:root {
  --yf-ink: #18302f;
  --yf-night: #0e211f;
  --yf-teal: #2f766d;
  --yf-mist: #dde8e4;
  --yf-cloud: #f5f2ea;
  --yf-paper: #fcfbf7;
  --yf-stone: #76817e;
  --yf-line: #cbd2cf;
  --yf-dawn: #d98a54;
  --yf-info: #5f789d;
  --yf-danger: #b95c56;
  --font-ui: "Noto Sans CJK SC", "Noto Sans SC", "Noto Sans TC", system-ui, sans-serif;
  --font-editorial: "Noto Serif CJK SC", "Noto Serif SC", "Songti SC", Georgia, serif;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --max: 1180px;
  --header: 82px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background: var(--yf-cloud);
}

body {
  margin: 0;
  color: var(--yf-ink);
  font-family: var(--font-ui);
  background:
    linear-gradient(rgba(24, 48, 47, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(24, 48, 47, 0.035) 1px, transparent 1px),
    var(--yf-cloud);
  background-size: 48px 48px;
  letter-spacing: 0;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

.site-shell {
  min-height: 100vh;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 0 clamp(18px, 4vw, 56px);
  border-bottom: 1px solid rgba(24, 48, 47, 0.14);
  background: rgba(252, 251, 247, 0.88);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: max-content;
}

.brand-mark {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border: 1px solid var(--yf-line);
  border-radius: var(--radius-sm);
  background: var(--yf-paper);
}

.brand-mark img {
  width: 30px;
  height: 30px;
  display: block;
}

.brand strong {
  display: block;
  font-size: 17px;
  line-height: 1;
  font-weight: 800;
  color: var(--yf-ink);
}

.brand small {
  display: block;
  margin-top: 6px;
  color: var(--yf-teal);
  font-size: 10px;
  line-height: 1;
  text-transform: uppercase;
  letter-spacing: 2.4px;
  font-weight: 700;
}

.main-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(16px, 2vw, 30px);
  color: var(--yf-ink);
  font-size: 14px;
  font-weight: 650;
}

.main-nav a {
  position: relative;
  padding: 9px 0;
}

.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--yf-teal);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.main-nav a:hover::after {
  transform: scaleX(1);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.language-switcher {
  display: flex;
  align-items: center;
  border: 1px solid var(--yf-line);
  border-radius: var(--radius-sm);
  background: var(--yf-paper);
  overflow: hidden;
}

.language-switcher button {
  width: 38px;
  height: 36px;
  border: 0;
  border-right: 1px solid var(--yf-line);
  color: var(--yf-stone);
  background: transparent;
  font: inherit;
  font-size: 12px;
  font-weight: 700;
  cursor: pointer;
}

.language-switcher button:last-child {
  border-right: 0;
}

.language-switcher button.active {
  color: var(--yf-paper);
  background: var(--yf-teal);
}

.nav-cta,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 0 18px;
  border: 1px solid var(--yf-teal);
  border-radius: var(--radius-sm);
  font-size: 13px;
  line-height: 1.1;
  font-weight: 750;
  white-space: nowrap;
}

.nav-cta {
  color: var(--yf-paper);
  background: var(--yf-night);
  border-color: var(--yf-night);
}

.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--yf-line);
  border-radius: var(--radius-sm);
  background: var(--yf-paper);
  color: var(--yf-teal);
  padding: 0;
  flex: 0 0 auto;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  background: currentColor;
}

.section {
  position: relative;
  padding: clamp(72px, 9vw, 120px) clamp(20px, 4vw, 56px);
  scroll-margin-top: calc(var(--header) + 18px);
}

.hero {
  min-height: calc(100svh - var(--header));
  display: flex;
  align-items: center;
  padding-top: clamp(54px, 7vw, 88px);
  padding-bottom: clamp(44px, 6vw, 72px);
  background: var(--yf-cloud);
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.hero-bg::before {
  content: "";
  position: absolute;
  right: -160px;
  top: 6%;
  width: min(70vw, 860px);
  height: min(42vw, 520px);
  background: url("/assets/brand/brand-landscape.svg") center / contain no-repeat;
  opacity: 0.09;
}

.hero-grid,
.section-heading,
.business-grid,
.capability-map,
.case-grid,
.insights-layout,
.about-section,
.final-cta,
.site-footer {
  width: min(100%, var(--max));
  margin: 0 auto;
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(340px, 0.72fr);
  align-items: center;
  gap: clamp(36px, 6vw, 84px);
}

