:root {
  color-scheme: light;
  --bg: #f4f7f3;
  --bg-elevated: #fbfdf8;
  --surface: rgba(251, 253, 248, 0.88);
  --surface-solid: #fbfdf8;
  --surface-muted: #e7eee7;
  --text: #1d241f;
  --text-strong: #101511;
  --muted: #647069;
  --line: #cfd9ce;
  --line-strong: #9cad99;
  --accent: #0b6f5c;
  --accent-strong: #084f42;
  --accent-soft: #dceee6;
  --warn: #9c5f14;
  --code-bg: #252923;
  --code-text: #f2f5ec;
  --shadow: 0 24px 80px rgba(61, 50, 32, 0.13);
  --rail-width: 284px;
  --content-width: 1120px;
  --display-font: "Newsreader", Georgia, serif;
  --body-font: "Source Serif 4", Charter, Georgia, serif;
  --mono-font: "IBM Plex Mono", "SFMono-Regular", Consolas, monospace;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #111512;
  --bg-elevated: #171c18;
  --surface: rgba(23, 28, 24, 0.88);
  --surface-solid: #171c18;
  --surface-muted: #222920;
  --text: #e8e0d2;
  --text-strong: #fff8eb;
  --muted: #a7b0a6;
  --line: #354033;
  --line-strong: #53624f;
  --accent: #5dd2af;
  --accent-strong: #88e5c9;
  --accent-soft: #16382f;
  --warn: #e5ad59;
  --code-bg: #0c100d;
  --code-text: #f5efe3;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.34);
}

* {
  box-sizing: border-box;
}

html {
  background: var(--bg);
}

body {
  min-width: 320px;
  margin: 0;
  color: var(--text);
  background:
    linear-gradient(90deg, color-mix(in srgb, var(--line) 22%, transparent) 1px, transparent 1px) 0 0 / 44px 44px,
    linear-gradient(color-mix(in srgb, var(--line) 18%, transparent) 1px, transparent 1px) 0 0 / 44px 44px,
    linear-gradient(135deg, color-mix(in srgb, var(--accent-soft) 32%, transparent) 0%, transparent 34%, transparent 100%),
    var(--bg);
  font-family: var(--body-font);
  font-size: 18px;
  line-height: 1.66;
  text-rendering: optimizeLegibility;
}

a {
  color: var(--accent-strong);
  text-decoration-color: color-mix(in srgb, var(--accent) 45%, transparent);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--accent);
}

.site-shell {
  display: grid;
  grid-template-columns: var(--rail-width) minmax(0, 1fr);
  min-height: 100vh;
}

.site-rail {
  position: sticky;
  top: 0;
  height: 100vh;
  padding: 30px 24px;
  border-right: 1px solid var(--line);
  background: color-mix(in srgb, var(--surface-solid) 90%, transparent);
  backdrop-filter: blur(18px);
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.brand,
.mobile-brand {
  color: var(--text-strong);
  text-decoration: none;
}

.brand {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 12px;
  align-items: center;
}

.brand-mark {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  border: 1px solid var(--line-strong);
  background: var(--text-strong);
  color: var(--bg-elevated);
  font-family: var(--mono-font);
  font-size: 18px;
  font-weight: 600;
  box-shadow: 6px 6px 0 var(--accent-soft);
}

.brand-name,
.brand-kicker {
  display: block;
}

.brand-name {
  font-family: var(--display-font);
  font-size: 28px;
  font-weight: 650;
  line-height: 1;
}

.brand-kicker {
  margin-top: 3px;
  color: var(--muted);
  font-family: var(--mono-font);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0;
  text-transform: uppercase;
}

.doc-nav {
  display: grid;
  gap: 5px;
}

.doc-nav a {
  display: block;
  min-height: 40px;
  padding: 8px 10px;
  border-left: 2px solid transparent;
  color: var(--muted);
  font-family: var(--mono-font);
  font-size: 13px;
  line-height: 1.45;
  text-decoration: none;
  transition: background 160ms ease, border-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.doc-nav a:hover {
  border-left-color: var(--accent);
  background: var(--accent-soft);
  color: var(--text-strong);
  transform: translateX(2px);
}

.theme-toggle {
  margin-top: auto;
  width: 100%;
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--text);
  padding: 10px 12px;
  font-family: var(--mono-font);
  font-size: 12px;
  cursor: pointer;
  transition: border-color 160ms ease, transform 160ms ease, background 160ms ease;
}

.theme-toggle:hover {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.theme-toggle__track {
  position: relative;
  flex: 0 0 auto;
  width: 42px;
  height: 22px;
  border: 1px solid var(--line-strong);
  background: var(--surface-muted);
}

