:root {
  --ink: #18181b;
  --text: #3f3f46;
  --muted: #71717a;
  --line: #e9eaed;
  --soft: #f7f8fa;
  --blue: #4f6ef7;
  --blue-dark: #405de6;
  --night: #15171a;
  --container: 1180px;
  --shadow: 0 1px 2px rgba(16, 24, 40, .03), 0 12px 36px rgba(16, 24, 40, .06);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  background: #fff;
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; background: #fff; color: var(--ink); -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button, input { font: inherit; }
.container { width: min(var(--container), calc(100% - 48px)); margin-inline: auto; }

.site-header { position: sticky; top: 0; z-index: 20; height: 72px; background: rgba(255,255,255,.92); border-bottom: 1px solid transparent; backdrop-filter: blur(18px); transition: border-color .18s ease, box-shadow .18s ease; }
.site-header.is-scrolled { border-color: var(--line); box-shadow: 0 3px 16px rgba(16,24,40,.035); }
.header-inner { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { display: inline-flex; align-items: center; gap: 11px; flex: 0 0 auto; }
.brand-mark { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 9px; background: #f1f4ff; }
.brand-mark svg { width: 24px; height: 24px; fill: #223b92; }
.brand-mark .brand-mark-accent { fill: var(--blue); }
.brand > span:last-child { display: grid; gap: 1px; }
.brand strong { font-size: 17px; line-height: 1; letter-spacing: .08em; }
.brand small { color: var(--muted); font-size: 10px; letter-spacing: .06em; }
.desktop-nav { display: flex; align-items: center; gap: 30px; margin-left: auto; }
.desktop-nav a { position: relative; color: #52525b; font-size: 13px; transition: color .18s ease; }
.desktop-nav a:hover, .desktop-nav a.is-active { color: var(--ink); }
.desktop-nav a.is-active::after { position: absolute; right: 0; bottom: -26px; left: 0; height: 2px; background: var(--ink); content: ""; }
.header-actions { display: flex; align-items: center; gap: 16px; flex: 0 0 auto; }
.text-link { color: var(--muted); font-size: 13px; }
.button { display: inline-flex; min-height: 42px; align-items: center; justify-content: center; gap: 9px; padding: 0 18px; border: 1px solid transparent; border-radius: 9px; font-size: 13px; font-weight: 600; cursor: pointer; transition: background .18s ease, border-color .18s ease, color .18s ease, transform .18s ease; }
.button:active { transform: scale(.98); }
.button span { font-size: 14px; transition: transform .18s ease; }
.button:hover span { transform: translate(2px, -1px); }
.button-dark { color: #fff; background: var(--night); }
.button-dark:hover { background: #27272a; }
.button-primary { color: #fff; background: var(--blue); }
.button-primary:hover { background: var(--blue-dark); }
.button-quiet { color: var(--ink); border-color: #dedfe3; background: #fff; }
.button-quiet:hover { border-color: #c9cbd1; background: #fafafa; }
.button-light { color: var(--ink); background: #fff; }
.button-light:hover { background: #f4f4f5; }
.menu-toggle { display: none; width: 38px; height: 38px; padding: 0 9px; border: 0; border-radius: 8px; background: transparent; }
.menu-toggle span { display: block; height: 1px; margin: 5px 0; background: var(--ink); }
.mobile-nav { display: none; }

