:root {
  --ink: #0d0d0d;
  --surface: #191a1a;
  --surface-2: #222323;
  --paper: #fafaf9;
  --muted: rgba(250, 250, 249, .58);
  --faint: rgba(250, 250, 249, .09);
  --line: rgba(250, 250, 249, .18);
  --warm: #facf9f;
  --signal: #ff6123;
  --green: #67d59b;
  --blue: #7eb7ff;
  --max: 1680px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--paper);
  background:
    linear-gradient(rgba(250,250,249,.022) 1px, transparent 1px),
    linear-gradient(90deg, rgba(250,250,249,.022) 1px, transparent 1px),
    var(--ink);
  background-size: 48px 48px;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", sans-serif;
}

a { color: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }
.shell { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  min-height: 76px;
  padding: 0 max(24px, calc((100vw - var(--max)) / 2));
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  background: rgba(13, 13, 13, .92);
  backdrop-filter: blur(18px);
}

.brand { display: flex; align-items: center; gap: 13px; text-decoration: none; }
.brand-mark {
  width: 38px; height: 38px; display: grid; place-items: center;
  border: 1px solid var(--signal); color: var(--signal); font-size: 18px; font-weight: 700;
}
.brand strong, .brand small { display: block; }
.brand strong { font-size: 14px; letter-spacing: .18em; }
.brand small { margin-top: 3px; color: var(--muted); font-size: 9px; letter-spacing: .24em; }
.topbar-meta { display: flex; gap: 32px; color: var(--muted); font: 600 10px/1 Space Grotesk, sans-serif; letter-spacing: .18em; }

.hero { padding: 116px 0 88px; border-bottom: 1px solid var(--line); }
.eyebrow, .toolbar-label, .diagram-status, .mode-grid article > span, .download > div > span {
  color: var(--signal); font: 600 11px/1 Space Grotesk, sans-serif; letter-spacing: .22em;
}
.hero h1 {
  margin: 24px 0 72px;
  max-width: 1300px;
  font: 600 clamp(54px, 7.4vw, 124px)/.91 Space Grotesk, "PingFang SC", sans-serif;
  letter-spacing: -.065em;
}
.hero-grid { display: grid; grid-template-columns: 7fr 5fr; gap: 9vw; align-items: end; }
.lede { margin: 0; max-width: 760px; color: rgba(250,250,249,.8); font-size: clamp(19px, 2vw, 30px); line-height: 1.52; }
.principle { padding-top: 18px; border-top: 2px solid var(--signal); }
.principle span { color: var(--signal); font-size: 10px; letter-spacing: .16em; }
.principle strong { display: block; margin: 20px 0 12px; font-size: 21px; }
.principle p { margin: 0; color: var(--muted); line-height: 1.65; }

.toolbar { padding: 28px 0; display: flex; align-items: flex-end; justify-content: space-between; gap: 32px; border-bottom: 1px solid var(--line); }
.view-switcher { margin-top: 13px; display: flex; flex-wrap: wrap; gap: 8px; }
.view-switcher button, .download-actions a, .download-actions button {
  min-height: 42px; padding: 0 16px; border: 1px solid var(--line); border-radius: 0;
  color: var(--muted); background: transparent; cursor: pointer; transition: 160ms ease;
}
.view-switcher button:hover, .view-switcher button.active, .download-actions a:hover, .download-actions button:hover {
  border-color: var(--signal); color: var(--paper); background: rgba(255,97,35,.08);
}
.legend { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 20px; color: var(--muted); font-size: 11px; }
.legend span { display: inline-flex; align-items: center; gap: 8px; }
.swatch { width: 11px; height: 11px; border: 1px solid var(--line); }
.swatch.proprietary { background: var(--signal); border-color: var(--signal); }
.swatch.open { background: var(--surface-2); border-color: rgba(250,250,249,.45); }
.swatch.optional { border-style: dashed; }

.architecture, .flows, .modes, .boundaries, .decisions { padding: 112px 0; }
.section-heading { display: grid; grid-template-columns: 7fr 5fr; gap: 60px; align-items: end; margin-bottom: 46px; }
.section-heading > div { display: flex; align-items: baseline; gap: 20px; }
.section-heading > div > span { color: var(--signal); font: 600 11px/1 Space Grotesk, sans-serif; }
.section-heading h2 { margin: 0; font: 600 clamp(34px, 4vw, 65px)/1 Space Grotesk, "PingFang SC", sans-serif; letter-spacing: -.045em; }
.section-heading > p { margin: 0; color: var(--muted); line-height: 1.7; }

