/* Arsia Protocol website. Colours come from tokens.css (brand manual v1.0).
   Layout and motion follow the Arsia Labs website so the two read as one family. */

:root {
  --wrap: 1240px;
  --gutter: 48px;
  --nav-h: 64px;
  --panel-border: rgba(233, 238, 241, .14);
  --panel-muted: rgba(233, 238, 241, .68);
  --panel-faint: rgba(233, 238, 241, .08);
  --ease: cubic-bezier(.22, .61, .36, 1);
  --lockup-core: var(--accent);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 16px); background: var(--bg); }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 400 17px/1.65 var(--font-body);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
h1, h2, h3, h4, p, dl, dd, ol, ul, figure, blockquote { margin: 0; }
ol, ul { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; cursor: pointer; }
code, pre, kbd { font-family: var(--font-mono); }
[hidden] { display: none !important; }
:focus-visible { outline: 2px solid var(--accent-surface); outline-offset: 3px; }
#main:focus { outline: none; }

.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.skip-link { position: absolute; left: 16px; top: 0; z-index: 100; transform: translateY(-120%); background: var(--fg); color: var(--bg); padding: 12px 16px; }
.skip-link:focus { transform: none; }

.wrap { max-width: calc(var(--wrap) + 2 * var(--gutter)); margin: 0 auto; padding: 0 var(--gutter); }

/* ── Type ─────────────────────────────────────────────── */
h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 700; letter-spacing: -.025em; line-height: 1.1; text-wrap: balance; }
.eyebrow { font: 500 12px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--accent); }
.eyebrow-panel { color: var(--accent-on-panel); }
.display { font-size: clamp(40px, 6vw, 80px); line-height: 1.03; letter-spacing: -.035em; }
.section-lede { font-size: clamp(19px, 1.7vw, 24px); line-height: 1.45; color: var(--muted); max-width: 680px; text-wrap: pretty; }

/* ── Buttons and links ────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  min-height: 48px; padding: 14px 20px;
  border: 1px solid transparent; border-radius: 0;
  font: 500 13px/1.2 var(--font-mono); letter-spacing: .04em; text-transform: uppercase;
  transition: background-color .2s var(--ease), border-color .2s var(--ease), color .2s var(--ease);
}
.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--bg); }
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
.btn-primary:disabled { opacity: .6; cursor: wait; }
.btn-secondary { background: transparent; border-color: var(--fg); color: var(--fg); }
.btn-secondary:hover { border-color: var(--accent-surface); }
.btn-panel { background: var(--accent-on-panel); border-color: var(--accent-on-panel); color: #0D1114; }
.btn-panel:hover { background: #ABBCE9; border-color: #ABBCE9; }
.btn-panel-outline { background: transparent; border-color: var(--panel-fg); color: var(--panel-fg); }
.btn-panel-outline:hover { border-color: var(--accent-on-panel); }
.link { display: inline-flex; align-items: center; gap: 6px; font-size: 17px; color: var(--accent); border-bottom: 1px solid transparent; transition: border-color .2s var(--ease); }
.link:hover { border-bottom-color: currentColor; }
.link-panel { color: var(--accent-on-panel); }

/* ── Navigation ───────────────────────────────────────── */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 84%, transparent);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--border);
  transition: background-color .35s var(--ease), border-color .35s var(--ease);
}
.nav-inner { height: var(--nav-h); display: flex; align-items: center; gap: 28px; }
.nav-logo { display: block; padding: 14px 0; color: var(--fg); line-height: 0; flex-shrink: 0; }
.nav-logo svg { width: 191.08px; height: 27.96px; display: block; }
.nav-links { display: flex; gap: 26px; margin-left: auto; font-size: 14px; }
.nav-links a { color: var(--muted); padding: 6px 0; transition: color .2s var(--ease); }
.nav-links a:hover, .nav-links a[aria-current] { color: var(--fg); }
.nav-tools { display: flex; align-items: center; gap: 8px; }
.nav-cta { font: 500 12px/1 var(--font-mono); letter-spacing: .06em; text-transform: uppercase; padding: 10px 14px; background: var(--accent); color: var(--bg); transition: background-color .2s var(--ease); white-space: nowrap; }
.nav-cta:hover { background: var(--accent-hover); }
.nav-menu { display: none; background: none; border: 0; padding: 10px 0; min-height: 44px; font: 500 12px/1 var(--font-mono); letter-spacing: .06em; text-transform: uppercase; }
.mobile-nav { display: none; }
.icon-btn { display: inline-flex; align-items: center; justify-content: center; width: 40px; height: 40px; padding: 0; background: none; border: 1px solid transparent; color: var(--muted); transition: color .2s var(--ease), border-color .2s var(--ease); }
.icon-btn:hover { color: var(--fg); border-color: var(--border); }
.icon-btn svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
html[data-theme="dark"] .theme-toggle .icon-moon, html:not([data-theme="dark"]) .theme-toggle .icon-sun { display: none; }

