:root {
  --bg: #f7f8fb;
  --surface: #fff;
  --ink: #101318;
  --muted: #5d6675;
  --subtle: #8a94a6;
  --line: rgba(16, 19, 24, .1);
  --blue: #1769ff;
  --teal: #00a985;
  --radius: 8px;
  --max: 1180px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  min-width: 320px;
  color: var(--ink);
  background: linear-gradient(180deg, #fff 0, var(--bg) 740px);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
.container { width: min(var(--max), calc(100% - 40px)); margin: 0 auto; }

.nav { position: sticky; top: 0; z-index: 20; border-bottom: 1px solid rgba(16,19,24,.08); background: rgba(255,255,255,.88); backdrop-filter: blur(22px); }
.nav-inner { width: min(var(--max), calc(100% - 40px)); height: 72px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand-mark { display: block; width: 149px; height: 45px; background: url("/assets/yl_logo.svg") center / contain no-repeat; }
.menu-toggle { display: none; min-height: 38px; padding: 0 12px; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; font: inherit; font-size: 13px; font-weight: 700; }
.nav-links { display: flex; align-items: center; gap: 4px; list-style: none; }
.nav-links li { position: relative; }
.nav-links a { display: inline-flex; align-items: center; min-height: 38px; padding: 0 12px; border-radius: var(--radius); color: var(--muted); font-size: 14px; font-weight: 520; }
.nav-links a:hover { background: rgba(16,19,24,.05); color: var(--ink); }
.nav-dropdown { position: fixed; top: 72px; left: 0; width: 100vw; padding: 28px 0; border-bottom: 1px solid var(--line); background: rgba(255,255,255,.96); box-shadow: 0 18px 42px rgba(16,24,40,.12); opacity: 0; visibility: hidden; transform: translateY(6px); transition: .18s ease; }
.has-dropdown:hover .nav-dropdown, .has-dropdown:focus-within .nav-dropdown { opacity: 1; visibility: visible; transform: translateY(0); }
.mega-menu-inner { width: min(var(--max), calc(100% - 40px)); margin: 0 auto; display: grid; grid-template-columns: .46fr .64fr; gap: 72px; }
.mega-group { display: grid; align-content: start; }
.mega-group > span { margin-bottom: 10px; color: #0d47c5; font-size: 13px; font-weight: 760; }
.mega-group a { display: grid; min-height: auto; padding: 12px 0; border-top: 1px solid var(--line); border-radius: 0; color: var(--ink); }
.mega-group a strong { margin-bottom: 5px; font-size: 15px; }
.mega-group a small { color: var(--muted); font-size: 12px; line-height: 1.55; }
.nav-actions { min-width: max-content; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 42px; padding: 0 16px; border: 1px solid transparent; border-radius: var(--radius); font-size: 14px; font-weight: 650; line-height: 1; }
.button.primary { background: var(--ink); color: #fff; }
.button.secondary { border-color: var(--line); background: rgba(255,255,255,.72); }

.breadcrumb { padding-top: 28px; color: var(--subtle); font-size: 13px; }
.breadcrumb a:hover { color: var(--ink); }
.hero { padding: 34px 0 78px; }
.hero-grid { display: grid; grid-template-columns: minmax(0,.92fr) minmax(500px,1.08fr); gap: 46px; align-items: center; }
.eyebrow, .section-kicker { display: inline-flex; align-items: center; gap: 9px; margin-bottom: 16px; color: #0d47c5; font-size: 13px; font-weight: 760; }
.eyebrow::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--teal); box-shadow: 0 0 0 5px rgba(0,169,133,.12); }
h1 { max-width: 650px; font-size: clamp(42px,5vw,62px); line-height: 1.08; letter-spacing: 0; }
.hero-copy { max-width: 580px; margin-top: 22px; color: var(--muted); font-size: 17px; line-height: 1.9; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.hero-visual { overflow: hidden; border: 1px solid rgba(16,19,24,.06); border-radius: 12px; background: #f9fafb; }
.hero-visual img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }

.section { padding: 82px 0; }
.band { background: var(--surface); }
.section-heading { margin-bottom: 42px; }
h2 { max-width: 740px; font-size: clamp(32px,4vw,48px); line-height: 1.15; letter-spacing: 0; }
.section-lead { color: var(--muted); font-size: 16px; line-height: 1.85; }

.problem-grid, .capability-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 1px; background: var(--line); }
.problem-card, .capability-card { min-height: 202px; padding: 28px; background: #fff; }
.icon { display: inline-flex; align-items: center; justify-content: center; width: 42px; height: 42px; margin-bottom: 24px; border: 1px solid rgba(23,105,255,.2); border-radius: 8px; color: var(--blue); background: #f7faff; }
.icon svg { width: 21px; height: 21px; stroke: currentColor; stroke-width: 1.7; fill: none; stroke-linecap: round; stroke-linejoin: round; }
.problem-card h3, .capability-card h3 { margin-bottom: 8px; font-size: 18px; line-height: 1.35; }
.problem-card p, .capability-card p { color: var(--muted); font-size: 15px; line-height: 1.75; }

