:root {
  color-scheme: light;
  --paper: #f4f0e8;
  --paper-soft: #fbfaf6;
  --ink: #171511;
  --muted: #686158;
  --line: #d7cec0;
  --accent: #16745f;
  --accent-strong: #0f5a49;
  --warm: #b45a32;
  --blue: #2c5f91;
  --code-bg: #171511;
  --code-fg: #f8efe1;
  --shadow: 0 24px 70px rgb(23 21 17 / 14%);
  --header-height: 72px;
  --mono: "SFMono-Regular", "Cascadia Code", "Liberation Mono", Consolas, monospace;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --serif: ui-serif, Georgia, Cambria, "Times New Roman", serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  max-width: 100%;
  overflow-x: hidden;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

a {
  color: inherit;
  text-decoration-color: rgb(22 116 95 / 42%);
  text-underline-offset: 0.2em;
}

code {
  border-radius: 5px;
  background: rgb(23 21 17 / 7%);
  font-family: var(--mono);
  font-size: 0.92em;
  padding: 0.08rem 0.28rem;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: 1rem;
  z-index: 20;
  transform: translateY(-150%);
  border-radius: 6px;
  background: var(--ink);
  color: var(--paper-soft);
  padding: 0.7rem 0.9rem;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  min-height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  border-bottom: 1px solid rgb(23 21 17 / 10%);
  background: rgb(244 240 232 / 94%);
  backdrop-filter: blur(18px);
  padding: 0 5vw;
}

.brand {
  font-family: var(--mono);
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 0;
  text-decoration: none;
}

.top-nav {
  display: flex;
  gap: 1rem;
  font-size: 0.92rem;
}

.top-nav a {
  color: var(--muted);
  text-decoration: none;
}

.top-nav a:hover {
  color: var(--ink);
}

.hero {
  min-height: calc(100svh - var(--header-height));
  display: grid;
  grid-template-columns: minmax(0, 0.86fr) minmax(560px, 1.14fr);
  gap: clamp(2rem, 4.8vw, 5rem);
  align-items: center;
  border-bottom: 1px solid var(--line);
  padding: clamp(3rem, 6vw, 6.5rem) 5vw;
}

.hero-copy {
  max-width: 760px;
}

.eyebrow,
.section-kicker {
  margin: 0 0 1rem;
  color: var(--accent-strong);
  font-family: var(--mono);
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 980px;
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(3.4rem, 7vw, 7.8rem);
  font-weight: 760;
  letter-spacing: 0;
  line-height: 0.92;
}

.hero-lead {
  max-width: 700px;
  margin: 1.5rem 0 0;
  color: #403b34;
  font-size: clamp(1.06rem, 1.7vw, 1.3rem);
  line-height: 1.56;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 2rem;
}

.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--ink);
  border-radius: 6px;
  padding: 0.72rem 1rem;
  font-weight: 700;
  text-decoration: none;
  transition: transform 180ms ease, background 180ms ease, color 180ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button.primary {
  background: var(--ink);
  color: var(--paper-soft);
}

.button.secondary {
  color: var(--ink);
}

.hero-visual {
  min-height: 560px;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 1.4rem;
  overflow: hidden;
  border: 1px solid var(--ink);
  background:
    linear-gradient(90deg, rgb(23 21 17 / 6%) 1px, transparent 1px),
    linear-gradient(rgb(23 21 17 / 6%) 1px, transparent 1px),
    var(--paper-soft);
  background-size: 42px 42px;
  box-shadow: var(--shadow);
  padding: clamp(1rem, 2.2vw, 1.6rem);
}

.visual-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 1rem;
}

.visual-header span,
.stage-label {
  color: var(--accent-strong);
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
}

.visual-header strong {
  max-width: 250px;
  text-align: right;
}

.flow-diagram {
  display: grid;
  grid-template-columns: minmax(130px, 1fr) minmax(74px, 0.4fr) minmax(150px, 1.1fr) minmax(98px, 0.55fr) minmax(150px, 1.1fr);
  gap: 0.8rem;
  align-items: center;
}

.flow-card,
.callback-node {
  min-height: 150px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  border: 1px solid var(--ink);
  background: rgb(251 250 246 / 96%);
  padding: 1rem;
}

.flow-card.emphasized,
.callback-node {
  background: #eef5ef;
}

.flow-card strong,
.callback-node strong {
  display: block;
  margin-top: 0.45rem;
  font-size: 1.06rem;
  line-height: 1.22;
}

.flow-card small,
.callback-node small {
  display: block;
  margin-top: 0.7rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.76rem;
  line-height: 1.4;
}

.flow-link,
.callback-link {
  min-height: 78px;
  display: grid;
  place-items: center;
  position: relative;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.74rem;
  font-weight: 700;
  text-align: center;
  text-transform: uppercase;
}

