:root {
  --green-dark: #1B4332;
  --green-mid: #2D6A4F;
  --green-light: #40916C;
  --amber: #C2410C;
  --amber-light: #EA580C;
  --cream: #FAFAF5;
  --cream-dark: #F0EDE8;
  --ink: #1A1A18;
  --ink-mid: #3D3D3B;
  --ink-light: #6B6B68;
  --border: #E5E2DC;
}

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

body {
  font-family: 'DM Sans', sans-serif;
  background: var(--cream);
  color: var(--ink);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Nav */
.nav {
  padding: 16px 40px;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: var(--cream);
  z-index: 100;
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 40px;
}
.nav-logo {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: 22px;
  font-weight: 700;
  color: var(--green-dark);
  letter-spacing: 2px;
  text-decoration: none;
  white-space: nowrap;
}
.nav-links {
  display: flex;
  gap: 28px;
  margin-left: auto;
}
.nav-link {
  font-size: 14px;
  color: var(--ink-mid);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
  white-space: nowrap;
}
.nav-link:hover { color: var(--green-dark); }
.nav-cta {
  font-size: 13px;
  font-weight: 600;
  color: #fff;
  background: var(--green-dark);
  padding: 8px 20px;
  text-decoration: none;
  border-radius: 4px;
  transition: background 0.2s;
  white-space: nowrap;
}
.nav-cta:hover { background: var(--green-mid); }
.nav-cta--mobile { display: none; }
.nav-cta--desktop { }
.nav-hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  flex-direction: column;
  gap: 5px;
}
.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink);
  transition: transform 0.2s;
}

/* Hero */
.hero {
  max-width: 1100px;
  margin: 0 auto;
  padding: 80px 40px 60px;
}
.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.hero-headline {
  font-family: 'Playfair Display', serif;
  font-size: clamp(36px, 5vw, 56px);
  font-weight: 700;
  color: var(--green-dark);
  line-height: 1.1;
  letter-spacing: -1px;
  margin-bottom: 20px;
}
.hero-sub {
  font-size: 17px;
  color: var(--ink-mid);
  max-width: 460px;
  line-height: 1.65;
}
.hero-visual {
  display: flex;
  align-items: center;
  justify-content: center;
}
.network-diagram {
  position: relative;
  width: 280px;
  height: 280px;
}
.network-lines {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
}
.node {
  position: absolute;
  width: 84px;
  height: 84px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  font-size: 11px;
  font-weight: 600;
  line-height: 1.3;
}
.node-center {
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  background: var(--green-dark);
  color: #fff;
  width: 100px; height: 100px;
}
.node-1 { top: 0; left: 50%; transform: translateX(-50%); background: var(--cream); border: 2px solid var(--green-mid); color: var(--green-dark); }
.node-2 { top: 20%; right: 0; background: var(--cream); border: 2px solid var(--amber); color: var(--amber); }
.node-3 { bottom: 20%; right: 0; background: var(--cream); border: 2px solid var(--green-mid); color: var(--green-dark); }
.node-4 { bottom: 0; left: 50%; transform: translateX(-50%); background: var(--cream); border: 2px solid var(--amber); color: var(--amber); }
.node-label { font-size: 12px; }

.hero-stats {
  display: flex;
  align-items: center;
  gap: 0;
  margin-top: 60px;
  padding-top: 40px;
  border-top: 1px solid var(--border);
}
.stat {
  flex: 1;
  padding: 0 30px;
}
.stat:first-child { padding-left: 0; }
.stat-num {
  display: block;
  font-family: 'Playfair Display', serif;
  font-size: 32px;
  font-weight: 700;
  color: var(--green-dark);
  line-height: 1;
  margin-bottom: 8px;
}
.stat-label {
  font-size: 13px;
  color: var(--ink-light);
  line-height: 1.4;
}
.stat-div {
  width: 1px;
  height: 50px;
  background: var(--border);
}

/* Section commons */
.section-title {
  font-family: 'Playfair Display', serif;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  color: var(--green-dark);
  letter-spacing: -0.5px;
  line-height: 1.15;
  margin-bottom: 12px;
}
.section-sub {
  font-size: 16px;
  color: var(--ink-mid);
  max-width: 520px;
  line-height: 1.6;
  margin-bottom: 50px;
}