.hero { overflow: hidden; padding: 96px 0 104px; border-bottom: 1px solid var(--line); }
.hero-grid { display: grid; grid-template-columns: .9fr 1.1fr; align-items: center; gap: 90px; }
.eyebrow { margin: 0 0 18px; color: var(--blue); font-size: 11px; font-weight: 700; letter-spacing: .16em; }
.hero h1 { max-width: 650px; margin: 0; font-size: clamp(44px, 5.2vw, 72px); font-weight: 600; line-height: 1.12; letter-spacing: -.055em; }
.hero-lead { max-width: 600px; margin: 27px 0 0; color: var(--muted); font-size: 17px; line-height: 1.85; }
.hero-actions { display: flex; gap: 11px; margin-top: 36px; }
.hero-visual { position: relative; min-height: 430px; border-radius: 22px; background: #f5f7fb; isolation: isolate; }
.visual-grid { position: absolute; inset: 0; z-index: -1; border-radius: inherit; opacity: .35; background-image: linear-gradient(#dfe4ef 1px, transparent 1px), linear-gradient(90deg, #dfe4ef 1px, transparent 1px); background-size: 38px 38px; mask-image: linear-gradient(to bottom right, #000, transparent 85%); }
.workflow-card { position: absolute; border: 1px solid rgba(227,229,235,.9); background: rgba(255,255,255,.96); box-shadow: var(--shadow); }
.workflow-main { top: 92px; right: 38px; left: 38px; padding: 25px 24px 29px; border-radius: 16px; }
.workflow-heading { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 9px; padding-bottom: 21px; border-bottom: 1px solid var(--line); font-size: 13px; font-weight: 600; }
.workflow-heading small { color: var(--muted); font-size: 11px; font-weight: 400; }
.signal { width: 7px; height: 7px; border-radius: 50%; background: #22c55e; box-shadow: 0 0 0 4px #e8f8ee; }
.workflow-steps { display: grid; grid-template-columns: 1fr 28px 1fr 28px 1fr; align-items: center; gap: 5px; padding-top: 27px; }
.workflow-steps div { display: grid; gap: 6px; }
.workflow-steps div span { display: grid; width: 30px; height: 30px; place-items: center; border-radius: 8px; color: var(--blue); background: #eef1ff; font-size: 10px; font-weight: 700; }
.workflow-steps strong { margin-top: 7px; font-size: 14px; font-weight: 600; }
.workflow-steps small { color: var(--muted); font-size: 11px; }
.workflow-steps i { height: 1px; background: #dcdfe6; }
.floating-note { position: absolute; display: grid; gap: 4px; min-width: 138px; padding: 15px 17px; border: 1px solid #e7e8ec; border-radius: 12px; background: #fff; box-shadow: var(--shadow); }
.floating-note span { color: var(--muted); font-size: 10px; }
.floating-note strong { font-size: 12px; font-weight: 600; }
.note-one { right: 6px; bottom: 37px; }
.note-two { bottom: 28px; left: 21px; }

.principles { border-bottom: 1px solid var(--line); background: #fff; }
.principle-row { display: grid; grid-template-columns: repeat(3, 1fr); }
.principle-row > div { position: relative; padding: 28px 42px; border-right: 1px solid var(--line); }
.principle-row > div:first-child { padding-left: 0; }
.principle-row > div:last-child { border-right: 0; }
.principle-row span { position: absolute; top: 29px; right: 22px; color: #d4d4d8; font-size: 11px; }
.principle-row strong { font-size: 14px; font-weight: 600; }
.principle-row p { margin: 7px 0 0; color: var(--muted); font-size: 12px; line-height: 1.65; }

