:root {
  --navy: #2C3E50;
  --gray: #ECF0F1;
  --white: #FFFFFF;
  --turquoise: #18BC9C;
  --turquoise-ink: #0D6D5A;
  --amber: #F39C12;
  --amber-ink: #7A4E00;
  --border: rgba(44, 62, 80, 0.16);
  --border-strong: rgba(44, 62, 80, 0.28);
  --font-sans: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --shadow-flat: 0 1px 0 rgba(44, 62, 80, 0.18);
  --container: 1180px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--gray);
  color: var(--navy);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

::selection {
  background: var(--navy);
  color: var(--gray);
}

::-webkit-scrollbar { width: 12px; height: 12px; }
::-webkit-scrollbar-track { background: var(--gray); }
::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border: 3px solid var(--gray);
  border-radius: var(--radius-lg);
}
::-webkit-scrollbar-thumb:hover { background: var(--navy); }

:focus-visible {
  outline: 2px solid var(--navy);
  outline-offset: 2px;
  border-radius: 2px;
}

a {
  color: var(--navy);
  text-underline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--navy);
  color: var(--white);
  padding: 0.75rem 1.25rem;
  z-index: 100;
  border-radius: 0 0 var(--radius-sm) 0;
}
.skip-link:focus {
  left: 0;
}

/* Masthead */

.masthead {
  background: var(--gray);
  border-bottom: 1px solid var(--border-strong);
  position: sticky;
  top: 0;
  z-index: 20;
}

.masthead-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0.85rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.6rem 1rem;
}

.wordmark {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  color: var(--navy);
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
}

.masthead-tags {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.tag {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  padding: 0.3rem 0.55rem;
  border-radius: var(--radius-sm);
  line-height: 1.4;
  white-space: nowrap;
}

.tag--wide {
  text-transform: none;
  letter-spacing: 0;
  font-size: 0.75rem;
  white-space: normal;
}

.tag--neutral {
  background: var(--white);
  color: var(--navy);
  border: 1px solid var(--border-strong);
}

.tag--icon {
  background: var(--white);
  color: var(--navy);
  border: 1px solid var(--border-strong);
  gap: 0.35rem;
  text-decoration: none;
  cursor: pointer;
}

.tag--icon:hover {
  background: var(--navy);
  color: var(--white);
}

.tag--icon svg { flex-shrink: 0; }

.tag--turquoise {
  background: var(--turquoise);
  color: var(--navy);
  border: 1px solid var(--turquoise-ink);
}

.tag--amber {
  background: var(--amber);
  color: var(--navy);
  border: 1px solid var(--amber-ink);
}

/* Nav tabs */

.site-nav {
  background: var(--white);
  border-bottom: 1px solid var(--border-strong);
}

.site-nav ul {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.25rem;
  list-style: none;
  display: flex;
  gap: 0.25rem;
  overflow-x: auto;
  scrollbar-width: none;
}
.site-nav ul::-webkit-scrollbar { display: none; }

.site-nav a {
  display: inline-block;
  padding: 0.85rem 0.9rem;
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
  color: var(--navy);
  opacity: 0.8;
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}

.site-nav a:hover { opacity: 1; }

.site-nav a[aria-current="page"] {
  opacity: 1;
  border-bottom-color: var(--navy);
}

/* Layout */

.section-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 3.5rem 1.25rem;
}

.section-inner--prose {
  max-width: 74ch;
}

.section + .section {
  border-top: 1px solid var(--border);
}

.hero {
  max-width: var(--container);
  margin: 0 auto;
  padding: 3.25rem 1.25rem 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
}

.thesis {
  font-size: clamp(1.5rem, 1.05rem + 1.6vw, 2.35rem);
  font-weight: 600;
  line-height: 1.32;
  letter-spacing: -0.015em;
  max-width: 22ch;
  margin: 0;
}

.hero-mark {
  flex-shrink: 0;
  width: clamp(140px, 16vw, 200px);
  height: auto;
}

h2 {
  font-size: clamp(1.35rem, 1.15rem + 0.7vw, 1.75rem);
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 1.25rem;
}

h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 0 0 0.35rem;
}

p { margin: 0 0 1rem; }
p:last-child { margin-bottom: 0; }

.protocol-chain {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 500;
  background: var(--white);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1rem 1.1rem;
  line-height: 1.7;
  box-shadow: var(--shadow-flat);
}

/* Stage list */

.stage-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.stage-list li {
  display: grid;
  grid-template-columns: 3rem 1fr;
  gap: 1.25rem;
  padding: 1.5rem 0;
  border-top: 1px solid var(--border);
}

.stage-list li:first-child { border-top: none; }

.stage-list-num {
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--navy);
  opacity: 0.8;
  font-size: 1rem;
  padding-top: 0.1rem;
}

.stage-output {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--navy);
  opacity: 0.8;
  margin-bottom: 0 !important;
}

/* Boundary */

.section--boundary {
  background: var(--white);
}

.boundary-intro {
  max-width: 74ch;
}

.boundary-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-top: 1.75rem;
}

.boundary-block {
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.4rem 1.4rem;
  background: var(--gray);
  box-shadow: var(--shadow-flat);
}

.boundary-block ul {
  margin: 0.9rem 0 0;
  padding-left: 1.15rem;
}

.boundary-block li {
  margin-bottom: 0.55rem;
  font-size: 0.95rem;
}
.boundary-block li:last-child { margin-bottom: 0; }