.diagram-frame { border: 1px solid var(--line); background: rgba(13,13,13,.72); }
.diagram-status { min-height: 46px; padding: 0 18px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--line); color: var(--muted); }
.status-live { display: flex; align-items: center; gap: 8px; color: var(--green); }
.status-live i { width: 7px; height: 7px; border-radius: 50%; background: var(--green); box-shadow: 0 0 0 5px rgba(103,213,155,.08); }

.actor-row { padding: 18px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--line); }
.actor-card { min-height: 148px; padding: 22px; background: var(--surface); }
.actor-card span, .pool header span, .hardware-grid article span { color: var(--signal); font: 600 9px/1 Space Grotesk, sans-serif; letter-spacing: .15em; }
.actor-card h3 { margin: 30px 0 8px; font-size: 18px; }
.actor-card p { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.5; }

.downlink { position: relative; height: 64px; display: flex; align-items: center; justify-content: center; color: var(--muted); font-size: 9px; letter-spacing: .14em; text-transform: uppercase; }
.downlink::before { content: ""; position: absolute; left: 50%; top: 0; width: 1px; height: 20px; background: var(--signal); }
.downlink::after { content: "↓"; position: absolute; left: calc(50% - 6px); bottom: 5px; color: var(--signal); }
.downlink span { padding: 7px 12px; border: 1px solid var(--faint); background: var(--ink); }
.downlink.split, .downlink.triple { justify-content: space-around; }
.downlink.split::before, .downlink.split::after, .downlink.triple::before, .downlink.triple::after { display: none; }
.downlink.split span:first-child, .downlink.triple span { color: var(--warm); }

.layer { margin: 0 18px; display: grid; grid-template-columns: 210px 1fr; border: 1px solid var(--line); }
.layer-label { padding: 24px; display: flex; flex-direction: column; border-right: 1px solid var(--line); background: rgba(250,250,249,.035); }
.layer-label > span, .hardware-title > span { color: var(--signal); font: 600 10px/1 Space Grotesk, sans-serif; }
.layer-label strong, .hardware-title strong { margin-top: auto; font-size: 17px; line-height: 1.25; }
.layer-label small, .hardware-title small { margin-top: 7px; color: var(--muted); font: 500 8px/1 Space Grotesk, sans-serif; letter-spacing: .12em; }
.layer-content { display: grid; gap: 1px; background: var(--line); }
.layer-content article { padding: 22px; background: var(--surface); }
.layer-content h4 { margin: 0 0 9px; font-size: 14px; }
.layer-content p { margin: 0; color: var(--muted); font-size: 11px; line-height: 1.55; }
.four-col { grid-template-columns: repeat(4, 1fr); }

.proprietary-layer { border-color: rgba(255,97,35,.58); }
.proprietary-layer .layer-label { border-color: rgba(255,97,35,.4); background: rgba(255,97,35,.08); }
.capability-grid { grid-template-columns: repeat(4, 1fr); }
.capability-grid .core { position: relative; min-height: 122px; background: #1d1a19; }
.core > span { position: absolute; right: 16px; top: 14px; color: rgba(255,97,35,.65); font: 600 18px/1 Space Grotesk, sans-serif; }
.platform-grid { grid-template-columns: repeat(3, 1fr); }

.fleet-layer { position: relative; }
.fleet-grid { grid-template-columns: 1.3fr 1fr 1fr 1fr; }
.fleet-grid .fleet-hub { background: #20201c; }
.optional-card { border: 1px dashed rgba(250,250,249,.28); }
.security-note { grid-column: 1 / -1; padding: 13px 16px; border-top: 1px solid rgba(126,183,255,.32); color: rgba(250,250,249,.72); background: rgba(126,183,255,.06); font-size: 11px; line-height: 1.55; }
.security-note strong { color: var(--blue); margin-right: 12px; }

.pool-row { margin: 0 18px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.pool { border: 1px solid var(--line); background: var(--surface); }
.pool header { min-height: 105px; padding: 20px; display: flex; flex-direction: column; border-bottom: 1px solid var(--line); }
.pool header strong { margin-top: 20px; font-size: 17px; }
.pool header small { margin-top: 7px; color: var(--muted); font-size: 10px; }
.shared-pool { border-color: rgba(255,97,35,.48); }
.dedicated-pool { border-color: rgba(250,207,159,.44); }
.batch-pool { border-color: rgba(126,183,255,.4); }
.pool-body { padding: 14px; }
.engine { padding: 15px; border: 1px solid var(--line); }
.engine b, .engine span, .engine-grid b, .engine-grid span { display: block; }
.engine b { font: 600 18px/1 Space Grotesk, sans-serif; }
.engine span { margin-top: 7px; color: var(--muted); font-size: 9px; line-height: 1.45; }
.engine-grid { margin-top: 8px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; }
.engine-grid div { min-height: 82px; padding: 12px; border: 1px solid var(--faint); background: var(--ink); }
.engine-grid b { font-size: 11px; line-height: 1.25; }
.engine-grid span { margin-top: 9px; color: var(--muted); font-size: 8px; }
.pool-body > p { margin: 16px 2px 2px; min-height: 48px; color: var(--muted); font-size: 10px; line-height: 1.6; }