.flow-link::before,
.callback-link::before {
  content: "";
  position: absolute;
  left: 0.15rem;
  right: 0.15rem;
  top: calc(50% + 1.1rem);
  height: 3px;
  background: var(--ink);
  z-index: 0;
}

.flow-link::after,
.callback-link::after {
  content: "";
  position: absolute;
  right: 0.1rem;
  top: calc(50% + 1.1rem - 8px);
  width: 18px;
  height: 16px;
  background: var(--ink);
  clip-path: polygon(0 0, 100% 50%, 0 100%);
  z-index: 0;
}

.flow-link span,
.callback-link span {
  position: relative;
  z-index: 1;
  max-width: 132px;
  border: 1px solid var(--line);
  background: var(--paper-soft);
  padding: 0.42rem 0.5rem;
  transform: translateY(-1rem);
}

.flow-link.soap {
  color: var(--accent-strong);
}

.flow-link.soap::before {
  background: var(--accent);
}

.flow-link.soap::after {
  background: var(--accent);
}

.callback-flow {
  display: grid;
  grid-template-columns: minmax(150px, 1fr) minmax(170px, 0.7fr) minmax(150px, 1fr);
  gap: 1rem;
  align-items: center;
  border-top: 1px solid var(--line);
  padding-top: 1.2rem;
}

.callback-node {
  min-height: 128px;
  border-color: var(--warm);
  background: #fff4ec;
}

.callback-link {
  color: var(--warm);
}

.callback-link::before {
  background: var(--warm);
}

.callback-link::after {
  background: var(--warm);
}

.disclaimer {
  border-bottom: 1px solid var(--line);
  background: #fff4ec;
  color: #42352c;
  padding: 1rem 5vw;
  font-size: 0.98rem;
}

.disclaimer strong {
  color: var(--warm);
}

.intro-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-bottom: 1px solid var(--line);
  background: var(--paper-soft);
}

.intro-strip div {
  border-right: 1px solid var(--line);
  padding: 1.2rem 5vw;
}

.intro-strip span {
  display: block;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.76rem;
  text-transform: uppercase;
}

.intro-strip strong {
  display: block;
  margin-top: 0.25rem;
  line-height: 1.3;
}

.page-shell {
  width: 100%;
  max-width: 1380px;
  display: grid;
  grid-template-columns: 250px minmax(0, 980px);
  gap: clamp(2rem, 6vw, 5rem);
  align-items: start;
  margin: 0 auto;
  padding: clamp(3rem, 7vw, 7rem) 5vw;
}

.toc {
  position: sticky;
  top: calc(var(--header-height) + 2rem);
  display: grid;
  gap: 0.35rem;
  font-size: 0.92rem;
}

.toc p {
  margin: 0 0 0.6rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
}

.toc a {
  display: block;
  border-left: 2px solid transparent;
  color: var(--muted);
  padding: 0.28rem 0 0.28rem 0.8rem;
  text-decoration: none;
}

.toc a.active,
.toc a:hover {
  border-left-color: var(--accent);
  color: var(--ink);
}

.article {
  min-width: 0;
  display: grid;
  gap: clamp(3rem, 6vw, 5.5rem);
}

.article-section {
  min-width: 0;
  scroll-margin-top: calc(var(--header-height) + 1.5rem);
}

.article-section h2 {
  margin: 0 0 1.1rem;
  font-family: var(--serif);
  font-size: clamp(2.1rem, 4vw, 4rem);
  letter-spacing: 0;
  line-height: 1.02;
}

.article-section h3 {
  margin: 0 0 0.7rem;
  font-size: 1.1rem;
}

.article-section p {
  margin: 1rem 0 0;
  color: #3f3931;
  font-size: 1.04rem;
}

.call-lanes,
.trust-grid,
.sequence,
.soap-header-diagram,
.endpoint-list,
.final-links,
.log-grid {
  margin-top: 1.6rem;
}

.call-lanes {
  min-width: 0;
  max-width: 100%;
  display: grid;
  gap: 0.85rem;
}

.lane {
  min-width: 0;
  display: grid;
  grid-template-columns: minmax(145px, 1fr) minmax(180px, 1.15fr) minmax(145px, 1fr);
  gap: 1rem;
  align-items: center;
  border: 1px solid var(--ink);
  background: var(--paper-soft);
  padding: 1rem;
}

.lane-party {
  min-width: 0;
  min-height: 80px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  background: white;
  font-weight: 800;
  text-align: center;
}

.lane-party.target {
  background: #eef5ef;
}

.lane-protocol {
  min-width: 0;
  min-height: 64px;
  display: grid;
  place-items: center;
  position: relative;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.82rem;
  font-weight: 700;
  text-align: center;
  text-transform: uppercase;
}

