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

:root {
  --color-bg: #F5F2EB;
  --color-bg-alt: #EDE9E0;
  --color-surface: #FFFFFF;
  --color-text: #2C2A25;
  --color-text-secondary: #6B655B;
  --color-text-muted: #9B948A;
  --color-primary: #5C5346;
  --color-primary-hover: #4A4338;
  --color-accent: #8B7D6B;
  --color-border: #D8D2C8;
  --color-border-light: #E8E2D8;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --max-width: 1200px;
  --header-height: 72px;
  --transition: 0.2s ease;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

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

ul {
  list-style: none;
}

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

/* ===== Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: rgba(245, 242, 235, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-light);
  z-index: 1000;
  transition: box-shadow var(--transition);
}

.site-header.scrolled {
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo img {
  height: 36px;
  width: auto;
}

.main-nav .nav-list {
  display: flex;
  gap: 32px;
  align-items: center;
}

.nav-link {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  padding: 8px 0;
  position: relative;
  transition: color var(--transition);
}

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

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--color-primary);
}

.nav-dropdown {
  position: relative;
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: -16px;
  background: var(--color-surface);
  border: 1px solid var(--color-border-light);
  border-radius: 8px;
  padding: 8px 0;
  min-width: 160px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: all var(--transition);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.nav-dropdown:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-menu a {
  display: block;
  padding: 10px 20px;
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

.dropdown-menu a:hover {
  color: var(--color-text);
  background: var(--color-bg);
}

.mobile-nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.mobile-nav-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--color-text);
  transition: all var(--transition);
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: 6px;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

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

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

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

.btn-large {
  padding: 16px 40px;
  font-size: 1rem;
}

.btn-text {
  background: none;
  color: var(--color-primary);
  padding: 8px 0;
  position: relative;
}

.btn-text::after {
  content: '';
  position: absolute;
  bottom: 4px;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--color-primary);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--transition);
}

.btn-text:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

/* ===== Hero ===== */
.hero {
  padding: calc(var(--header-height) + 80px) 24px 100px;
  text-align: center;
  background: linear-gradient(180deg, var(--color-bg) 0%, var(--color-bg-alt) 100%);
}

.hero-inner {
  max-width: 800px;
  margin: 0 auto;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.02em;
  color: var(--color-text);
  margin-bottom: 24px;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.125rem);
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 40px;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
}

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

/* ===== Stats ===== */
.section-stats {
  padding: 64px 0;
  background: var(--color-surface);
  border-top: 1px solid var(--color-border-light);
  border-bottom: 1px solid var(--color-border-light);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-item {
  padding: 16px;
}

.stat-number {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 600;
  color: var(--color-primary);
  line-height: 1.2;
  margin-bottom: 8px;
  letter-spacing: -0.02em;
}

.stat-label {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

/* ===== Sections ===== */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 64px;
}

.section-title {
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: -0.01em;
  color: var(--color-text);
  margin-bottom: 16px;
}

.section-subtitle {
  font-size: 1rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
}

/* ===== About Section ===== */
.section-about {
  background: var(--color-surface);
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  margin-bottom: 48px;
}

.about-card {
  text-align: center;
  padding: 32px 24px;
  border-radius: 12px;
  transition: all var(--transition);
}

.about-card:hover {
  background: var(--color-bg);
}

.about-card-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 20px;
  color: var(--color-accent);
}

.about-card-icon svg {
  width: 100%;
  height: 100%;
}

.about-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}

.about-card p {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.about-actions {
  display: flex;
  gap: 32px;
  justify-content: center;
}

/* ===== Features Section ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--color-surface);
  padding: 36px 28px;
  border-radius: 12px;
  border: 1px solid var(--color-border-light);
  transition: all var(--transition);
}

.feature-card:hover {
  border-color: var(--color-border);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.04);
}

.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
  line-height: 1.4;
}

.feature-card p {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ===== Capabilities Section ===== */
.section-capabilities {
  background: var(--color-surface);
}

