:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #dbeafe;
  --secondary: #0d9488;
  --secondary-light: #ccfbf1;
  --accent: #f59e0b;
  --bg: #ffffff;
  --bg-alt: #f8fafc;
  --bg-card: #ffffff;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  --border: #e2e8f0;
  --shadow: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-hover: 0 10px 30px rgba(0,0,0,0.08);
}

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

html { scroll-behavior: smooth; }

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Nav */
nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.35rem;
  font-weight: 700;
  text-decoration: none;
  color: var(--text-primary);
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), #1e40af);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 1rem;
  color: #fff;
}

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

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  transition: color 0.2s;
}

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

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

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: 0.3s;
}

/* Hero */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, #f0f7ff 0%, #e0f2fe 50%, #f8fafc 100%);
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -30%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(37,99,235,0.06) 0%, transparent 70%);
  border-radius: 50%;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(13,148,136,0.05) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-block;
  padding: 6px 18px;
  border-radius: 50px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(2.5rem, 6vw, 4.2rem);
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.hero h1 .highlight {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.15rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 36px;
  line-height: 1.8;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.25s;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  font-weight: 700;
  box-shadow: 0 4px 16px rgba(37,99,235,0.25);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(37,99,235,0.35);
}

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

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

.scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-size: 0.8rem;
  animation: bounce 2s infinite;
}

.scroll-indicator .arrow {
  width: 20px;
  height: 20px;
  border-right: 2px solid var(--text-muted);
  border-bottom: 2px solid var(--text-muted);
  transform: rotate(45deg);
}

@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

/* Section common */
section { padding: 100px 0; }

section:nth-child(even) { background: var(--bg-alt); }

.section-label {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 50px;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.5rem);
  font-weight: 700;
  margin-bottom: 16px;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 1.05rem;
  max-width: 600px;
  line-height: 1.8;
}

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

.about-visual {
  position: relative;
  width: 100%;
  aspect-ratio: 4/3;
  border-radius: 20px;
  background: linear-gradient(135deg, #eff6ff, #f0fdfa);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.about-visual .grid-dots {
  position: absolute;
  width: 100%;
  height: 100%;
  background-image: radial-gradient(rgba(37,99,235,0.08) 1px, transparent 1px);
  background-size: 28px 28px;
}

.about-visual .center-icon {
  position: relative;
  z-index: 1;
  width: 120px;
  height: 120px;
  border-radius: 30px;
  background: linear-gradient(135deg, var(--primary-light), var(--secondary-light));
  border: 1px solid rgba(37,99,235,0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  box-shadow: var(--shadow);
}

.about-text h3 { font-size: 1.4rem; font-weight: 700; margin-bottom: 20px; }

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.9;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 32px;
}

.stat-item {
  text-align: center;
  padding: 20px 12px;
  background: var(--bg-alt);
  border-radius: 12px;
  border: 1px solid var(--border);
}

.stat-number {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--primary);
}

.stat-label {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 6px;
}

/* Services */
#services { background: var(--bg-alt); }

#services .section-header {
  text-align: center;
  margin-bottom: 56px;
}

#services .section-header .section-desc {
  margin: 0 auto;
}

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

.service-card {
  padding: 36px 28px;
  border-radius: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  transition: all 0.3s;
}

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

.service-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}

.service-icon.blue { background: var(--primary-light); color: var(--primary); }
.service-icon.purple { background: var(--secondary-light); color: var(--secondary); }
.service-icon.cyan { background: var(--primary-light); color: var(--primary); }
.service-icon.green { background: var(--secondary-light); color: var(--secondary); }
.service-icon.orange { background: #fef3c7; color: #d97706; }
.service-icon.red { background: var(--primary-light); color: var(--primary); }

.service-card h4 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.service-card p {
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.7;
}

/* Features / Values */
#values .section-header {
  text-align: center;
  margin-bottom: 56px;
}

#values .section-header .section-desc {
  margin: 0 auto;
}

.values-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.value-card {
  text-align: center;
  padding: 36px 20px;
  border-radius: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  transition: all 0.3s;
}

.value-card:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow-hover);
}

.value-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.value-card h4 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 10px;
}

.value-card p {
  color: var(--text-secondary);
  font-size: 0.88rem;
  line-height: 1.7;
}

/* CTA */
.cta {
  text-align: center;
  background: linear-gradient(135deg, #eff6ff, #f0fdfa);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.cta h2 {
  font-size: clamp(1.8rem, 3vw, 2.5rem);
  font-weight: 700;
  margin-bottom: 16px;
}