/* Navigation over dark bands */
.nav[data-tone="dark"] { background: color-mix(in srgb, var(--panel) 96%, transparent); border-bottom-color: var(--panel-border); --lockup-core: var(--accent-on-panel); }
.nav[data-tone="dark"] .nav-logo, .nav[data-tone="dark"] .nav-menu { color: var(--panel-fg); }
.nav[data-tone="dark"] .nav-links a { color: var(--panel-muted); }
.nav[data-tone="dark"] .nav-links a:hover, .nav[data-tone="dark"] .nav-links a[aria-current] { color: var(--panel-fg); }
.nav[data-tone="dark"] .nav-cta { background: var(--accent-on-panel); color: #0D1114; }
.nav[data-tone="dark"] .icon-btn { color: var(--panel-muted); }
.nav[data-tone="dark"] .icon-btn:hover { color: var(--panel-fg); border-color: var(--panel-border); }
.nav[data-tone="dark"] .mobile-nav { border-top-color: var(--panel-border); }
.nav[data-tone="dark"] .mobile-nav a { color: var(--panel-fg); border-bottom-color: var(--panel-border); }

/* ── Hero ─────────────────────────────────────────────── */
.hero {
  padding: clamp(72px, 8vw, 120px) 0 0; text-align: center;
  background: radial-gradient(ellipse 70% 55% at 50% 0%, rgba(147, 169, 224, .16), transparent 70%), var(--panel);
  color: var(--panel-fg);
}
.hero-status { display: inline-flex; align-items: center; gap: 12px; padding: 8px 14px; border: 1px solid var(--panel-border); font: 500 11px/1.3 var(--font-mono); letter-spacing: .14em; text-transform: uppercase; color: var(--panel-muted); }
.status-dot { width: 7px; height: 7px; background: var(--accent-on-panel); animation: pulse 1.8s var(--ease) infinite; }
.hero h1 { margin-top: 36px; font-size: clamp(44px, 6.4vw, 92px); line-height: 1.02; letter-spacing: -.04em; }
.hero h1 em { font-style: normal; color: var(--accent-on-panel); }
.hero-lede { margin: 32px auto 0; max-width: 740px; font-size: clamp(19px, 1.7vw, 24px); line-height: 1.45; color: var(--panel-muted); text-wrap: pretty; }
.hero-actions { margin-top: 44px; display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.install { margin: 28px auto 0; display: inline-flex; align-items: center; gap: 16px; padding: 10px 10px 10px 18px; border: 1px solid var(--panel-border); font: 400 14px/1.4 var(--font-mono); color: var(--panel-fg); }
.install .prompt { color: var(--accent-on-panel); }
.hero-visual { margin: clamp(32px, 4vw, 56px) 0 0; }
.hero-visual canvas { display: block; width: 100%; height: clamp(320px, 34vw, 500px); }

/* Metrics strip under the hero */
.metrics { background: var(--panel); color: var(--panel-fg); border-top: 1px solid var(--panel-border); }
.metrics ul { display: grid; grid-template-columns: repeat(4, 1fr); }
.metrics li { padding: 28px 0 32px; text-align: center; }
.metrics li + li { border-left: 1px solid var(--panel-border); }
.metric-num { display: block; font: 700 clamp(32px, 3.4vw, 48px)/1 var(--font-display); letter-spacing: -.03em; font-variant-numeric: tabular-nums; }
.metric-label { display: block; margin-top: 10px; font: 500 11px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--panel-muted); }

/* ── Sections ─────────────────────────────────────────── */
.section { padding: clamp(88px, 11vw, 152px) 0; }
.section + .section { border-top: 1px solid var(--border); }
.section-head { margin-bottom: clamp(48px, 6vw, 80px); }
.section-head .eyebrow + h2 { margin-top: 18px; }
.section-head h2 + .section-lede { margin-top: 24px; }
.section-head.center { text-align: center; }
.section-head.center .section-lede { margin-left: auto; margin-right: auto; }
.section-tint { background: color-mix(in srgb, var(--fg) 3%, var(--bg)); }
.section-more { margin-top: 48px; display: flex; flex-wrap: wrap; gap: 16px 32px; }
.section-head.center + * + .section-more, .center-more { justify-content: center; }

/* Chapter intros */
.chapter-intro { padding: clamp(72px, 9vw, 120px) 0 0; text-align: center; border-top: 1px solid var(--border); }
.chapter-intro-title { margin-top: 18px; font: 700 clamp(44px, 7vw, 96px)/1 var(--font-display); letter-spacing: -.045em; color: var(--fg); }
.chapter-intro + .section { border-top: 0; }