/* How it works */
.how { background: var(--green-dark); padding: 80px 40px; }
.how-inner { max-width: 1100px; margin: 0 auto; }
.how .section-title { color: #fff; }
.how .section-sub { color: rgba(255,255,255,0.7); }
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2px;
}
.step {
  background: rgba(255,255,255,0.05);
  padding: 30px 28px;
  border-left: 1px solid rgba(255,255,255,0.1);
}
.step:first-child { border-left: none; }
.step-num {
  display: block;
  font-family: 'Playfair Display', serif;
  font-size: 48px;
  font-weight: 700;
  color: var(--amber);
  opacity: 0.8;
  line-height: 1;
  margin-bottom: 20px;
}
.step h3 {
  font-size: 15px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 12px;
  line-height: 1.4;
}
.step p { font-size: 13px; color: rgba(255,255,255,0.6); line-height: 1.6; }

/* Features */
.features { padding: 80px 40px; }
.features-inner { max-width: 1100px; margin: 0 auto; }
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
}
.feature {
  background: var(--cream);
  padding: 36px 32px;
}
.feature-icon { margin-bottom: 16px; }
.feature h3 {
  font-size: 15px;
  font-weight: 600;
  color: var(--green-dark);
  margin-bottom: 10px;
  line-height: 1.35;
}
.feature p { font-size: 13px; color: var(--ink-mid); line-height: 1.65; }

/* Difference */
.diff { background: var(--cream-dark); padding: 80px 40px; }
.diff-inner { max-width: 1100px; margin: 0 auto; }
.diff-content { margin-bottom: 50px; }
.diff-lead {
  font-size: 20px;
  color: var(--ink);
  line-height: 1.5;
  margin-bottom: 16px;
  font-weight: 500;
}
.diff-body { font-size: 15px; color: var(--ink-mid); line-height: 1.7; margin-bottom: 12px; }
.diff-table {
  background: var(--cream);
  border: 1px solid var(--border);
  overflow: hidden;
}
.diff-row {
  display: grid;
  grid-template-columns: 2fr 1.5fr 1.5fr;
  padding: 14px 24px;
  font-size: 13px;
  border-bottom: 1px solid var(--border);
}
.diff-row:last-child { border-bottom: none; }
.diff-row-head {
  background: var(--green-dark);
  color: #fff;
  font-weight: 600;
  font-size: 12px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}
.diff-row:not(.diff-row-head) span:first-child { color: var(--ink-mid); font-weight: 500; }
.diff-row:not(.diff-row-head) span:nth-child(2) { color: var(--ink-light); }
.diff-row:not(.diff-row-head) span:nth-child(3) { color: var(--green-dark); font-weight: 600; }

/* Closing */
.closing { padding: 80px 40px; background: var(--green-dark); }
.closing-inner { max-width: 800px; margin: 0 auto; text-align: center; }
.closing-statement {
  font-family: 'Playfair Display', serif;
  font-size: clamp(22px, 3vw, 30px);
  color: rgba(255,255,255,0.9);
  line-height: 1.45;
  font-weight: 400;
}

/* Footer */
.footer { padding: 36px 40px; border-top: 1px solid var(--border); }
.footer-inner { max-width: 1100px; margin: 0 auto; display: flex; align-items: flex-start; justify-content: space-between; flex-wrap: wrap; gap: 20px; }
.footer-left { display: flex; flex-direction: column; gap: 6px; }
.footer-brand { font-family: 'Noto Serif SC', 'Playfair Display', serif; font-size: 18px; font-weight: 700; color: var(--green-dark); letter-spacing: 2px; }
.footer-copy { font-size: 13px; color: var(--ink-light); line-height: 1.5; }
.footer-links { display: flex; gap: 24px; align-items: center; }
.footer-link { font-size: 14px; color: var(--ink-mid); text-decoration: none; font-weight: 500; transition: color 0.2s; }
.footer-link:hover { color: var(--green-dark); }

/* ===== About Page ===== */
.about-hero {
  padding: 80px 40px 60px;
  max-width: 800px;
  margin: 0 auto;
}
.about-hero-inner { max-width: 640px; }
.about-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--amber);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 16px;
}
.about-headline {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 700;
  color: var(--green-dark);
  line-height: 1.25;
  margin-bottom: 20px;
}
.about-sub {
  font-size: 17px;
  color: var(--ink-mid);
  line-height: 1.7;
  max-width: 520px;
}