.journey { display: grid; grid-template-columns: repeat(6, minmax(0,1fr)); gap: 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.journey-item { position: relative; min-height: 198px; padding: 22px 20px 24px 0; }
.journey-item:not(:last-child)::after { content: ""; position: absolute; top: 42px; right: 12px; width: 34px; height: 1px; background: var(--line); }
.journey-number { display: block; margin-bottom: 26px; color: var(--blue); font-size: 12px; font-weight: 760; }
.journey-item h3 { margin-bottom: 8px; font-size: 16px; }
.journey-item p { max-width: 145px; color: var(--muted); font-size: 13px; line-height: 1.7; }

.capability-grid { grid-template-columns: repeat(3, minmax(0,1fr)); gap: 12px; background: transparent; }
.capability-card { min-height: 0; padding: 0 0 25px; border-radius: 8px; overflow: hidden; }
.capability-card > img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; border-bottom: 1px solid var(--line); }
.capability-card > h3, .capability-card > p, .capability-card > .text-link { margin-left: 24px; margin-right: 24px; }
.capability-card > h3 { margin-top: 21px; }
.capability-card .text-link { display: inline-flex; margin-top: 15px; color: #0d47c5; font-size: 13px; font-weight: 700; }

.scenario-list { border-top: 1px solid var(--line); }
.scenario { display: grid; grid-template-columns: 150px minmax(0,.68fr) minmax(0,1fr); gap: 28px; padding: 24px 0; border-bottom: 1px solid var(--line); }
.scenario h3 { font-size: 16px; }
.scenario p { color: var(--muted); font-size: 15px; }
.scenario span { color: #0d47c5; font-size: 14px; font-weight: 700; }

.implementation { display: grid; grid-template-columns: repeat(4,minmax(0,1fr)); border-top: 1px solid var(--line); }
.implementation-item { padding: 24px 22px 20px 0; border-bottom: 1px solid var(--line); }
.implementation-item:not(:last-child) { border-right: 1px solid var(--line); padding-right: 22px; margin-right: 22px; }
.implementation-item span { display: block; margin-bottom: 24px; color: var(--blue); font-size: 13px; font-weight: 760; }
.implementation-item h3 { margin-bottom: 10px; font-size: 17px; }
.implementation-item p { color: var(--muted); font-size: 14px; line-height: 1.75; }

.boundary-grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 28px; }
.boundary { padding-top: 22px; border-top: 1px solid var(--line); }
.boundary h3 { margin-bottom: 10px; font-size: 17px; }
.boundary p { color: var(--muted); font-size: 15px; }

.article-link { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 18px; padding: 20px 0; border-top: 1px solid var(--line); }
.article-link:last-child { border-bottom: 1px solid var(--line); }
.article-link .icon { width: 38px; height: 38px; margin: 0; }
.article-link strong { font-size: 16px; }
.article-link span { color: var(--muted); font-size: 14px; }
.arrow { color: var(--blue); font-size: 22px; line-height: 1; }

.cta { padding: 74px 0; }
.cta-panel { display: flex; align-items: center; justify-content: space-between; gap: 28px; padding: 44px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.cta-panel p { max-width: 600px; margin-top: 12px; color: var(--muted); }
.footer { border-top: 1px solid var(--line); padding: 34px 0; color: var(--subtle); font-size: 13px; }
.footer a { color: var(--muted); }

@media (max-width: 980px) {
  .nav-inner { height: 64px; flex-wrap: wrap; gap: 10px 16px; }
  .menu-toggle { display: inline-flex; margin-left: auto; align-items: center; }
  .nav-links { display: none; order: 3; width: 100%; padding: 12px 0 14px; border-top: 1px solid var(--line); flex-direction: column; align-items: stretch; }
  .nav.is-menu-open .nav-inner { height: auto; align-items: flex-start; }
  .nav.is-menu-open .nav-links { display: flex; }
  .nav-links a { width: 100%; padding: 8px 0; }
  .nav-actions, .nav-dropdown { display: none; }
  .hero-grid { grid-template-columns: 1fr; }
  .hero-grid { gap: 30px; }
  .journey { grid-template-columns: repeat(3,minmax(0,1fr)); }
  .journey-item:nth-child(3)::after { display: none; }
  .implementation { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .implementation-item:nth-child(2) { border-right: 0; margin-right: 0; }
}

@media (max-width: 620px) {
  .container, .nav-inner { width: min(100% - 28px,var(--max)); }
  .hero { padding: 26px 0 56px; }
  .section { padding: 58px 0; }
  .problem-grid, .capability-grid, .boundary-grid { grid-template-columns: 1fr; }
  .journey, .implementation { grid-template-columns: 1fr; }
  .journey-item { min-height: auto; padding-right: 0; }
  .journey-item::after { display: none; }
  .scenario { grid-template-columns: 1fr; gap: 8px; }
  .implementation-item, .implementation-item:not(:last-child) { margin: 0; padding-right: 0; border-right: 0; }
  .cta-panel { display: grid; }
}