.section { padding: 104px 0; }
.content-section { background: #fff; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 30px; margin-bottom: 42px; }
.section-heading.compact { margin-bottom: 32px; }
.section-heading .eyebrow { margin-bottom: 12px; }
.section-heading h2, .about-section h2, .cta-section h2 { margin: 0; font-size: clamp(28px, 3vw, 40px); font-weight: 600; letter-spacing: -.035em; }
.section-heading > div > p:last-child { margin: 10px 0 0; color: var(--muted); font-size: 14px; }
.arrow-link { color: var(--muted); font-size: 13px; }
.arrow-link span { display: inline-block; margin-left: 5px; transition: transform .18s ease; }
.arrow-link:hover span { transform: translateX(3px); }
.article-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.article-card { position: relative; }
.article-card > a { position: relative; display: flex; min-height: 380px; flex-direction: column; padding: 31px 30px 28px; border-right: 1px solid var(--line); transition: background .18s ease; }
.article-card:last-child > a { border-right: 0; }
.article-card > a:hover { background: var(--soft); }
.article-meta { display: flex; align-items: center; justify-content: space-between; color: var(--muted); font-size: 11px; }
.article-meta span { color: var(--blue); font-weight: 600; }
.article-number { margin: 42px 0 15px; color: #e0e1e5; font-size: 44px; font-weight: 500; letter-spacing: -.08em; }
.article-card h3 { margin: 0; font-size: 20px; font-weight: 600; line-height: 1.48; letter-spacing: -.02em; }
.article-card p { margin: 15px 0 30px; color: var(--muted); font-size: 13px; line-height: 1.85; }
.article-foot { display: flex; align-items: center; justify-content: space-between; margin-top: auto; color: #a1a1aa; font-size: 11px; }
.article-foot i { color: var(--ink); font-size: 17px; font-style: normal; transition: transform .18s ease; }
.article-card > a:hover .article-foot i { transform: translateX(3px); }

.paths-section { background: var(--soft); }
.path-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.path-item { position: relative; min-height: 250px; padding: 29px 29px 25px; border: 1px solid transparent; border-radius: 13px; background: #fff; transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease; }
.path-item:hover { transform: translateY(-2px); border-color: #e6e7ea; box-shadow: 0 8px 30px rgba(16,24,40,.05); }
.path-item span { color: var(--blue); font-size: 11px; font-weight: 600; }
.path-item h3 { margin: 58px 0 10px; font-size: 20px; font-weight: 600; }
.path-item p { max-width: 280px; margin: 0; color: var(--muted); font-size: 13px; line-height: 1.8; }
.path-item i { position: absolute; right: 25px; bottom: 22px; font-size: 17px; font-style: normal; transition: transform .18s ease; }
.path-item:hover i { transform: translateX(3px); }

.about-section { border-top: 1px solid var(--line); }
.about-grid { display: grid; grid-template-columns: .8fr 1.2fr; gap: 100px; }
.about-body > p { max-width: 690px; margin: 0 0 18px; color: var(--text); font-size: 15px; line-height: 2; }
.contact-line { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 18px; margin-top: 33px; padding-top: 25px; border-top: 1px solid var(--line); font-size: 13px; }
.contact-line span { color: var(--muted); }
.contact-line a { color: var(--blue); }
.contact-line strong { font-weight: 500; }
.cta-section { display: flex; align-items: center; justify-content: space-between; gap: 40px; margin-bottom: 104px; padding: 55px 60px; border-radius: 16px; color: #fff; background: var(--night); }
.cta-section .eyebrow { color: #9fafff; }
.cta-section p:last-child { margin: 13px 0 0; color: #aeb0b5; font-size: 14px; }

.site-footer { padding-top: 58px; color: #c7c9ce; background: #15171a; }
.footer-main { display: grid; grid-template-columns: 1fr auto auto; gap: 100px; padding-bottom: 55px; }
.footer-brand strong { color: #fff; font-size: 20px; letter-spacing: .08em; }
.footer-brand p { margin: 12px 0 0; color: #7f828a; font-size: 12px; }
.footer-main > div:not(:first-child) { display: grid; align-content: start; gap: 11px; min-width: 120px; font-size: 12px; }
.footer-main > div:not(:first-child) span { margin-bottom: 6px; color: #fff; font-weight: 600; }
.footer-main a { color: #8d9097; transition: color .18s ease; }
.footer-main a:hover { color: #fff; }
.footer-bottom { display: flex; justify-content: space-between; gap: 24px; padding: 22px 0 26px; border-top: 1px solid #2a2c30; color: #73767e; font-size: 11px; }
.footer-bottom a:hover { color: #aaaeb7; }