.hero-copy {
  max-width: 680px;
}

h1,
h2,
h3,
p {
  margin: 0;
}

h1 {
  max-width: 720px;
  color: var(--yf-ink);
  font-family: var(--font-editorial);
  font-size: clamp(48px, 6vw, 82px);
  line-height: 1.04;
  font-weight: 800;
  text-wrap: balance;
}

.hero-copy p {
  max-width: 610px;
  margin-top: 28px;
  color: var(--yf-stone);
  font-size: clamp(17px, 1.5vw, 21px);
  line-height: 1.75;
  font-weight: 520;
}

.hero-copy .brand-slogan {
  display: inline-flex;
  align-items: center;
  margin: 0 0 22px;
  padding: 8px 12px;
  color: var(--yf-teal);
  border: 1px solid rgba(47, 118, 109, 0.18);
  border-radius: var(--radius-sm);
  background: rgba(252, 251, 247, 0.7);
  font-size: 14px;
  line-height: 1;
  font-weight: 820;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}

.hero-actions.centered {
  justify-content: center;
}

.button.primary {
  min-width: 170px;
  color: var(--yf-paper);
  border-color: var(--yf-teal);
  background: var(--yf-teal);
  box-shadow: 0 18px 38px rgba(47, 118, 109, 0.16);
}

.button.secondary {
  color: var(--yf-teal);
  background: var(--yf-paper);
}

.button.disabled {
  color: var(--yf-stone);
  border-color: var(--yf-line);
  background: rgba(252, 251, 247, 0.7);
}

.signal-panel {
  position: relative;
  min-height: 430px;
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(24, 48, 47, 0.18);
  background:
    linear-gradient(180deg, rgba(14, 33, 31, 0.1), rgba(14, 33, 31, 0.92)),
    url("/assets/brand/brand-landscape.svg") center 18% / 112% auto no-repeat,
    var(--yf-night);
  overflow: hidden;
  box-shadow: 0 32px 70px rgba(24, 48, 47, 0.18);
}

.signal-ring {
  position: absolute;
  width: 220px;
  height: 220px;
  right: -54px;
  top: -54px;
  border: 2px solid rgba(252, 251, 247, 0.22);
  border-radius: 999px;
}

.signal-grid {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border: 1px solid rgba(252, 251, 247, 0.22);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.signal-grid span {
  min-height: 76px;
  display: grid;
  place-items: center;
  border-right: 1px solid rgba(252, 251, 247, 0.22);
  color: var(--yf-paper);
  font-size: 13px;
  font-weight: 700;
}

.signal-grid span:last-child {
  border-right: 0;
}

.signal-panel p {
  position: relative;
  margin-top: 18px;
  color: rgba(252, 251, 247, 0.72);
  font-size: 13px;
  line-height: 1.5;
}

.section-heading {
  display: grid;
  grid-template-columns: 0.62fr 1fr;
  gap: clamp(28px, 5vw, 64px);
  align-items: end;
  margin-bottom: 40px;
}

.section-heading.aligned {
  align-items: start;
}

h2 {
  color: var(--yf-ink);
  font-family: var(--font-editorial);
  font-size: clamp(32px, 4.2vw, 58px);
  line-height: 1.08;
  font-weight: 800;
  text-wrap: balance;
}

.section-heading p,
.insights-layout p,
.about-copy p,
.final-cta p {
  color: var(--yf-stone);
  font-size: 16px;
  line-height: 1.85;
}

.business-section {
  background: var(--yf-paper);
  border-top: 1px solid rgba(24, 48, 47, 0.1);
  border-bottom: 1px solid rgba(24, 48, 47, 0.1);
}

.business-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.business-card {
  min-height: 350px;
  padding: 30px;
  border: 1px solid var(--yf-line);
  border-radius: var(--radius-md);
  background: var(--yf-paper);
  box-shadow: 0 14px 34px rgba(24, 48, 47, 0.05);
}

.business-card:nth-child(1) {
  color: var(--yf-paper);
  border-color: var(--yf-night);
  background: var(--yf-night);
}

.business-card:nth-child(2) {
  background: var(--yf-mist);
}

.business-card:nth-child(3) {
  background: var(--yf-paper);
}

.business-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 34px;
  color: currentColor;
}

.business-card h3,
.case-card h3 {
  color: inherit;
  font-size: 24px;
  line-height: 1.18;
  font-weight: 800;
}

.business-card strong {
  display: block;
  margin-top: 10px;
  color: var(--yf-teal);
  font-size: 14px;
  font-weight: 760;
}