/* ── Stage (dark in both modes) ───────────────────────── */
.stage { background: var(--panel); color: var(--panel-fg); padding: clamp(80px, 10vw, 136px) 0; }
.stage-head { text-align: center; margin-bottom: clamp(48px, 6vw, 80px); }
.stage-head h2 { margin-top: 18px; font-size: clamp(36px, 5vw, 64px); line-height: 1.05; letter-spacing: -.035em; }
.stage-head .section-lede { margin: 24px auto 0; color: var(--panel-muted); }

/* TLS analogy */
.analogy { display: grid; grid-template-columns: 1fr 1fr; border: 1px solid var(--panel-border); margin-bottom: clamp(64px, 8vw, 104px); }
.analogy > div { padding: clamp(28px, 3.4vw, 44px); }
.analogy > div + div { border-left: 1px solid var(--accent-on-panel); background: rgba(147, 169, 224, .05); }
.analogy-kind { font: 500 11px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--panel-muted); }
.analogy > div + div .analogy-kind { color: var(--accent-on-panel); }
.analogy p:not([class]) { margin-top: 16px; font: 700 clamp(22px, 2.2vw, 30px)/1.25 var(--font-display); letter-spacing: -.02em; }
.analogy-note { margin-top: 14px; font-size: 16px; color: var(--panel-muted); }

/* Envelope anatomy explorer */
.anatomy { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 40px; align-items: start; }
.anatomy-tabs { display: flex; flex-direction: column; border-top: 1px solid var(--panel-border); }
.anatomy-tab {
  display: grid; grid-template-columns: 40px 1fr; gap: 12px; align-items: baseline;
  width: 100%; padding: 22px 16px 22px 0; text-align: left; background: none; border: 0; border-bottom: 1px solid var(--panel-border);
  color: var(--panel-muted); position: relative; transition: color .25s var(--ease), background-color .25s var(--ease);
}
.anatomy-tab::before { content: ""; position: absolute; left: 0; top: -1px; bottom: -1px; width: 2px; background: var(--accent-on-panel); transform: scaleY(0); transition: transform .3s var(--ease); }
.anatomy-tab:hover { color: var(--panel-fg); }
.anatomy-tab[aria-selected="true"] { color: var(--panel-fg); background: rgba(147, 169, 224, .05); }
.anatomy-tab[aria-selected="true"]::before { transform: none; }
.anatomy-tab .num { padding-left: 16px; font: 400 12px/1 var(--font-mono); color: var(--accent-on-panel); }
.anatomy-tab strong { display: block; font: 700 20px/1.25 var(--font-display); letter-spacing: -.015em; }
.anatomy-tab small { display: block; margin-top: 6px; font-size: 15px; line-height: 1.5; color: var(--panel-muted); }
.anatomy-tab .progress { position: absolute; left: 0; right: 0; bottom: -1px; height: 1px; background: var(--accent-on-panel); transform-origin: left; transform: scaleX(0); }
.anatomy-panel { border: 1px solid var(--panel-border); background: #111619; }
.anatomy-panel .panel-title { padding: 14px 24px; margin: 0; }
.anatomy-code { margin: 0; padding: 20px 0; overflow-x: auto; font: 400 13px/1.85 var(--font-mono); color: var(--panel-muted); }
.anatomy-code .ln { display: block; padding: 0 24px; border-left: 2px solid transparent; transition: background-color .3s var(--ease), color .3s var(--ease), border-color .3s var(--ease); white-space: pre; }
.anatomy-code .ln.is-hl { background: rgba(147, 169, 224, .1); border-left-color: var(--accent-on-panel); color: var(--panel-fg); }
.anatomy-code .k { color: var(--accent-on-panel); }
.anatomy-code .c { color: rgba(233, 238, 241, .42); }
.anatomy-note { padding: 20px 24px 24px; border-top: 1px solid var(--panel-border); min-height: 128px; }
.anatomy-note p { font-size: 16px; line-height: 1.6; color: var(--panel-muted); }
.anatomy-note p strong { color: var(--panel-fg); }
.anatomy-note .eyebrow { display: block; margin-bottom: 10px; }

/* ── Panels (dark in both modes) ──────────────────────── */
.panel { background: var(--panel); color: var(--panel-fg); padding: 32px; font: 400 14px/1.9 var(--font-mono); }
.panel-title { display: flex; justify-content: space-between; align-items: center; gap: 16px; padding-bottom: 16px; margin-bottom: 8px; border-bottom: 1px solid var(--panel-border); font: 400 12px/1.4 var(--font-mono); color: var(--panel-muted); }
.code { padding: 0; }
.code .panel-title { padding: 16px 24px; margin: 0; }
.code pre { margin: 0; padding: 24px; overflow-x: auto; font-size: 13px; line-height: 1.85; tab-size: 4; }
.code .k { color: var(--accent-on-panel); }
.code .s { color: var(--panel-fg); }
.code .c { color: var(--panel-muted); }
.code code { color: var(--panel-muted); }
.copy { background: none; border: 1px solid var(--panel-border); color: var(--panel-fg); padding: 4px 10px; font: 500 11px/1.4 var(--font-mono); letter-spacing: .06em; text-transform: uppercase; }
.copy:hover { border-color: var(--accent-on-panel); }

