:root {
  --ink: #13211d;
  --muted: #5e6d66;
  --paper: #fbfaf6;
  --panel: #ffffff;
  --line: #d8ddd5;
  --coal: #17201d;
  --pine: #0f5d4d;
  --gold: #c8942e;
  --clay: #a64f35;
  --blue: #245b83;
  --mist: #edf3ef;
  --shadow: 0 22px 60px rgba(19, 33, 29, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.55;
}

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

code,
pre {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 72px;
  padding: 14px clamp(20px, 5vw, 64px);
  color: #fff;
  background: rgba(19, 33, 29, 0.72);
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 238px;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 8px;
  background: #fff;
}

.brand strong,
.brand small {
  display: block;
}

.brand small {
  color: rgba(255, 255, 255, 0.72);
  font-size: 12px;
}

.header-nav {
  display: flex;
  justify-content: center;
  gap: 18px;
  flex: 1;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.82);
}

.header-nav a,
.launch-link,
.primary-action,
.secondary-action {
  transition:
    transform 160ms ease,
    background 160ms ease,
    border-color 160ms ease;
}

.header-nav a:hover,
.launch-link:hover,
.primary-action:hover,
.secondary-action:hover {
  transform: translateY(-1px);
}

.launch-link,
.primary-action,
.secondary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 0 18px;
  border-radius: 8px;
  font-weight: 750;
}

.launch-link,
.primary-action {
  color: #101815;
  background: #f4c14d;
}

.secondary-action {
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.38);
}

.hero {
  min-height: 86vh;
  display: grid;
  align-items: end;
  padding: 116px clamp(22px, 7vw, 92px) 56px;
  color: #fff;
  background:
    linear-gradient(90deg, rgba(13, 24, 20, 0.92) 0%, rgba(13, 24, 20, 0.72) 48%, rgba(13, 24, 20, 0.22) 100%),
    url("/assets/xuyang/industrial-landscape.png") center / cover no-repeat;
}

.hero-content {
  max-width: 1020px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--gold);
  font-size: 12px;
  font-weight: 850;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1,
.section-heading h2,
.guide-intro h2,
.workflow-content h2,
.split h2,
.governance-grid h2,
.final-cta h2 {
  margin: 0;
  line-height: 1.05;
  letter-spacing: 0;
}

.hero h1 {
  max-width: 880px;
  font-size: clamp(42px, 7vw, 92px);
}

.hero-copy {
  max-width: 690px;
  margin: 24px 0 0;
  color: rgba(255, 255, 255, 0.82);
  font-size: clamp(17px, 2vw, 21px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  max-width: 950px;
  margin: 42px 0 0;
}

.hero-metrics div {
  min-height: 122px;
  padding: 20px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
}

.hero-metrics dt {
  font-size: 24px;
  font-weight: 850;
}

.hero-metrics dd {
  margin: 8px 0 0;
  color: rgba(255, 255, 255, 0.75);
}

.section-band {
  padding: 78px clamp(20px, 5vw, 64px);
  background: var(--paper);
}

.section-band.pale {
  background: var(--mist);
}

.section-inner {
  max-width: 1200px;
  margin: 0 auto;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 34px;
}

.section-heading h2,
.guide-intro h2,
.workflow-content h2,
.split h2,
.governance-grid h2,
.final-cta h2 {
  font-size: clamp(30px, 4vw, 52px);
}

.section-heading p,
.guide-intro p,
.workflow-content p,
.split p,
.governance-grid p,
.final-cta p {
  color: var(--muted);
  font-size: 17px;
}

.intro-grid,
.split,
.governance-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: start;
}

.start-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: start;
}

.start-list li {
  position: relative;
  padding: 20px 20px 20px 64px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.start-list li::before {
  counter-increment: start;
  content: counter(start, decimal-leading-zero);
  position: absolute;
  left: 18px;
  top: 20px;
  color: var(--pine);
  font-weight: 900;
}

.role-grid,
.module-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.role-grid article,
.module-grid article {
  min-height: 210px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: 0 14px 34px rgba(19, 33, 29, 0.08);
}

.role-grid span {
  color: var(--clay);
  font-size: 12px;
  font-weight: 850;
  text-transform: uppercase;
}