.cta p {
  color: var(--text-secondary);
  max-width: 500px;
  margin: 0 auto 32px;
}

/* Footer */
footer {
  padding: 48px 0 32px;
  border-top: 1px solid var(--border);
  background: var(--bg-alt);
}

footer .container {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
}

footer h5 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-primary);
}

footer p, footer a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.8;
  text-decoration: none;
}

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

.footer-brand .logo { margin-bottom: 12px; }

.footer-brand p {
  font-size: 0.88rem;
  max-width: 280px;
}

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

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

.footer-bottom {
  grid-column: 1 / -1;
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer-bottom a { color: var(--text-muted); }
.footer-bottom a:hover { color: var(--primary); }

/* Blog */
.blog-content {
  max-width: 800px;
  margin: 0 auto;
}

.blog-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.blog-content p {
  color: var(--text-secondary);
  line-height: 1.9;
  margin-bottom: 20px;
  font-size: 1.02rem;
}

.blog-content ul, .blog-content ol {
  margin: 12px 0 24px 24px;
  color: var(--text-secondary);
  line-height: 1.9;
}

.blog-content li {
  margin-bottom: 10px;
}

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

.blog-content .grid-2 {
  margin-top: 24px;
}

.blog-content .value-card h4 {
  font-size: 1.1rem;
}

/* FAQ */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: 12px;
  margin-bottom: 12px;
  overflow: hidden;
  background: var(--bg-card);
  box-shadow: var(--shadow);
  transition: box-shadow 0.2s;
}

.faq-item:hover {
  box-shadow: var(--shadow-hover);
}

.faq-item summary {
  padding: 18px 24px;
  font-size: 1.02rem;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--text-primary);
  transition: color 0.2s;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: '+';
  font-size: 1.4rem;
  font-weight: 300;
  color: var(--primary);
  transition: transform 0.3s;
  flex-shrink: 0;
  margin-left: 16px;
}

.faq-item[open] summary::after {
  transform: rotate(45deg);
}

.faq-item[open] summary {
  color: var(--primary);
}

.faq-answer {
  padding: 0 24px 18px;
  color: var(--text-secondary);
  line-height: 1.8;
  font-size: 0.95rem;
}

.faq-answer p {
  margin-bottom: 12px;
}

.faq-answer ul, .faq-answer ol {
  margin: 8px 0 16px 20px;
}

.faq-answer li {
  margin-bottom: 8px;
}

.faq-answer a {
  color: var(--primary);
  text-decoration: none;
}

.faq-answer a:hover {
  text-decoration: underline;
}

/* Responsive */
@media (max-width: 968px) {
  #about .container {
    grid-template-columns: 1fr;
    gap: 40px;
  }

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

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

  footer .container { grid-template-columns: 1fr 1fr; }
}

/* Utility classes */
.subpage-header {
  padding-top: 120px;
}

.section-header.centered {
  text-align: center;
  margin-bottom: 56px;
}

.section-header.centered .section-desc {
  margin: 0 auto;
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.grid-2.gap-wide {
  gap: 48px;
  align-items: start;
}

.about-intro-text {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.about-intro-text p {
  color: var(--text-secondary);
  line-height: 1.9;
}

.about-visual-box {
  aspect-ratio: 4/3;
  border-radius: 20px;
  background: linear-gradient(135deg, #eff6ff, #f0fdfa);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 4rem;
}

.about-stats.centered {
  max-width: 800px;
  margin: 0 auto;
}

.card-left {
  text-align: left;
}

.contact-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.contact-row {
  display: flex;
  gap: 32px;
  flex-wrap: wrap;
  justify-content: center;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text-secondary);
}

.contact-icon {
  font-size: 1.2rem;
}

.contact-group.start {
  align-items: flex-start;
  margin-top: 32px;
}

.mt-32 {
  margin-top: 32px;
}

.about-visual-box.md {
  font-size: 3rem;
}

.grid-2.narrow {
  max-width: 800px;
  margin: 0 auto;
}

  @media (max-width: 640px) {
    .nav-links {
      display: none;
      position: absolute;
      top: 70px;
      left: 0;
      right: 0;
      background: rgba(255, 255, 255, 0.98);
      flex-direction: column;
      padding: 20px 24px;
      gap: 20px;
      border-bottom: 1px solid var(--border);
    }

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

    .nav-toggle { display: flex; }

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

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

    footer .container { grid-template-columns: 1fr; }

    .hero-buttons { flex-direction: column; align-items: center; }

    .about-stats { grid-template-columns: repeat(3, 1fr); gap: 12px; }

    .stat-number { font-size: 1.5rem; }
  }