/* ── Intents: sequence diagram ────────────────────────── */
.intents { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: 56px; align-items: start; }
.sequence { padding: 0; }
.sequence .panel-title { padding: 16px 24px; margin: 0; }
.seq-switch { display: inline-flex; border: 1px solid var(--panel-border); }
.seq-switch button { background: none; border: 0; padding: 4px 10px; font: 500 11px/1.4 var(--font-mono); letter-spacing: .06em; text-transform: uppercase; color: var(--panel-muted); }
.seq-switch button[aria-pressed="true"] { background: var(--accent-on-panel); color: #0D1114; }
.seq-body { position: relative; padding: 24px 24px 28px; }
.seq-actors { display: grid; grid-template-columns: repeat(3, 1fr); text-align: center; font: 500 11px/1.3 var(--font-mono); letter-spacing: .14em; text-transform: uppercase; color: var(--panel-muted); }
.seq-actors span { padding: 10px 4px; border: 1px solid var(--panel-border); margin: 0 8%; }
.seq-actors span.human { border-style: dashed; }
.seq-rows { position: relative; margin-top: 8px; }
.seq-rows::before, .seq-rows::after, .seq-lane-mid { content: ""; position: absolute; top: 0; bottom: 0; width: 0; border-left: 1px dashed var(--panel-border); }
.seq-rows::before { left: calc(100% / 6); }
.seq-rows::after { left: calc(100% * 5 / 6); }
.seq-lane-mid { left: 50%; }
.seq-row { position: relative; height: 56px; }
.seq-arrow { position: absolute; top: 34px; height: 0; border-top: 1px solid var(--accent-on-panel); }
.seq-arrow::after { content: ""; position: absolute; top: -5px; border: 5px solid transparent; }
.seq-arrow.right::after { right: -1px; border-left: 7px solid var(--accent-on-panel); border-right: 0; }
.seq-arrow.left::after { left: -1px; border-right: 7px solid var(--accent-on-panel); border-left: 0; }
.seq-arrow.muted { border-top-color: var(--panel-muted); border-top-style: dashed; }
.seq-arrow.muted.right::after { border-left-color: var(--panel-muted); }
.seq-arrow.muted.left::after { border-right-color: var(--panel-muted); }
.seq-label { position: absolute; top: 8px; transform: translateX(-50%); font: 400 12px/1.4 var(--font-mono); color: var(--panel-fg); white-space: nowrap; background: var(--panel); padding: 0 6px; }
.seq-label em { font-style: normal; color: var(--accent-on-panel); }
.seq-arrow.seq-a-b { left: calc(100% / 6); right: 50%; }
.seq-arrow.seq-b-h { left: 50%; right: calc(100% / 6); }
.seq-out { margin-top: 12px; padding-top: 16px; border-top: 2px solid var(--accent-on-panel); display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; font: 400 13px/1.5 var(--font-mono); color: var(--accent-on-panel); }
.sequence.is-animated .seq-row { opacity: 0; transform: translateY(6px); transition: opacity .45s var(--ease), transform .45s var(--ease); }
.sequence.is-animated .seq-row.is-in { opacity: 1; transform: none; }
.sequence.is-animated .seq-out { opacity: 0; transition: opacity .4s var(--ease); }
.sequence.is-animated .seq-out.is-in { opacity: 1; }
.intent-list { border-top: 2px solid var(--fg); }
.intent-list li { display: grid; grid-template-columns: minmax(150px, auto) 1fr; gap: 8px 24px; padding: 18px 0; border-bottom: 1px solid var(--border); }
.intent-list code { font-size: 14px; color: var(--accent); }
.intent-list p { font-size: 16px; line-height: 1.55; color: var(--muted); }

/* ── Features grid ────────────────────────────────────── */
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 56px 48px; }
.feature { border-top: 1px solid var(--border); padding-top: 20px; }
.feature-num { font: 400 12px/1 var(--font-mono); color: var(--muted); }
.feature h3 { margin-top: 16px; font-size: 21px; letter-spacing: -.015em; }
.feature p { margin-top: 10px; font-size: 16px; color: var(--muted); }
.feature code { font-size: 14px; color: var(--fg); }