.role-grid h3,
.module-grid h3,
.timeline h3 {
  margin: 8px 0 10px;
  font-size: 21px;
}

.role-grid p,
.module-grid p,
.timeline p {
  margin: 0;
  color: var(--muted);
}

.module-grid ul {
  margin: 16px 0 0;
  padding-left: 18px;
  color: var(--muted);
}

.workflow-layout {
  display: grid;
  grid-template-columns: 230px minmax(0, 1fr);
  gap: 48px;
}

.toc {
  position: sticky;
  top: 94px;
  align-self: start;
  display: grid;
  gap: 8px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.toc strong {
  margin-bottom: 6px;
}

.toc a {
  color: var(--muted);
  font-size: 14px;
}

.timeline {
  display: grid;
  gap: 14px;
  margin-top: 28px;
}

.timeline article {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 18px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.timeline span {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  color: #fff;
  border-radius: 8px;
  background: var(--pine);
  font-weight: 900;
}

.timeline h3,
.timeline p {
  grid-column: 2;
}

.timeline h3 {
  margin-top: -46px;
}

.code-panels {
  display: grid;
  gap: 14px;
}

.code-panels figure {
  margin: 0;
  overflow: hidden;
  border: 1px solid #263b33;
  border-radius: 8px;
  background: var(--coal);
  box-shadow: var(--shadow);
}

.code-panels figcaption {
  padding: 12px 16px;
  color: #f4c14d;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  font-weight: 800;
}

.code-panels pre {
  margin: 0;
  padding: 16px;
  overflow-x: auto;
  color: #e9f1ec;
  font-size: 14px;
}

.task-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.task-table {
  width: 100%;
  min-width: 820px;
  border-collapse: collapse;
}

.task-table th,
.task-table td {
  padding: 18px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.task-table th {
  color: #fff;
  background: var(--pine);
}

.task-table tbody tr:last-child td {
  border-bottom: 0;
}

.accordion-stack {
  display: grid;
  gap: 12px;
}

details {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: 0 14px 34px rgba(19, 33, 29, 0.08);
}

summary {
  cursor: pointer;
  padding: 18px 20px;
  color: var(--ink);
  font-weight: 850;
}

details p {
  margin: 0;
  padding: 0 20px 20px;
  color: var(--muted);
}

.final-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 58px clamp(20px, 5vw, 64px);
  color: #fff;
  background:
    linear-gradient(90deg, rgba(18, 30, 26, 0.94), rgba(15, 93, 77, 0.84)),
    url("/assets/xuyang/command-center-interior.png") center / cover no-repeat;
}

.final-cta > div {
  max-width: 760px;
}

.final-cta p {
  color: rgba(255, 255, 255, 0.78);
}

@media (max-width: 980px) {
  .site-header {
    position: absolute;
    flex-wrap: wrap;
  }

  .header-nav {
    order: 3;
    justify-content: flex-start;
    width: 100%;
    overflow-x: auto;
    padding-bottom: 2px;
  }

  .hero {
    min-height: 90vh;
    padding-top: 150px;
  }

  .hero-metrics,
  .intro-grid,
  .split,
  .governance-grid,
  .workflow-layout {
    grid-template-columns: 1fr;
  }

  .role-grid,
  .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .toc {
    position: static;
  }
}

@media (max-width: 680px) {
  .site-header {
    padding: 12px 16px;
  }

  .brand {
    min-width: 0;
  }

  .brand small,
  .header-nav {
    display: none;
  }

  .launch-link {
    margin-left: auto;
  }

  .hero {
    min-height: 88vh;
    padding: 112px 18px 36px;
  }

  .hero h1 {
    font-size: 40px;
  }

  .hero-metrics,
  .role-grid,
  .module-grid {
    grid-template-columns: 1fr;
  }

  .section-band {
    padding: 56px 18px;
  }

  .timeline article {
    grid-template-columns: 1fr;
  }

  .timeline h3,
  .timeline p {
    grid-column: auto;
  }

  .timeline h3 {
    margin-top: 0;
  }

  .final-cta {
    align-items: flex-start;
    flex-direction: column;
  }
}