.boundary-block--in li::marker { color: var(--turquoise-ink); }
.boundary-block--out li::marker { color: var(--amber-ink); }

.boundary-footer {
  max-width: 74ch;
  margin-top: 1.75rem;
  font-size: 0.92rem;
  opacity: 0.85;
}

/* Record list */

.record-list {
  columns: 2;
  column-gap: 2rem;
  padding-left: 1.15rem;
  margin: 0 0 1rem;
}
.record-list li { margin-bottom: 0.5rem; break-inside: avoid; }

/* Get it */

.section--get {
  background: var(--navy);
  color: var(--gray);
}

.section--get h2 { color: var(--white); }

.get-intro {
  opacity: 0.75;
  max-width: 60ch;
}

.get-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1px;
  background: rgba(236, 240, 241, 0.16);
  border: 1px solid rgba(236, 240, 241, 0.16);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-top: 1.75rem;
}

.get-card {
  background: var(--navy);
  padding: 1.4rem 1.4rem 1.6rem;
}

.get-card .tag--neutral {
  background: var(--gray);
  color: var(--navy);
  border-color: var(--gray);
}

.get-card p {
  margin: 0.75rem 0 0;
  font-size: 0.92rem;
  opacity: 0.85;
}

.get-card code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: rgba(236, 240, 241, 0.1);
  padding: 0.1em 0.35em;
  border-radius: 3px;
}

.get-link {
  margin-top: 1.5rem;
}

.get-link a {
  color: var(--white);
  font-weight: 600;
  font-size: 0.92rem;
  text-decoration: underline;
}

/* Docs page */

.page-intro {
  max-width: 74ch;
}

.page-intro h1 {
  font-size: clamp(1.6rem, 1.3rem + 1vw, 2.15rem);
  font-weight: 700;
  letter-spacing: -0.015em;
  margin: 0 0 0.75rem;
}

.file-tree {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.85;
  background: var(--white);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1.1rem 1.3rem;
  box-shadow: var(--shadow-flat);
  white-space: pre;
  overflow-x: auto;
}

.file-tree .path-note {
  font-family: var(--font-sans);
  opacity: 0.8;
}

.file-tree-note {
  margin-top: 1.25rem;
}

.install-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 1.75rem;
}

.install-card {
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  background: var(--gray);
  box-shadow: var(--shadow-flat);
  padding: 1.4rem 1.5rem 1.6rem;
}

.install-card h3 {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 1rem;
}

.install-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: step;
}

.install-steps li {
  counter-increment: step;
  display: grid;
  grid-template-columns: 1.5rem 1fr;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  font-size: 0.92rem;
}
.install-steps li:last-child { margin-bottom: 0; }

.install-steps li > span {
  min-width: 0;
}

.install-steps li::before {
  content: counter(step);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--navy);
  background: var(--white);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  width: 1.5rem;
  height: 1.5rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.install-steps code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--white);
  border: 1px solid var(--border);
  padding: 0.1em 0.35em;
  border-radius: 3px;
  overflow-wrap: break-word;
}

.install-steps code.cmd {
  display: block;
  margin-top: 0.5rem;
  padding: 0.55rem 0.7rem;
  white-space: pre;
  overflow-x: auto;
}

/* Example page */

.section--seed {
  background: var(--white);
}

.seed-quote {
  font-family: var(--font-sans);
  font-size: clamp(1.15rem, 1rem + 0.7vw, 1.5rem);
  font-weight: 500;
  font-style: italic;
  line-height: 1.5;
  max-width: 60ch;
  background: var(--gray);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  box-shadow: var(--shadow-flat);
  margin: 0;
}

.transcript {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.turn {
  background: var(--gray);
  padding: 1.1rem 1.4rem 1.25rem;
}

.turn--agent {
  background: var(--white);
}

.turn-role {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--navy);
  opacity: 0.8;
  margin-bottom: 0.5rem;
}

.turn p {
  max-width: 74ch;
}

.turn p:last-child {
  margin-bottom: 0;
}

.turn ul {
  max-width: 74ch;
  margin: 0.75rem 0 1rem;
  padding-left: 1.15rem;
}

.turn li {
  margin-bottom: 0.4rem;
}

.turn-aside {
  margin-top: 0.75rem;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.6rem;
}

.section--record {
  background: var(--white);
}

.record-yaml {
  margin: 1.75rem 0 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.7;
  background: var(--gray);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1.1rem 1.3rem;
  box-shadow: var(--shadow-flat);
  overflow-x: auto;
  max-height: 32rem;
  overflow-y: auto;
}

.record-yaml code {
  white-space: pre;
}

/* Footer */

.site-footer {
  border-top: 1px solid var(--border-strong);
  padding: 1.5rem 1.25rem 2.25rem;
  text-align: center;
}

.site-footer p {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  opacity: 0.8;
}

/* Responsive */

@media (max-width: 720px) {
  .boundary-grid { grid-template-columns: 1fr; }
  .record-list { columns: 1; }
  .stage-list li { grid-template-columns: 2.25rem 1fr; gap: 0.9rem; }
  .section-inner { padding: 2.5rem 1.1rem; }
  .hero {
    padding: 2.25rem 1.1rem 2rem;
    flex-direction: column-reverse;
    align-items: flex-start;
    gap: 1.5rem;
  }
  .hero-mark { width: 104px; }
  .masthead-inner { flex-direction: column; align-items: flex-start; }
  .masthead-tags { width: 100%; flex-direction: column; align-items: flex-start; }
}

@media (min-width: 1400px) {
  :root { --container: 1280px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}