/* Story section */
.about-story {
  padding: 0 40px 80px;
}
.about-story-inner {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.story-block {
  padding: 40px 0;
  border-bottom: 1px solid var(--border);
  position: relative;
}
.story-block:last-child { border-bottom: none; }
.story-num {
  font-family: 'Playfair Display', serif;
  font-size: 56px;
  font-weight: 700;
  color: var(--amber);
  opacity: 0.2;
  line-height: 1;
  margin-bottom: 12px;
  display: block;
}
.story-title {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: 22px;
  font-weight: 600;
  color: var(--green-dark);
  margin-bottom: 12px;
  line-height: 1.3;
}
.story-text {
  font-size: 15px;
  color: var(--ink-mid);
  line-height: 1.8;
}
.story-text strong {
  color: var(--ink);
  font-weight: 600;
}

/* Values section */
.about-values {
  background: var(--green-dark);
  padding: 80px 40px;
}
.about-values-inner {
  max-width: 1100px;
  margin: 0 auto;
}
.values-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2px;
  margin-top: 40px;
}
.value-card {
  background: rgba(255,255,255,0.05);
  padding: 36px 32px;
  border-left: 1px solid rgba(255,255,255,0.1);
}
.value-card:first-child { border-left: none; }
.value-icon { margin-bottom: 20px; }
.value-card h3 {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: 18px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 12px;
}
.value-card p {
  font-size: 14px;
  color: rgba(255,255,255,0.6);
  line-height: 1.7;
}

/* About CTA */
.about-cta {
  padding: 80px 40px;
  background: var(--cream-dark);
  text-align: center;
}
.about-cta-inner {
  max-width: 600px;
  margin: 0 auto;
}
.about-cta h2 {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: clamp(24px, 3.5vw, 32px);
  font-weight: 700;
  color: var(--green-dark);
  margin-bottom: 12px;
}
.about-cta p {
  font-size: 16px;
  color: var(--ink-mid);
  margin-bottom: 28px;
  line-height: 1.6;
}
.btn-primary {
  display: inline-block;
  background: var(--green-dark);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  padding: 14px 32px;
  text-decoration: none;
  border-radius: 4px;
  transition: background 0.2s, transform 0.15s;
}
.btn-primary:hover {
  background: var(--green-mid);
  transform: translateY(-1px);
}

/* ===== Contact Page ===== */
.contact-hero {
  padding: 80px 40px 60px;
  max-width: 800px;
  margin: 0 auto;
}
.contact-hero-inner { max-width: 640px; }

/* Contact Methods */
.contact-methods {
  padding: 0 40px 80px;
}
.contact-methods-inner {
  max-width: 800px;
  margin: 0 auto;
}
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}
.contact-card {
  background: #fff;
  border: 1px solid var(--border);
  padding: 36px 32px;
  transition: box-shadow 0.2s;
}
.contact-card:hover {
  box-shadow: 0 4px 24px rgba(27, 67, 50, 0.08);
}
.contact-card-icon { margin-bottom: 20px; }
.contact-card h3 {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: 20px;
  font-weight: 600;
  color: var(--green-dark);
  margin-bottom: 8px;
}
.contact-card-desc {
  font-size: 14px;
  color: var(--ink-mid);
  margin-bottom: 24px;
  line-height: 1.6;
}
.wechat-id, .email-address {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: var(--cream);
  border: 1px solid var(--border);
  margin-bottom: 20px;
}
.wechat-label {
  font-size: 12px;
  font-weight: 600;
  color: var(--ink-light);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.wechat-value {
  font-size: 15px;
  font-weight: 600;
  color: var(--green-dark);
}
.wechat-qr { margin-top: 4px; }
.qr-placeholder {
  width: 160px;
  height: 160px;
  border: 2px dashed var(--border);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  color: var(--ink-light);
  font-size: 12px;
}

/* Process */
.contact-process {
  padding: 80px 40px;
  background: var(--cream-dark);
}
.contact-process-inner {
  max-width: 800px;
  margin: 0 auto;
}
.process-steps {
  display: flex;
  flex-direction: column;
  gap: 0;
}
.process-step {
  padding: 32px 0 32px 60px;
  position: relative;
  border-left: 2px solid var(--border);
}
.process-step:last-child { border-left-color: transparent; }
.process-step-num {
  position: absolute;
  left: -16px;
  top: 32px;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--green-dark);
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}
.process-step h3 {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: 17px;
  font-weight: 600;
  color: var(--green-dark);
  margin-bottom: 8px;
}
.process-step p {
  font-size: 14px;
  color: var(--ink-mid);
  line-height: 1.7;
}

