content ul li {
  margin-bottom: 8px;
  line-height: 1.7;
}

.legal-content a {
  color: var(--accent-primary);
}

.legal-content strong {
  color: var(--text-primary);
}

/* ========================================
   Footer
   ======================================== */

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

.footer-inner {
  max-width: 1280px;
  margin: 0 auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand p {
  color: var(--text-secondary);
  margin-top: 16px;
  font-size: 0.9rem;
  line-height: 1.7;
}

.footer-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 20px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

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

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

.footer-links a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  transition: var(--transition);
}

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

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-copy {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer-legal {
  display: flex;
  gap: 24px;
}

.footer-legal a {
  color: var(--text-muted);
  font-size: 0.85rem;
}

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

/* ========================================
   Animations
   ======================================== */

.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ========================================
   Responsive
   ======================================== */

@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav {
    display: none;
  }

  .mobile-menu-btn {
    display: block;
  }

  .content-row,
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

  .legal-content {
    padding: 28px;
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }

  .lang-switcher {
    margin-left: 8px;
    padding-left: 8px;
  }
}