.infra-grid { grid-template-columns: repeat(5, 1fr); }
.hardware-row { margin: 0 18px 18px; display: grid; grid-template-columns: 210px 1fr; border: 1px solid var(--line); }
.hardware-title { padding: 24px; display: flex; flex-direction: column; border-right: 1px solid var(--line); background: rgba(250,250,249,.035); }
.hardware-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 1px; background: var(--line); }
.hardware-grid article { min-height: 130px; padding: 20px; background: var(--surface); }
.hardware-grid b { display: block; margin-top: 28px; font-size: 14px; }
.hardware-grid p { margin: 7px 0 0; color: var(--muted); font-size: 10px; line-height: 1.45; }

body:not([data-view="all"]) .diagram-layer { opacity: .2; filter: saturate(.2); transition: 180ms ease; }
body[data-view="business"] [data-domain~="business"],
body[data-view="control"] [data-domain~="control"],
body[data-view="runtime"] [data-domain~="runtime"],
body[data-view="security"] [data-domain~="security"] { opacity: 1; filter: none; }

.flows, .boundaries, .decisions { border-top: 1px solid var(--line); }
.request-flow { display: grid; grid-template-columns: 1fr 40px 1fr 40px 1fr 40px 1fr; align-items: stretch; }
.request-flow article { min-height: 238px; padding: 26px; border: 1px solid var(--line); background: var(--surface); }
.request-flow article > span { color: var(--signal); font: 600 11px/1 Space Grotesk, sans-serif; }
.request-flow h3 { margin: 55px 0 12px; font-size: 19px; }
.request-flow p { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.65; }
.request-flow small { display: block; margin-top: 24px; color: var(--warm); font: 500 8px/1 Space Grotesk, sans-serif; letter-spacing: .12em; }
.request-flow > i { display: grid; place-items: center; color: var(--signal); font-style: normal; }
.request-flow .event-step { grid-column: 7; margin-top: 40px; border-color: rgba(250,207,159,.4); }
.request-flow .event-arrow { grid-column: 6; grid-row: 2; align-self: start; padding-top: 18px; }

.modes { border-top: 1px solid var(--line); }
.mode-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); }
.mode-grid article { position: relative; min-height: 430px; padding: 32px; background: var(--surface); }
.mode-index { position: absolute; right: 28px; top: 22px; color: rgba(255,97,35,.34); font: 600 72px/1 Space Grotesk, sans-serif; }
.mode-grid h3 { margin: 92px 0 18px; font-size: 28px; }
.mode-grid article > p { min-height: 92px; margin: 0; max-width: 390px; color: var(--muted); line-height: 1.72; }
.mode-grid dl { margin: 30px 0 0; border-top: 1px solid var(--line); }
.mode-grid dl div { padding: 12px 0; display: flex; justify-content: space-between; gap: 20px; border-bottom: 1px solid var(--faint); }
.mode-grid dt, .mode-grid dd { margin: 0; font-size: 11px; }
.mode-grid dt { color: var(--muted); }

.boundary-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: var(--line); }
.boundary-grid article { padding: 34px; background: var(--surface); }
.boundary-grid article.own { background: rgba(255,97,35,.07); }
.boundary-grid article > span { color: var(--signal); font-size: 11px; letter-spacing: .14em; }
.boundary-grid ul { margin: 34px 0 0; padding: 0; list-style: none; }
.boundary-grid li { padding: 17px 0 17px 24px; position: relative; border-top: 1px solid var(--faint); color: rgba(250,250,249,.78); line-height: 1.5; }
.boundary-grid li::before { content: "→"; position: absolute; left: 0; color: var(--signal); }

.decision-table { border-top: 1px solid var(--line); }
.decision-row { min-height: 78px; display: grid; grid-template-columns: 1.5fr 2fr 5fr; align-items: center; gap: 24px; border-bottom: 1px solid var(--line); }
.decision-row > span { color: var(--muted); font-size: 12px; }
.decision-row strong { font-size: 13px; }
.decision-row p { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.55; }
.decision-row.head { min-height: 48px; color: var(--signal); font-size: 9px; letter-spacing: .14em; text-transform: uppercase; }
.decision-row.head span { color: var(--signal); font-size: 9px; }