/* FAQ */
.contact-faq {
  padding: 80px 40px;
}
.contact-faq-inner {
  max-width: 800px;
  margin: 0 auto;
}
.faq-list {
  margin-top: 40px;
  display: flex;
  flex-direction: column;
  gap: 0;
}
.faq-item {
  padding: 28px 0;
  border-bottom: 1px solid var(--border);
}
.faq-item:first-child { padding-top: 0; }
.faq-item h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--green-dark);
  margin-bottom: 8px;
}
.faq-item p {
  font-size: 14px;
  color: var(--ink-mid);
  line-height: 1.7;
}

/* ===== Floating CTA ===== */
.floating-cta {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: var(--green-dark);
  color: #fff;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 24px;
  border-radius: 50px;
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  box-shadow: 0 4px 20px rgba(27, 67, 50, 0.3);
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  z-index: 200;
}
.floating-cta:hover {
  background: var(--green-mid);
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(27, 67, 50, 0.4);
}

/* ===== Modal ===== */
.modal {
  display: none;
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  z-index: 1000;
  align-items: center;
  justify-content: center;
}
.modal--open {
  display: flex;
}
.modal-backdrop {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0,0,0,0.5);
}
.modal-content {
  position: relative;
  background: #fff;
  padding: 40px;
  max-width: 380px;
  width: 90%;
  text-align: center;
  box-shadow: 0 16px 48px rgba(0,0,0,0.15);
}
.modal-close {
  position: absolute;
  top: 12px; right: 16px;
  background: none;
  border: none;
  font-size: 24px;
  color: var(--ink-light);
  cursor: pointer;
  line-height: 1;
}
.modal-content h3 {
  font-family: 'Noto Serif SC', 'Playfair Display', serif;
  font-size: 20px;
  font-weight: 600;
  color: var(--green-dark);
  margin-bottom: 24px;
}
.modal-wechat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.modal-wechat-id {
  font-size: 14px;
  color: var(--ink-mid);
}
.modal-wechat-id strong {
  color: var(--green-dark);
}

/* Responsive */
@media (max-width: 900px) {
  .hero-content { grid-template-columns: 1fr; gap: 40px; }
  .hero-visual { display: none; }
  .steps { grid-template-columns: 1fr 1fr; }
  .feature-grid { grid-template-columns: 1fr 1fr; }
  .hero-stats { flex-direction: column; gap: 24px; }
  .stat { padding: 0; }
  .stat-div { display: none; }
  .diff-row { font-size: 12px; padding: 12px 16px; }
  .values-grid { grid-template-columns: 1fr; gap: 1px; }
  .value-card { border-left: none; border-top: 1px solid rgba(255,255,255,0.1); }
  .value-card:first-child { border-top: none; }
  .contact-grid { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  .nav { padding: 14px 20px; }
  .nav-links { display: none; }
  .nav-cta--desktop { display: none; }
  .nav-hamburger { display: flex; }
  .nav--open .nav-links {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--cream);
    padding: 20px;
    border-bottom: 1px solid var(--border);
    gap: 16px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.06);
  }
  .nav--open .nav-cta--mobile {
    display: inline-block;
    text-align: center;
    padding: 12px 20px;
    margin-top: 4px;
  }
  .hero { padding: 48px 20px 40px; }
  .how { padding: 60px 20px; }
  .features { padding: 60px 20px; }
  .diff { padding: 60px 20px; }
  .closing { padding: 60px 20px; }
  .steps { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
  .section-title { font-size: 28px; }
  .about-hero { padding: 48px 20px 40px; }
  .about-story { padding: 0 20px 60px; }
  .about-values { padding: 60px 20px; }
  .about-cta { padding: 60px 20px; }
  .contact-hero { padding: 48px 20px 40px; }
  .contact-methods { padding: 0 20px 60px; }
  .contact-process { padding: 60px 20px; }
  .contact-faq { padding: 60px 20px; }
  .about-headline { font-size: 28px; }
  .floating-cta { bottom: 16px; right: 16px; padding: 12px 20px; font-size: 13px; }
  .footer { padding: 28px 20px; }
}