.lane-protocol::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 3px;
  background: var(--ink);
  z-index: 0;
}

.lane-protocol::after {
  content: "";
  position: absolute;
  right: 0;
  top: calc(50% - 8px);
  width: 18px;
  height: 16px;
  background: var(--ink);
  clip-path: polygon(0 0, 100% 50%, 0 100%);
  z-index: 0;
}

.lane-protocol span {
  position: relative;
  z-index: 1;
  max-width: min(100%, 230px);
  border: 1px solid var(--line);
  background: var(--paper-soft);
  padding: 0.45rem 0.55rem;
  overflow-wrap: anywhere;
}

.lane.strong .lane-protocol,
.lane.strong .lane-party.target {
  color: var(--accent-strong);
}

.lane.strong .lane-protocol::before,
.lane.strong .lane-protocol::after {
  background: var(--accent);
}

.lane.callback .lane-protocol,
.lane.callback .lane-party.target {
  color: var(--warm);
}

.lane.callback .lane-protocol::before,
.lane.callback .lane-protocol::after {
  background: var(--warm);
}

.code-card {
  min-width: 0;
  max-width: 100%;
  overflow: hidden;
  border: 1px solid var(--ink);
  background: var(--code-bg);
  box-shadow: 0 16px 48px rgb(23 21 17 / 10%);
  margin-top: 1.6rem;
}

.code-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  border-bottom: 1px solid rgb(247 239 226 / 18%);
  color: rgb(247 239 226 / 74%);
  font-family: var(--mono);
  font-size: 0.78rem;
  padding: 0.7rem 0.85rem;
}

.code-title button {
  border: 1px solid rgb(247 239 226 / 34%);
  border-radius: 5px;
  background: transparent;
  color: var(--code-fg);
  cursor: pointer;
  font: inherit;
  padding: 0.35rem 0.55rem;
}

.code-title button:hover {
  border-color: var(--code-fg);
}

pre {
  max-width: 100%;
  max-height: min(680px, 72vh);
  overflow: auto;
  margin: 0;
  color: var(--code-fg);
  font-family: var(--mono);
  font-size: 0.88rem;
  line-height: 1.55;
  padding: 1.1rem;
  tab-size: 4;
}

pre code {
  display: block;
  min-width: max-content;
  border-radius: 0;
  background: transparent;
  color: inherit;
  font-size: inherit;
  padding: 0;
  white-space: pre;
}

.tok-keyword,
.tok-method {
  color: #79d2ff;
}

.tok-annotation,
.tok-property {
  color: #9be38f;
}

.tok-string,
.tok-attr-value {
  color: #ffd38a;
}

.tok-comment,
.tok-muted {
  color: #8e938a;
}

.tok-number,
.tok-status {
  color: #f79c7b;
}

.tok-tag,
.tok-level {
  color: #f1a3ff;
}

.tok-attr,
.tok-url {
  color: #8fd3c7;
}

.tok-time {
  color: #c9b7ff;
}

.tok-http {
  color: #8fd3c7;
  font-weight: 700;
}

.trust-grid {
  min-width: 0;
  max-width: 100%;
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(190px, 0.7fr) minmax(220px, 1fr);
  gap: 1rem;
  align-items: stretch;
}

.trust-service,
.trust-exchange {
  border: 1px solid var(--ink);
  background: var(--paper-soft);
  padding: 1.2rem;
}

.trust-service p {
  margin: 0.8rem 0 0;
}

.trust-service strong,
.trust-service span {
  display: block;
}

.trust-service span {
  color: var(--muted);
  font-size: 0.9rem;
}

.trust-exchange {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1rem;
  color: var(--accent-strong);
  font-family: var(--mono);
  font-size: 0.8rem;
  font-weight: 700;
  text-align: center;
  text-transform: uppercase;
}

.soap-header-diagram {
  border: 1px solid var(--ink);
  background: var(--paper-soft);
  font-family: var(--mono);
  font-size: 0.88rem;
  padding: 1rem;
}

.xml-line {
  border-left: 2px solid transparent;
  padding: 0.3rem 0.5rem;
}

.xml-line.level-1 {
  margin-left: 1rem;
  border-left-color: var(--accent);
}

.xml-line.level-2 {
  margin-left: 2rem;
  border-left-color: var(--warm);
}

.xml-line.level-3 {
  margin-left: 3rem;
  border-left-color: var(--line);
  color: var(--muted);
}

.sequence {
  min-width: 0;
  max-width: 100%;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.sequence div {
  min-height: 118px;
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 1rem;
  align-items: start;
  border: 1px solid var(--ink);
  background: var(--paper-soft);
  padding: 1rem;
}

.sequence span {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border: 1px solid var(--ink);
  border-radius: 50%;
  font-family: var(--mono);
  font-weight: 700;
}