.capabilities-list {
  max-width: 800px;
  margin: 0 auto;
}

.capability-item {
  display: flex;
  gap: 32px;
  padding: 40px 0;
  border-bottom: 1px solid var(--color-border-light);
}

.capability-item:last-child {
  border-bottom: none;
}

.capability-number {
  font-size: 2.5rem;
  font-weight: 300;
  color: var(--color-border);
  line-height: 1;
  min-width: 60px;
}

.capability-content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text);
}

.capability-content p {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
}

/* ===== Partners Section ===== */
.partners-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
  max-width: 900px;
  margin: 0 auto;
}

.partner-card {
  background: var(--color-surface);
  padding: 40px 32px;
  border-radius: 12px;
  border: 1px solid var(--color-border-light);
  text-align: center;
}

.partner-logo {
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.partner-logo img {
  max-height: 100%;
  width: auto;
}

.partner-card p {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
}

/* ===== CTA Section ===== */
.section-cta {
  background: var(--color-bg-alt);
  padding: 80px 0;
}

.cta-inner {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.cta-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--color-text);
}

.cta-subtitle {
  font-size: 1rem;
  color: var(--color-text-secondary);
  margin-bottom: 32px;
  line-height: 1.7;
}

/* ===== Footer ===== */
.site-footer {
  background: var(--color-text);
  color: var(--color-bg);
  padding: 64px 0 32px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-logo {
  height: 32px;
  margin-bottom: 16px;
  filter: brightness(0) invert(1);
  opacity: 0.9;
}

.footer-brand p {
  font-size: 0.875rem;
  opacity: 0.7;
  line-height: 1.7;
}

.footer-links h4,
.footer-contact h4 {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--color-bg);
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  font-size: 0.875rem;
  opacity: 0.7;
  transition: opacity var(--transition);
}

.footer-links a:hover {
  opacity: 1;
}

.footer-contact p {
  font-size: 0.875rem;
  opacity: 0.7;
  margin-bottom: 8px;
}

.contact-placeholder {
  font-style: italic;
  opacity: 0.5;
}

.footer-qr {
  width: 100px;
  height: 100px;
  margin-top: 16px;
  border-radius: 8px;
  background: var(--color-bg);
  padding: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 24px;
  text-align: center;
}

.footer-bottom p {
  font-size: 0.8rem;
  opacity: 0.5;
}

/* ===== Mobile Navigation ===== */
@media (max-width: 900px) {
  .mobile-nav-toggle {
    display: flex;
  }

  .main-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--color-bg);
    padding: 32px 24px;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    overflow-y: auto;
  }

  .main-nav.open {
    transform: translateX(0);
  }

  .main-nav .nav-list {
    flex-direction: column;
    gap: 0;
  }

  .nav-link {
    display: block;
    padding: 16px 0;
    font-size: 1.1rem;
    border-bottom: 1px solid var(--color-border-light);
  }

  .nav-dropdown .dropdown-menu {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    background: transparent;
    border: none;
    box-shadow: none;
    padding: 0 0 0 16px;
  }

  .dropdown-menu a {
    padding: 12px 0;
  }
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

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

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

@media (max-width: 640px) {
  :root {
    --header-height: 64px;
  }

  .hero {
    padding-top: calc(var(--header-height) + 48px);
    padding-bottom: 64px;
  }

  .section {
    padding: 64px 0;
  }

  .section-header {
    margin-bottom: 40px;
  }

  .section-stats {
    padding: 48px 0;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .about-card {
    padding: 24px 20px;
    text-align: left;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
  }

  .about-card-icon {
    margin: 0 0 12px 0;
  }

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

  .capability-item {
    flex-direction: column;
    gap: 12px;
  }

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

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

  .about-actions {
    flex-direction: column;
    gap: 16px;
    align-items: center;
  }

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

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

  .btn {
    width: 100%;
    max-width: 280px;
  }
}