/* ── Architecture stack ───────────────────────────────── */
.arch { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 80px; align-items: center; }
.arch-copy h2 { margin-top: 18px; font-size: clamp(36px, 4.4vw, 60px); line-height: 1.05; letter-spacing: -.035em; }
.arch-copy .section-lede { margin-top: 24px; }
.arch-notes { margin-top: 40px; display: grid; gap: 0; border-top: 1px solid var(--border); }
.arch-notes div { padding: 18px 0; border-bottom: 1px solid var(--border); }
.arch-notes h3 { font-size: 19px; letter-spacing: -.015em; }
.arch-notes p { margin-top: 6px; font-size: 16px; color: var(--muted); }
.stack { padding: 28px; display: flex; flex-direction: column; gap: 10px; }
.stack .panel-title { margin-bottom: 8px; }
.stack-layer { position: relative; display: flex; justify-content: space-between; align-items: baseline; gap: 16px; flex-wrap: wrap; padding: 18px 20px; border: 1px solid var(--panel-border); transition: border-color .4s var(--ease), background-color .4s var(--ease), box-shadow .4s var(--ease); }
.stack-layer strong { font: 700 18px/1.3 var(--font-display); letter-spacing: -.015em; }
.stack-layer span { font-size: 12px; color: var(--panel-muted); text-align: right; }
.stack-layer.yours { border-style: dashed; }
.stack-arsia { border-color: var(--accent-on-panel); background: rgba(147, 169, 224, .07); }
.stack-arsia strong { color: var(--accent-on-panel); }
.stack-split { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.stack-split .stack-layer { flex-direction: column; align-items: flex-start; gap: 4px; }
.stack-split .stack-layer span { text-align: left; }
.stack-layer.is-on { border-color: var(--accent-on-panel); box-shadow: 0 0 0 1px var(--accent-on-panel), 0 0 40px rgba(147, 169, 224, .16); background: rgba(147, 169, 224, .08); }
.stack-layer.yours.is-on { border-color: var(--panel-fg); box-shadow: 0 0 0 1px rgba(233, 238, 241, .5); background: rgba(233, 238, 241, .03); }
.stack-caption { margin-top: 8px; font-size: 12px; color: var(--panel-muted); }

/* ── Compliance profiles table ────────────────────────── */
.table-wrap { overflow-x: auto; border-top: 2px solid var(--fg); }
.profiles-table, .doc table { width: 100%; border-collapse: collapse; min-width: 760px; }
.profiles-table th, .doc th { padding: 14px 16px 14px 0; text-align: left; font: 500 11px/1.3 var(--font-mono); letter-spacing: .14em; text-transform: uppercase; color: var(--muted); border-bottom: 1px solid var(--border); vertical-align: bottom; }
.profiles-table td, .doc td { padding: 18px 16px 18px 0; border-bottom: 1px solid var(--border); font-size: 16px; vertical-align: top; }
.profiles-table td:first-child { font: 500 13px/1.5 var(--font-mono); color: var(--accent); white-space: nowrap; }
.profiles-table td small { display: block; font-size: 13px; color: var(--muted); }
.profiles-table tbody tr { transition: background-color .2s var(--ease); }
.profiles-table tbody tr:hover { background: color-mix(in srgb, var(--fg) 3%, transparent); }
.req { display: inline-flex; align-items: center; gap: 8px; }
.req::before { content: ""; width: 7px; height: 7px; background: var(--accent); flex-shrink: 0; }
.opt { color: var(--muted); }
.table-note { margin-top: 20px; font-size: 14px; color: var(--muted); max-width: 820px; }
.frameworks { margin-top: 56px; }
.frameworks-label { font: 500 12px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--muted); padding-bottom: 16px; margin-bottom: 20px; border-bottom: 1px solid var(--border); }
.pills { display: flex; flex-wrap: wrap; gap: 8px; }
.pills li { padding: 8px 12px; border: 1px solid var(--border); font: 400 13px/1.4 var(--font-mono); color: var(--muted); transition: border-color .2s var(--ease), color .2s var(--ease); }
.pills li:hover { border-color: var(--fg); color: var(--fg); }
.pills li.pill-own { border-style: dashed; color: var(--accent); }

/* ── Tiles (specification documents, community) ───────── */
.tile-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.tile {
  position: relative; overflow: hidden;
  display: flex; flex-direction: column; min-height: 280px; padding: 32px;
  border: 1px solid var(--border); background: var(--bg);
  transition: border-color .25s var(--ease);
}
a.tile:hover { border-color: var(--fg); }
.tile > :not(.sr-only) { position: relative; }
.tile::before {
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: 0; transition: opacity .3s var(--ease);
  background: radial-gradient(360px circle at var(--mx, 50%) var(--my, 50%), color-mix(in srgb, var(--accent-surface) 16%, transparent), transparent 65%);
}
.tile:hover::before { opacity: 1; }
.tile-kind { font: 500 11px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--muted); }
.tile-status { font: 500 11px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--accent); }
.tile-name { margin-top: auto; padding-top: 48px; font: 700 clamp(26px, 2.4vw, 34px)/1.1 var(--font-display); letter-spacing: -.03em; }
.tile-text { margin-top: 12px; color: var(--muted); }
.tile-more { margin-top: 24px; padding-top: 0; font: 500 12px/1.4 var(--font-mono); letter-spacing: .04em; color: var(--accent); }