.sequence p {
  margin: 0;
}

.log-grid {
  min-width: 0;
  max-width: 100%;
  display: grid;
  gap: 1.4rem;
}

.log-card pre {
  max-height: 620px;
}

.endpoint-list,
.final-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.endpoint-list a,
.final-links a {
  border: 1px solid var(--ink);
  border-radius: 6px;
  background: var(--paper-soft);
  font-weight: 700;
  padding: 0.65rem 0.8rem;
  text-decoration: none;
}

.endpoint-list a:hover,
.final-links a:hover {
  background: var(--ink);
  color: var(--paper-soft);
}

.site-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.92rem;
  padding: 2rem 5vw;
}

.site-footer p {
  margin: 0;
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 500ms ease, transform 500ms ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1180px) {
  .hero {
    grid-template-columns: 1fr;
  }

  .hero-visual {
    min-height: auto;
  }

  .intro-strip {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-shell {
    grid-template-columns: 1fr;
  }

  .toc {
    position: static;
    display: flex;
    overflow-x: auto;
    border-bottom: 1px solid var(--line);
    padding-bottom: 0.8rem;
  }

  .toc p,
  .toc a {
    flex: 0 0 auto;
  }

  .toc p {
    margin: 0;
    padding: 0.28rem 0.8rem 0.28rem 0;
  }

  .toc a {
    border-left: 0;
    border-bottom: 2px solid transparent;
    padding: 0.28rem 0.4rem;
  }

  .toc a.active,
  .toc a:hover {
    border-bottom-color: var(--accent);
  }
}

@media (max-width: 820px) {
  :root {
    --header-height: 64px;
  }

  .site-header {
    padding: 0 1rem;
  }

  .top-nav {
    gap: 0.7rem;
    font-size: 0.84rem;
  }

  .hero {
    padding: 2.4rem 1rem 3rem;
  }

  .hero h1 {
    font-size: clamp(3rem, 15vw, 4.8rem);
  }

  .visual-header {
    display: grid;
  }

  .visual-header strong {
    max-width: none;
    text-align: left;
  }

  .flow-diagram,
  .callback-flow,
  .lane,
  .trust-grid,
  .sequence {
    grid-template-columns: 1fr;
  }

  .flow-link,
  .callback-link,
  .lane-protocol {
    min-height: 56px;
  }

  .flow-link::before,
  .callback-link::before,
  .lane-protocol::before {
    left: 50%;
    right: auto;
    top: 0;
    bottom: 0;
    width: 2px;
    height: auto;
  }

  .flow-link::after,
  .callback-link::after,
  .lane-protocol::after {
    right: calc(50% - 7px);
    top: auto;
    bottom: 0;
    width: 14px;
    height: 16px;
    border: 0;
    clip-path: polygon(0 0, 100% 0, 50% 100%);
  }

  .flow-link.soap::after {
    background: var(--accent);
  }

  .callback-link::after {
    background: var(--warm);
  }

  .lane-protocol {
    background:
      linear-gradient(var(--paper-soft), var(--paper-soft)) center / 12rem 2.2rem no-repeat;
  }

  .intro-strip {
    grid-template-columns: 1fr;
  }

  .intro-strip div {
    padding: 1rem;
  }

  .page-shell {
    padding: 2.5rem 1rem;
  }

  .toc {
    width: 100%;
    max-width: 100%;
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.15rem;
    overflow: visible;
    border-bottom: 1px solid var(--line);
    padding-bottom: 1rem;
  }

  .toc p,
  .toc a {
    min-width: 0;
    flex: initial;
  }

  .toc p {
    margin: 0 0 0.45rem;
    padding: 0;
  }

  .toc a {
    width: 100%;
    border-left: 2px solid transparent;
    border-bottom: 0;
    padding: 0.42rem 0 0.42rem 0.75rem;
    white-space: normal;
    overflow-wrap: anywhere;
  }

  .toc a.active,
  .toc a:hover {
    border-left-color: var(--accent);
    border-bottom-color: transparent;
  }

  .code-title {
    align-items: flex-start;
    flex-direction: column;
  }

  pre {
    font-size: 0.8rem;
  }

  .xml-line.level-1,
  .xml-line.level-2,
  .xml-line.level-3 {
    margin-left: 0.5rem;
  }
}

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

  .reveal {
    opacity: 1;
    transform: none;
  }
}

@media print {
  .site-header,
  .toc,
  .hero-actions,
  .code-title button,
  .site-footer {
    display: none;
  }

  body {
    background: white;
    color: black;
  }

  .hero,
  .page-shell {
    display: block;
    padding: 0;
  }

  .hero-visual,
  .intro-strip,
  .code-card,
  .call-lanes,
  .trust-grid,
  .sequence,
  .soap-header-diagram {
    box-shadow: none;
    break-inside: avoid;
  }
}