.theme-toggle__thumb {
  position: absolute;
  top: 3px;
  left: 3px;
  width: 14px;
  height: 14px;
  background: var(--accent);
  transition: transform 180ms ease;
}

:root[data-theme="dark"] .theme-toggle__thumb {
  transform: translateX(20px);
}

.doc-main {
  min-width: 0;
  padding: 32px clamp(18px, 5vw, 64px) 80px;
}

.doc-topbar {
  display: none;
}

.doc-content {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: clamp(28px, 5vw, 58px);
  border: 1px solid var(--line);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.doc-content > :first-child {
  margin-top: 0;
}

.doc-content h1,
.doc-content h2,
.doc-content h3 {
  color: var(--text-strong);
  font-family: var(--display-font);
  font-weight: 650;
  line-height: 1.06;
}

.doc-content h1 {
  max-width: 760px;
  margin: 0 0 22px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
  font-size: clamp(42px, 7vw, 76px);
}

.doc-content h2 {
  margin: 48px 0 14px;
  font-size: clamp(28px, 4vw, 42px);
}

.doc-content h3 {
  margin: 34px 0 10px;
  font-size: 25px;
}

.doc-content p,
.doc-content li {
  max-width: 76ch;
}

.doc-content p {
  margin: 0 0 18px;
}

.doc-content ul,
.doc-content ol {
  margin: 0 0 24px;
  padding-left: 1.15em;
}

.doc-content li + li {
  margin-top: 6px;
}

.doc-content hr {
  margin: 42px 0;
  border: 0;
  border-top: 1px solid var(--line);
}

.doc-content blockquote {
  margin: 28px 0;
  padding: 16px 20px;
  border-left: 4px solid var(--accent);
  background: var(--accent-soft);
}

.doc-content code {
  padding: 0.11em 0.32em;
  border: 1px solid color-mix(in srgb, var(--line) 70%, transparent);
  background: var(--surface-muted);
  color: var(--text-strong);
  font-family: var(--mono-font);
  font-size: 0.82em;
}

.doc-content pre {
  margin: 24px 0;
  padding: 18px;
  overflow-x: auto;
  border: 1px solid color-mix(in srgb, var(--line-strong) 55%, transparent);
  background: var(--code-bg);
  color: var(--code-text);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.05);
}

.doc-content pre code {
  padding: 0;
  border: 0;
  background: transparent;
  color: inherit;
  font-size: 13px;
  line-height: 1.6;
}

.doc-content table {
  display: block;
  width: 100%;
  margin: 28px 0;
  overflow-x: auto;
  border-collapse: collapse;
  font-size: 15px;
}

.doc-content th,
.doc-content td {
  min-width: 160px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  vertical-align: top;
}

.doc-content th {
  background: var(--surface-muted);
  color: var(--text-strong);
  font-family: var(--mono-font);
  font-size: 12px;
  font-weight: 600;
  text-align: left;
  text-transform: uppercase;
}

.doc-content tr:nth-child(even) td {
  background: color-mix(in srgb, var(--surface-muted) 38%, transparent);
}

.mermaid {
  position: relative;
  width: 100%;
  margin: 28px 0;
  padding: 18px;
  overflow-x: auto;
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--surface-solid) 82%, var(--accent-soft));
}

.mermaid::before {
  content: "Diagram";
  display: inline-block;
  margin: 0 0 10px;
  color: var(--muted);
  font-family: var(--mono-font);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
}

.mermaid svg {
  display: block;
  max-width: none;
  min-width: min(760px, 92vw);
  height: auto;
}

.mermaid--error {
  color: var(--code-text);
  background: var(--code-bg);
  font-family: var(--mono-font);
  font-size: 13px;
  line-height: 1.6;
  white-space: pre;
}

.phase-map {
  display: grid;
  gap: 12px;
  margin: 30px 0 36px;
}

.phase-row {
  display: grid;
  grid-template-columns: minmax(150px, 0.24fr) minmax(0, 1fr);
  border: 1px solid var(--line);
  background:
    linear-gradient(90deg, color-mix(in srgb, var(--accent-soft) 52%, transparent), transparent 42%),
    color-mix(in srgb, var(--surface-solid) 84%, transparent);
}

.phase-step {
  position: relative;
  display: grid;
  align-content: start;
  gap: 10px;
  min-height: 100%;
  padding: 18px 16px;
  border-right: 1px solid var(--line);
  background: color-mix(in srgb, var(--surface-muted) 48%, transparent);
}

.phase-step::after {
  content: "";
  position: absolute;
  right: -6px;
  top: 24px;
  width: 10px;
  height: 10px;
  border: 1px solid var(--line-strong);
  background: var(--accent);
  transform: rotate(45deg);
}