.stats { margin-top: 56px; display: grid; grid-template-columns: repeat(4, 1fr); border-top: 2px solid var(--fg); }
.stats div { padding: 24px 24px 0 0; }
.stats div + div { padding-left: 24px; border-left: 1px solid var(--border); }
.stats strong { display: block; font: 700 clamp(30px, 3vw, 44px)/1 var(--font-display); letter-spacing: -.03em; font-variant-numeric: tabular-nums; }
.stats span { display: block; margin-top: 10px; font: 500 11px/1.4 var(--font-mono); letter-spacing: .14em; text-transform: uppercase; color: var(--muted); }

.licenses { margin-top: 56px; }
.license-row { display: grid; grid-template-columns: 1fr auto; gap: 24px; padding: 16px 0; border-bottom: 1px solid var(--border); }
.license-row span { font: 400 14px/1.6 var(--font-mono); color: var(--accent); white-space: nowrap; }

/* ── Build ────────────────────────────────────────────── */
.build { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 80px; align-items: start; }
.build-copy h2 { margin-top: 18px; font-size: clamp(36px, 4.4vw, 60px); line-height: 1.05; letter-spacing: -.035em; }
.build-copy .section-lede { margin-top: 24px; }
.build-steps { margin-top: 40px; border-top: 2px solid var(--fg); counter-reset: step; }
.build-steps li { display: grid; grid-template-columns: 44px 1fr; gap: 12px; padding: 20px 0; border-bottom: 1px solid var(--border); }
.build-steps .step-num { font: 400 13px/1.6 var(--font-mono); color: var(--accent); }
.build-steps strong { display: block; font: 700 19px/1.3 var(--font-display); letter-spacing: -.015em; }
.build-steps p { margin-top: 4px; font-size: 16px; color: var(--muted); }
.build-steps code { font-size: 14px; color: var(--fg); }
.build-visual > .panel + .panel { margin-top: 16px; }
.build-actions { margin-top: 32px; display: flex; flex-wrap: wrap; gap: 16px 28px; align-items: center; }
.term { padding: 0; }
.term .panel-title { padding: 14px 24px; margin: 0; }
.term-lines { padding: 18px 24px 22px; min-height: 124px; font-size: 13px; line-height: 1.9; }
.term-prompt { color: var(--accent-on-panel); }
.term-ok { color: var(--accent-on-panel); }
.term-ok::before { content: "✓ "; }
.term.is-animated .term-ok { opacity: 0; transition: opacity .4s var(--ease); }
.term.is-animated .term-ok.is-in { opacity: 1; }
.caret { display: inline-block; width: 8px; height: 1.1em; margin-left: 2px; vertical-align: -3px; background: var(--panel-fg); animation: blink 1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0; } }
@keyframes pulse { 50% { opacity: .3; } }

/* ── Contact ──────────────────────────────────────────── */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 96px; align-items: start; }
.contact-copy h2 { margin-top: 18px; }
.contact-copy .section-lede { margin-top: 24px; }
.contact-direct { margin-top: 48px; border-top: 2px solid var(--fg); }
.contact-direct div { display: flex; justify-content: space-between; gap: 24px; padding: 16px 0; border-bottom: 1px solid var(--border); font: 400 14px/1.6 var(--font-mono); }
.contact-direct dt { color: var(--muted); }
.contact-direct dd { text-align: right; }
.contact-direct a:hover { color: var(--accent); }
.contact-form { padding-top: 8px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.field { margin-bottom: 22px; }
.field label { display: block; margin-bottom: 8px; font: 500 12px/1.4 var(--font-mono); letter-spacing: .04em; color: var(--muted); }
.field input, .field select, .field textarea {
  width: 100%; padding: 14px; border: 1px solid var(--muted); border-radius: 0;
  background: var(--bg); color: var(--fg); font: 400 17px/1.5 var(--font-body);
  transition: border-color .2s var(--ease);
}
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--accent-surface); outline: 2px solid var(--accent-surface); outline-offset: -1px; }
.field textarea { resize: vertical; min-height: 140px; }
.hp-field { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); }
.form-privacy { margin-bottom: 24px; font-size: 15px; color: var(--muted); }
.privacy-open { background: none; border: 0; padding: 0; color: inherit; text-decoration: underline; text-underline-offset: 3px; }
.form-submit { min-width: 200px; }
.form-error { margin-top: 20px; border-left: 2px solid var(--fg); padding: 12px 18px; font-size: 15px; }
.form-success { border-top: 2px solid var(--fg); padding-top: 24px; }
.form-success h3 { font-size: 32px; letter-spacing: -.03em; }
.form-success h3:focus { outline: none; }
.form-success p { margin-top: 12px; color: var(--muted); }