.articles-page { min-height: calc(100vh - 220px); }
.page-intro { padding: 100px 0 65px; border-bottom: 1px solid var(--line); }
.page-intro .eyebrow { margin-bottom: 13px; }
.page-intro h1 { margin: 0; font-size: clamp(42px, 5vw, 64px); font-weight: 600; letter-spacing: -.05em; }
.page-intro > p:last-child { max-width: 620px; margin: 20px 0 0; color: var(--muted); font-size: 15px; line-height: 1.85; }
.content-library { padding: 44px 0 110px; }
.filter-row { display: flex; gap: 8px; margin-bottom: 34px; }
.filter-row button { padding: 8px 15px; border: 0; border-radius: 7px; color: var(--muted); background: transparent; font-size: 12px; cursor: pointer; transition: color .18s ease, background .18s ease; }
.filter-row button:hover { color: var(--ink); background: var(--soft); }
.filter-row button.is-active { color: #fff; background: var(--ink); }
.library-grid { display: grid; grid-template-columns: repeat(2, 1fr); border-top: 1px solid var(--line); }
.article-card.is-compact > a { min-height: 310px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.library-grid .article-card:nth-child(even) > a { border-right: 0; }
.article-card.is-compact .article-number { margin-top: 26px; font-size: 32px; }
.empty-content { padding: 100px 20px; text-align: center; }
.empty-content strong { font-size: 18px; font-weight: 600; }
.empty-content p { color: var(--muted); font-size: 13px; }

.article-page { padding-bottom: 100px; }
.article-shell { min-height: 70vh; }
.article-header { max-width: 900px; padding-top: 75px; padding-bottom: 58px; text-align: center; }
.article-back { display: inline-block; margin-bottom: 42px; color: var(--muted); font-size: 12px; }
.article-back:hover { color: var(--ink); }
.article-kicker { display: flex; justify-content: center; gap: 15px; margin-bottom: 22px; color: var(--muted); font-size: 11px; }
.article-kicker span:first-child { color: var(--blue); font-weight: 600; }
.article-header h1 { max-width: 840px; margin: 0 auto; font-size: clamp(35px, 4.8vw, 56px); font-weight: 600; line-height: 1.25; letter-spacing: -.045em; }
.article-header > p { max-width: 700px; margin: 23px auto 0; color: var(--muted); font-size: 15px; line-height: 1.9; }
.article-body { max-width: 760px; margin: 0 auto; padding: 55px 0 85px; border-top: 1px solid var(--line); color: #35353a; }
.article-body .lead { margin: 0 0 48px; color: var(--ink); font-size: 18px; line-height: 1.95; }
.article-body h2 { margin: 47px 0 17px; font-size: 23px; font-weight: 600; letter-spacing: -.02em; }
.article-body p, .article-body li { font-size: 15px; line-height: 2; }
.article-body p { margin: 0 0 20px; }
.article-body ul, .article-body ol { margin: 15px 0 26px; padding-left: 23px; }
.article-body li { padding-left: 5px; margin-bottom: 7px; }
.article-callout { margin: 35px 0; padding: 24px 26px; border-left: 3px solid var(--blue); background: var(--soft); }
.article-callout strong { font-size: 13px; }
.article-callout p { margin: 8px 0 0; color: var(--muted); font-size: 13px; }
.article-next { padding-top: 75px; border-top: 1px solid var(--line); }
.related-grid { display: grid; grid-template-columns: repeat(2, 1fr); border-top: 1px solid var(--line); }
.related-grid .article-card:nth-child(2) > a { border-right: 0; }
.not-found { display: grid; min-height: 65vh; place-content: center; justify-items: center; text-align: center; }
.not-found span { color: #d4d4d8; font-size: 70px; font-weight: 600; }
.not-found h1 { margin: 16px 0 0; font-size: 30px; }
.not-found p { margin: 12px 0 30px; color: var(--muted); }
.article-loading { padding: 150px 20px; color: var(--muted); text-align: center; }