.business-card:nth-child(1) strong {
  color: var(--yf-dawn);
}

.business-card p,
.case-card p,
.insight-card p {
  margin-top: 20px;
  color: var(--yf-stone);
  font-size: 15px;
  line-height: 1.75;
}

.business-card:nth-child(1) p {
  color: rgba(252, 251, 247, 0.76);
}

.capability-section {
  background: var(--yf-cloud);
}

.capability-map {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.capability-column {
  padding: 28px;
  border: 1px solid var(--yf-line);
  border-radius: var(--radius-md);
  background: var(--yf-paper);
}

.capability-column h3 {
  color: var(--yf-teal);
  font-size: 18px;
  line-height: 1.2;
  font-weight: 800;
}

.capability-column ul {
  display: grid;
  gap: 10px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.capability-column li {
  padding: 12px 14px;
  color: var(--yf-ink);
  border: 1px solid rgba(47, 118, 109, 0.14);
  border-radius: var(--radius-sm);
  background: rgba(221, 232, 228, 0.62);
  font-size: 14px;
  font-weight: 650;
}

.cases-section {
  background: var(--yf-paper);
}

.case-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.case-card {
  min-height: 330px;
  padding: 26px;
  border: 1px solid var(--yf-line);
  border-radius: var(--radius-md);
  background: var(--yf-paper);
}

.case-card span {
  display: inline-flex;
  margin-bottom: 42px;
  padding: 7px 10px;
  color: var(--yf-teal);
  border: 1px solid rgba(47, 118, 109, 0.18);
  border-radius: 999px;
  background: var(--yf-mist);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 1.4px;
  font-weight: 800;
}

.case-card a,
.insight-card a {
  display: inline-flex;
  margin-top: 24px;
  color: var(--yf-teal);
  font-size: 14px;
  font-weight: 760;
}

.insights-section {
  background: var(--yf-cloud);
}

.insights-layout {
  display: grid;
  grid-template-columns: 0.55fr 1fr;
  gap: clamp(36px, 6vw, 76px);
}

.insight-list {
  display: grid;
  gap: 14px;
}

.insight-card {
  padding: 24px;
  border: 1px solid var(--yf-line);
  border-radius: var(--radius-md);
  background: var(--yf-paper);
}

.insight-card small {
  color: var(--yf-dawn);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 1.4px;
  font-weight: 850;
}

.insight-card h3 {
  margin-top: 12px;
  color: var(--yf-ink);
  font-size: 22px;
  line-height: 1.3;
  font-weight: 800;
}

.about-section {
  display: grid;
  grid-template-columns: 0.85fr 1fr;
  gap: clamp(40px, 6vw, 80px);
  align-items: center;
}

.about-visual {
  position: relative;
  min-height: 380px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--yf-night);
  background:
    linear-gradient(180deg, rgba(14, 33, 31, 0.04), rgba(14, 33, 31, 0.88)),
    url("/assets/brand/brand-landscape.svg") center / 100% auto no-repeat,
    var(--yf-night);
  overflow: hidden;
}

.orbit,
.node {
  display: none;
}

.about-copy {
  max-width: 660px;
}

.about-copy p {
  margin-top: 22px;
}

.final-cta {
  text-align: center;
  padding-top: 86px;
  padding-bottom: 86px;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(14, 33, 31, 0.22);
  background:
    linear-gradient(90deg, rgba(14, 33, 31, 0.96), rgba(14, 33, 31, 0.9)),
    url("/assets/brand/brand-landscape.svg") center / cover no-repeat;
}

.final-cta h2 {
  color: var(--yf-paper);
}

.final-cta p {
  max-width: 760px;
  margin: 24px auto 0;
  color: rgba(252, 251, 247, 0.74);
}

.contact-panel {
  width: min(100%, 860px);
  margin: 34px auto 0;
  display: grid;
  grid-template-columns: 1fr 1fr 178px;
  gap: 14px;
  align-items: stretch;
}

.contact-item,
.wechat-qr {
  min-height: 154px;
  padding: 20px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  border: 1px solid rgba(252, 251, 247, 0.18);
  border-radius: var(--radius-md);
  background: rgba(252, 251, 247, 0.08);
  box-shadow: inset 0 1px 0 rgba(252, 251, 247, 0.08);
}

.contact-item {
  text-align: left;
}

.contact-item span,
.wechat-qr span {
  color: rgba(252, 251, 247, 0.62);
  font-size: 12px;
  line-height: 1.2;
  text-transform: uppercase;
  letter-spacing: 1.4px;
  font-weight: 820;
}