/* ── Footer ───────────────────────────────────────────── */
.footer { border-top: 1px solid var(--border); padding: 64px 0 40px; font-size: 14px; }
.footer-top { display: grid; grid-template-columns: 1fr 2fr; gap: 48px; }
.footer-logo { display: block; width: 201.13px; padding: 12px 0; color: var(--fg); line-height: 0; }
.footer-logo svg { width: 201.13px; height: 29.44px; display: block; }
.footer-tagline { margin-top: 16px; color: var(--muted); max-width: 300px; }
.footer-endorse { display: inline-block; margin-top: 16px; font: 400 13px/1.6 var(--font-mono); color: var(--muted); }
.footer-endorse:hover { color: var(--accent); }
.footer-cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.footer-cols > div { display: flex; flex-direction: column; align-items: flex-start; gap: 2px; }
.footer-head { font: 500 11px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--muted); margin-bottom: 6px; }
.footer-cols a, .footer-cols .privacy-open { color: var(--fg); text-decoration: none; padding: 5px 0; }
.footer-cols a:hover, .footer-cols .privacy-open:hover { color: var(--accent); }
.footer-bottom { margin-top: 56px; padding-top: 24px; border-top: 1px solid var(--border); display: flex; justify-content: space-between; align-items: flex-end; gap: 12px 24px; flex-wrap: wrap; font: 400 12px/1.6 var(--font-mono); color: var(--muted); }
.footer-legal { display: flex; flex-direction: column; gap: 2px; }

/* ── Privacy bar ──────────────────────────────────────── */
.gdpr-bar { position: fixed; left: 0; right: 0; bottom: 0; z-index: 60; background: var(--bg); border-top: 2px solid var(--fg); padding: 20px 0; max-height: 70vh; overflow: auto; }
.gdpr-inner { display: flex; align-items: center; gap: 40px; }
.gdpr-text { flex: 1; font-size: 13px; line-height: 1.65; max-width: 900px; }
.gdpr-text p + p { margin-top: 8px; }
.gdpr-title { font: 500 12px/1.4 var(--font-mono); letter-spacing: .04em; }
.gdpr-text a { text-decoration: underline; text-underline-offset: 3px; }
.gdpr-actions { display: flex; gap: 12px; flex-shrink: 0; }
body.gdpr-visible { padding-bottom: var(--privacy-height, 200px); }