.phase-step span {
  display: inline-grid;
  width: 38px;
  height: 38px;
  place-items: center;
  border: 1px solid var(--line-strong);
  background: var(--text-strong);
  color: var(--bg-elevated);
  font-family: var(--mono-font);
  font-size: 13px;
  font-weight: 600;
}

.phase-step strong {
  color: var(--text-strong);
  font-family: var(--display-font);
  font-size: 25px;
  font-weight: 650;
  line-height: 1.05;
}

.phase-lanes {
  display: grid;
  grid-template-columns: minmax(150px, 0.86fr) minmax(190px, 1.08fr) minmax(240px, 1.35fr) minmax(220px, 1.22fr);
  gap: 1px;
  background: var(--line);
}

.phase-lane {
  min-width: 0;
  padding: 14px 16px 16px;
  background: color-mix(in srgb, var(--surface-solid) 88%, transparent);
}

.phase-lane--primary {
  background: color-mix(in srgb, var(--accent-soft) 58%, var(--surface-solid));
}

.phase-lane--gate {
  background: color-mix(in srgb, var(--surface-muted) 70%, var(--surface-solid));
}

.phase-lane h3 {
  margin: 0 0 8px;
  color: var(--muted);
  font-family: var(--mono-font);
  font-size: 11px;
  font-weight: 600;
  line-height: 1.2;
  text-transform: uppercase;
}

.phase-lane p {
  max-width: none;
  margin: 0;
  font-size: 15px;
  line-height: 1.46;
}

.phase-lane code {
  display: inline-block;
  margin: 2px 3px 2px 0;
  white-space: nowrap;
}

.home-lede {
  max-width: 780px;
  margin: -4px 0 30px;
  color: var(--muted);
  font-size: 22px;
  line-height: 1.45;
}

.doc-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 28px 0 36px;
}

.doc-card {
  min-height: 156px;
  padding: 18px;
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--surface-solid) 78%, transparent);
  text-decoration: none;
  transition: border-color 160ms ease, transform 160ms ease, box-shadow 160ms ease;
}

.doc-card:hover {
  border-color: var(--accent);
  box-shadow: 8px 8px 0 var(--accent-soft);
  transform: translate(-2px, -2px);
}

.doc-card strong {
  display: block;
  margin-bottom: 8px;
  color: var(--text-strong);
  font-family: var(--mono-font);
  font-size: 13px;
  text-transform: uppercase;
}

.doc-card span {
  display: block;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.45;
}

.value-grid,
.concept-strip {
  display: grid;
  gap: 12px;
  margin: 28px 0 34px;
}

.value-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.concept-strip {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.value-grid section,
.concept-strip section {
  min-width: 0;
  padding: 16px;
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--surface-solid) 76%, transparent);
}

.concept-strip section {
  background: color-mix(in srgb, var(--accent-soft) 46%, var(--surface-solid));
}

.value-grid strong,
.concept-strip strong {
  display: block;
  margin-bottom: 7px;
  color: var(--text-strong);
  font-family: var(--mono-font);
  font-size: 12px;
  font-weight: 600;
  line-height: 1.25;
  text-transform: uppercase;
}

.value-grid span,
.concept-strip span {
  display: block;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.42;
}

@media (max-width: 860px) {
  body {
    font-size: 17px;
  }

  .site-shell {
    display: block;
  }

  .site-rail {
    display: none;
  }

  .doc-main {
    padding: 0 14px 44px;
  }

  .doc-topbar {
    position: sticky;
    top: 0;
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    min-height: 62px;
    margin: 0 -14px 14px;
    padding: 10px 14px;
    border-bottom: 1px solid var(--line);
    background: color-mix(in srgb, var(--surface-solid) 90%, transparent);
    backdrop-filter: blur(16px);
  }

  .mobile-brand {
    font-family: var(--display-font);
    font-size: 28px;
    font-weight: 650;
  }

  .theme-toggle--compact {
    width: auto;
    margin: 0;
  }

  .doc-content {
    padding: 24px 18px 36px;
  }

  .doc-content h1 {
    font-size: clamp(38px, 14vw, 54px);
  }

  .doc-grid {
    grid-template-columns: 1fr;
  }

  .value-grid,
  .concept-strip {
    grid-template-columns: 1fr;
  }

  .mermaid {
    padding: 12px;
  }

  .mermaid::before {
    content: "Diagram - scroll sideways";
  }

  .phase-row {
    grid-template-columns: 1fr;
  }

  .phase-step {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .phase-step::after {
    right: auto;
    top: auto;
    bottom: -6px;
    left: 24px;
  }

  .phase-lanes {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}