.contact-item strong {
  margin-top: 16px;
  color: var(--yf-paper);
  font-size: clamp(18px, 2.1vw, 24px);
  line-height: 1.25;
  overflow-wrap: anywhere;
}

.wechat-qr {
  align-items: center;
  gap: 12px;
  padding: 16px;
}

.wechat-qr img {
  width: 118px;
  height: 118px;
  display: block;
  border-radius: var(--radius-sm);
  background: var(--yf-paper);
}

.final-cta .contact-note {
  margin-top: 18px;
  color: rgba(252, 251, 247, 0.62);
  font-size: 14px;
}

.site-footer {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 42px;
  padding: 52px clamp(20px, 4vw, 56px);
  border-top: 1px solid rgba(24, 48, 47, 0.12);
}

.footer-brand p {
  margin-top: 18px;
  color: var(--yf-stone);
  font-size: 13px;
  line-height: 1.7;
}

.footer-brand .footer-slogan {
  color: var(--yf-teal);
  font-weight: 800;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(2, minmax(120px, 1fr));
  gap: 16px 40px;
  color: var(--yf-ink);
  font-size: 14px;
  font-weight: 650;
}

@media (max-width: 980px) {
  :root {
    --header: 74px;
  }

  .site-header {
    height: var(--header);
  }

  .menu-toggle {
    display: block;
  }

  .main-nav,
  .header-actions {
    position: fixed;
    left: 18px;
    right: 18px;
    display: none;
    border: 1px solid var(--yf-line);
    border-radius: var(--radius-md);
    background: var(--yf-paper);
    box-shadow: 0 24px 50px rgba(24, 48, 47, 0.16);
  }

  .main-nav.open,
  .header-actions.open {
    display: grid;
  }

  .main-nav {
    top: 86px;
    padding: 18px;
    gap: 4px;
  }

  .main-nav a {
    padding: 14px 0;
  }

  .header-actions {
    top: 346px;
    padding: 16px;
    gap: 12px;
  }

  .language-switcher,
  .nav-cta {
    width: 100%;
  }

  .language-switcher button {
    flex: 1;
  }

  .hero-grid,
  .section-heading,
  .business-grid,
  .capability-map,
  .case-grid,
  .insights-layout,
  .about-section,
  .contact-panel {
    grid-template-columns: 1fr;
  }

  .contact-panel {
    max-width: 560px;
  }

  .hero {
    min-height: auto;
  }

  .signal-panel {
    min-height: 320px;
  }
}

@media (max-width: 620px) {
  .site-header {
    padding: 0 16px;
  }

  .brand-mark {
    width: 38px;
    height: 38px;
  }

  .brand-mark img {
    width: 27px;
    height: 27px;
  }

  .brand strong {
    font-size: 15px;
  }

  .brand small {
    font-size: 9px;
    letter-spacing: 1.7px;
  }

  .menu-toggle {
    position: fixed;
    top: 16px;
    left: min(calc(100vw - 58px), 332px);
    right: auto;
    z-index: 80;
    display: grid;
    place-items: center;
  }

  .menu-toggle::before {
    content: "☰";
    color: var(--yf-teal);
    font-size: 22px;
    line-height: 1;
  }

  .menu-toggle span {
    display: none;
  }

  .section {
    padding-left: 18px;
    padding-right: 18px;
  }

  .hero {
    padding-top: 56px;
  }

  .hero-bg::before {
    right: -280px;
    top: 6%;
    width: 760px;
    height: 360px;
    opacity: 0.08;
  }

  h1 {
    max-width: 100%;
    font-size: clamp(42px, 12vw, 52px);
    line-height: 1.06;
  }

  h2 {
    font-size: clamp(31px, 10vw, 42px);
  }

  .hero-copy p,
  .section-heading p,
  .insights-layout p,
  .about-copy p,
  .final-cta p {
    font-size: 16px;
  }

  .hero-copy .brand-slogan {
    max-width: 100%;
    white-space: normal;
    line-height: 1.35;
  }

  .hero-actions,
  .button {
    width: 100%;
  }

  .signal-panel {
    display: none;
  }

  .business-card,
  .capability-column,
  .case-card,
  .insight-card {
    padding: 24px;
  }

  .about-visual {
    min-height: 260px;
  }

  .final-cta {
    border-radius: var(--radius-md);
    padding: 64px 20px;
  }

  .contact-item,
  .wechat-qr {
    min-height: auto;
  }

  .contact-item {
    text-align: center;
  }

  .wechat-qr img {
    width: 142px;
    height: 142px;
  }

  .site-footer {
    flex-direction: column;
    padding-left: 18px;
    padding-right: 18px;
  }

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