.reveal { opacity: 0; transform: translateY(10px); transition: opacity .5s ease var(--delay, 0ms), transform .5s ease var(--delay, 0ms); }
.reveal.is-visible { opacity: 1; transform: none; }

@media (max-width: 980px) {
  .desktop-nav, .desktop-only { display: none; }
  .menu-toggle { display: block; }
  .mobile-nav { position: absolute; top: 71px; right: 0; left: 0; display: grid; max-height: 0; overflow: hidden; padding: 0 24px; background: #fff; opacity: 0; transition: max-height .22s ease, opacity .18s ease, padding .22s ease; }
  .mobile-nav a { padding: 13px 0; border-bottom: 1px solid var(--line); font-size: 14px; }
  .menu-open .mobile-nav { max-height: 360px; padding-top: 10px; padding-bottom: 18px; border-bottom: 1px solid var(--line); opacity: 1; }
  .hero { padding-top: 70px; }
  .hero-grid { grid-template-columns: 1fr; gap: 56px; }
  .hero-copy { max-width: 680px; }
  .hero-visual { min-height: 390px; }
  .article-grid { grid-template-columns: 1fr; }
  .article-card > a, .article-card:last-child > a { min-height: 310px; border-right: 0; border-bottom: 1px solid var(--line); }
  .article-card:last-child > a { border-bottom: 0; }
  .about-grid { grid-template-columns: 1fr; gap: 45px; }
}

@media (max-width: 720px) {
  .container { width: min(100% - 32px, var(--container)); }
  .site-header { height: 64px; }
  .brand-mark { width: 31px; height: 31px; }
  .brand small { display: none; }
  .header-actions { gap: 8px; }
  .header-actions .button { min-height: 38px; padding-inline: 13px; font-size: 12px; }
  .mobile-nav { top: 63px; }
  .hero { padding: 58px 0 70px; }
  .hero h1 { font-size: 42px; }
  .hero-lead { font-size: 15px; }
  .hero-actions { flex-wrap: wrap; }
  .hero-visual { min-height: 345px; margin-inline: -4px; }
  .workflow-main { top: 54px; right: 17px; left: 17px; padding: 20px 18px 23px; }
  .workflow-heading { grid-template-columns: auto 1fr; }
  .workflow-heading small { display: none; }
  .workflow-steps { grid-template-columns: 1fr 14px 1fr 14px 1fr; }
  .workflow-steps small { font-size: 9px; }
  .floating-note { min-width: 120px; padding: 12px 13px; }
  .note-one { right: 2px; bottom: 30px; }
  .note-two { bottom: 18px; left: 5px; }
  .principle-row { grid-template-columns: 1fr; }
  .principle-row > div, .principle-row > div:first-child { padding: 25px 0; border-right: 0; border-bottom: 1px solid var(--line); }
  .principle-row > div:last-child { border-bottom: 0; }
  .principle-row span { right: 0; }
  .section { padding: 72px 0; }
  .section-heading { align-items: start; margin-bottom: 28px; }
  .path-grid { grid-template-columns: 1fr; }
  .path-item { min-height: 210px; }
  .path-item h3 { margin-top: 37px; }
  .cta-section { align-items: start; flex-direction: column; margin-bottom: 72px; padding: 38px 30px; }
  .footer-main { grid-template-columns: 1fr 1fr; gap: 38px; }
  .footer-brand { grid-column: 1 / -1; }
  .footer-bottom { align-items: flex-start; flex-direction: column; gap: 8px; }
  .page-intro { padding: 68px 0 45px; }
  .library-grid, .related-grid { grid-template-columns: 1fr; }
  .article-card.is-compact > a, .library-grid .article-card:nth-child(even) > a, .related-grid .article-card:nth-child(2) > a { border-right: 0; }
  .article-header { padding-top: 52px; padding-bottom: 42px; }
  .article-back { margin-bottom: 30px; }
  .article-body { width: calc(100% - 32px); padding-top: 42px; }
  .article-body .lead { font-size: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
}