.download { margin-top: 40px; padding: 64px 0; display: grid; grid-template-columns: 7fr 5fr; gap: 60px; align-items: end; border-top: 2px solid var(--signal); }
.download h2 { margin: 18px 0 12px; font: 600 clamp(30px, 4vw, 56px)/1 Space Grotesk, "PingFang SC", sans-serif; letter-spacing: -.04em; }
.download p { margin: 0; color: var(--muted); line-height: 1.6; }
.download-actions { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 10px; }
.download-actions a { display: inline-flex; align-items: center; text-decoration: none; }

.footer { padding: 36px 0 46px; display: grid; grid-template-columns: 2fr 1fr 1fr auto; gap: 30px; align-items: end; border-top: 1px solid var(--line); }
.footer strong { font-size: 13px; letter-spacing: .12em; }
.footer span { color: var(--signal); font-size: 8px; letter-spacing: .15em; }
.footer p { margin: 8px 0 0; color: var(--muted); font-size: 10px; }
.footer a { color: var(--muted); font-size: 11px; text-decoration: none; }

@media (max-width: 1120px) {
  .layer, .hardware-row { grid-template-columns: 160px 1fr; }
  .capability-grid, .four-col { grid-template-columns: repeat(2, 1fr); }
  .platform-grid { grid-template-columns: repeat(2, 1fr); }
  .fleet-grid { grid-template-columns: repeat(2, 1fr); }
  .pool-row { grid-template-columns: 1fr; }
  .infra-grid, .hardware-grid { grid-template-columns: repeat(2, 1fr); }
  .request-flow { grid-template-columns: 1fr 28px 1fr; row-gap: 28px; }
  .request-flow > article:nth-of-type(3) { grid-column: 1; grid-row: 2; }
  .request-flow > article:nth-of-type(4) { grid-column: 3; grid-row: 2; }
  .request-flow > i:nth-of-type(3) { grid-column: 2; grid-row: 2; }
  .request-flow .event-step { grid-column: 3; grid-row: 3; margin-top: 0; }
  .request-flow .event-arrow { grid-column: 2; grid-row: 3; padding-top: 0; align-self: center; }
}

@media (max-width: 760px) {
  .shell { width: min(calc(100% - 28px), var(--max)); }
  .topbar { min-height: 66px; padding: 0 14px; }
  .topbar-meta span:first-child { display: none; }
  .hero { padding: 78px 0 62px; }
  .hero h1 { margin-bottom: 48px; }
  .hero-grid, .section-heading, .download { grid-template-columns: 1fr; gap: 32px; }
  .toolbar { align-items: flex-start; flex-direction: column; }
  .legend { justify-content: flex-start; }
  .architecture, .flows, .modes, .boundaries, .decisions { padding: 78px 0; }
  .section-heading { align-items: start; }
  .section-heading > div { display: block; }
  .section-heading > div > span { display: block; margin-bottom: 15px; }
  .actor-row { grid-template-columns: 1fr 1fr; }
  .layer, .hardware-row { grid-template-columns: 1fr; }
  .layer-label, .hardware-title { min-height: 102px; border-right: 0; border-bottom: 1px solid var(--line); }
  .layer-label strong, .hardware-title strong { margin-top: 24px; }
  .capability-grid, .four-col, .platform-grid, .fleet-grid, .infra-grid, .hardware-grid { grid-template-columns: 1fr; }
  .pool-row, .layer, .hardware-row { margin-left: 10px; margin-right: 10px; }
  .downlink.split, .downlink.triple { height: auto; padding: 14px; flex-direction: column; gap: 8px; }
  .mode-grid, .boundary-grid { grid-template-columns: 1fr; }
  .request-flow { display: block; }
  .request-flow > i { height: 32px; }
  .request-flow .event-step { margin-top: 0; }
  .decision-row { padding: 18px 0; grid-template-columns: 1fr; gap: 8px; }
  .decision-row.head { display: none; }
  .download-actions { justify-content: flex-start; flex-direction: column; }
  .download-actions a, .download-actions button { justify-content: center; }
  .footer { grid-template-columns: 1fr 1fr; }
}

@media print {
  @page { size: A3 landscape; margin: 12mm; }
  body { background: var(--ink); print-color-adjust: exact; -webkit-print-color-adjust: exact; }
  .topbar, .toolbar, .flows, .modes, .boundaries, .decisions, .download, .footer { display: none !important; }
  .hero { padding: 20px 0 30px; }
  .hero h1 { margin: 10px 0 20px; font-size: 46px; }
  .hero-grid { display: none; }
  .architecture { padding: 24px 0; }
  .section-heading { margin-bottom: 20px; }
  .diagram-frame { break-inside: avoid; }
}

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