/* ── Documentation pages ──────────────────────────────── */
.page-head { padding: clamp(64px, 8vw, 112px) 0 clamp(40px, 5vw, 64px); border-bottom: 1px solid var(--border); }
.page-head h1 { margin-top: 18px; font-size: clamp(40px, 5.4vw, 72px); line-height: 1.04; letter-spacing: -.035em; max-width: 960px; }
.page-head .section-lede { margin-top: 24px; }
.page-meta { margin-top: 28px; display: flex; flex-wrap: wrap; gap: 8px; }
.page-meta span { padding: 6px 10px; border: 1px solid var(--border); font: 400 12px/1.4 var(--font-mono); color: var(--muted); }
.docs { display: grid; grid-template-columns: 220px minmax(0, 1fr) 200px; gap: 56px; padding-top: 56px; padding-bottom: clamp(88px, 10vw, 136px); align-items: start; }
.docs-side, .docs-toc { position: sticky; top: calc(var(--nav-h) + 32px); max-height: calc(100vh - var(--nav-h) - 64px); overflow: auto; }
.docs-side .group + .group { margin-top: 28px; }
.docs-side .group-title, .docs-toc .group-title { display: block; margin-bottom: 10px; font: 500 11px/1.3 var(--font-mono); letter-spacing: .16em; text-transform: uppercase; color: var(--muted); }
.docs-side a { display: block; padding: 6px 0 6px 14px; border-left: 1px solid var(--border); font-size: 15px; color: var(--muted); transition: color .2s var(--ease), border-color .2s var(--ease); }
.docs-side a:hover { color: var(--fg); }
.docs-side a[aria-current="page"] { color: var(--fg); border-left: 2px solid var(--accent); padding-left: 13px; }
.docs-status { margin-top: 32px; padding-top: 18px; border-top: 1px solid var(--border); font: 400 12px/1.7 var(--font-mono); color: var(--muted); }
.docs-status .status-dot { display: inline-block; margin-right: 8px; vertical-align: 1px; background: var(--accent); }
.docs-toc a { display: block; padding: 5px 0; font-size: 14px; color: var(--muted); transition: color .2s var(--ease); }
.docs-toc a:hover, .docs-toc a.is-active { color: var(--fg); }
.doc { max-width: 760px; }
.doc > section + section { margin-top: 64px; padding-top: 48px; border-top: 1px solid var(--border); }
.doc > .callout + section { margin-top: 48px; }
.doc > section > * + * { margin-top: 18px; }
.doc h2 { font-size: clamp(28px, 2.8vw, 36px); letter-spacing: -.03em; }
.doc h3 { margin-top: 36px; font-size: 21px; letter-spacing: -.015em; }
.doc h2 + p, .doc h2 + .table-wrap, .doc h3 + p { margin-top: 18px; }
.doc p + p, .doc p + ul, .doc ul + p, .doc p + ol, .doc .code + p, .doc p + .code, .doc .callout + p, .doc p + .callout, .doc .table-wrap + p, .doc p + .table-wrap, .doc ol + p { margin-top: 18px; }
.doc p, .doc li { color: var(--muted); }
.doc p strong, .doc li strong { color: var(--fg); }
.doc a:not(.btn):not(.link-card) { color: var(--accent); border-bottom: 1px solid color-mix(in srgb, var(--accent) 35%, transparent); }
.doc a:not(.btn):not(.link-card):hover { border-bottom-color: currentColor; }
.doc :not(pre) > code { font-size: .88em; padding: 1px 6px; background: color-mix(in srgb, var(--fg) 6%, transparent); color: var(--fg); }
.doc ul.bullets li, .doc ol.numbered li { position: relative; padding-left: 28px; }
.doc ul.bullets li + li, .doc ol.numbered li + li { margin-top: 10px; }
.doc ul.bullets li::before { content: ""; position: absolute; left: 4px; top: .7em; width: 6px; height: 6px; background: var(--accent); }
.doc ol.numbered { counter-reset: n; }
.doc ol.numbered li { counter-increment: n; }
.doc ol.numbered li::before { content: counter(n, decimal-leading-zero); position: absolute; left: 0; top: .15em; font: 400 12px/1.6 var(--font-mono); color: var(--accent); }
.doc .code { margin-top: 24px; }
.doc .code + .code { margin-top: 16px; }
.doc .table-wrap { margin-top: 24px; }
.doc table { min-width: 560px; }
.doc td { color: var(--muted); font-size: 15px; }
.doc td:first-child { color: var(--fg); }
.callout { margin-top: 28px; padding: 22px 24px; border-left: 2px solid var(--accent); background: color-mix(in srgb, var(--accent) 6%, var(--bg)); }
.callout strong { display: block; font: 700 17px/1.4 var(--font-display); color: var(--fg); }
.callout p { margin-top: 6px; font-size: 16px; }
.result { margin-top: 16px; padding: 16px 24px; border: 1px solid var(--border); font: 400 13px/1.7 var(--font-mono); }
.result .eyebrow { display: block; margin-bottom: 6px; }
.link-grid { margin-top: 24px; display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.link-card { display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 18px 20px; border: 1px solid var(--border); color: var(--fg); transition: border-color .2s var(--ease); }
.link-card:hover { border-color: var(--fg); }
.link-card span:last-child { color: var(--accent); }
.level-grid { margin-top: 24px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.level-grid > div { padding: 22px; border: 1px solid var(--border); }
.level-grid > div:last-child { border-color: var(--accent); }
.level-grid h3 { margin-top: 14px; font-size: 21px; }
.level-grid p { margin-top: 8px; font-size: 15px; }
.mini-flow { margin-top: 24px; display: flex; flex-wrap: wrap; align-items: center; gap: 8px; font: 400 13px/1.4 var(--font-mono); color: var(--muted); }
.mini-flow span { padding: 8px 12px; border: 1px solid var(--border); }
.mini-flow i { font-style: normal; color: var(--accent); }
.mini-flow strong { padding: 8px 12px; border: 1px solid var(--accent); color: var(--accent); font-weight: 500; }
.doc details { border-top: 1px solid var(--border); }
.doc details:last-of-type { border-bottom: 1px solid var(--border); }
.doc summary { display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 18px 0; cursor: pointer; list-style: none; font: 700 18px/1.35 var(--font-display); letter-spacing: -.01em; color: var(--fg); }
.doc summary::-webkit-details-marker { display: none; }
.doc summary::after { content: "+"; font: 400 20px/1 var(--font-mono); color: var(--accent); transition: transform .2s var(--ease); }
.doc details[open] summary::after { transform: rotate(45deg); }
.doc details > :not(summary) { padding-bottom: 20px; }
.doc details .profile-meta { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 24px; margin: 4px 0 16px; }
.doc details .profile-meta div { display: flex; justify-content: space-between; gap: 12px; padding: 10px 0; border-bottom: 1px solid var(--border); font: 400 13px/1.5 var(--font-mono); }
.doc details .profile-meta dt { color: var(--muted); }
.doc details .profile-meta dd { color: var(--fg); text-align: right; }
.summary-meta { display: block; margin-top: 4px; font: 400 12px/1.4 var(--font-mono); color: var(--muted); letter-spacing: 0; }
.filter { margin-top: 24px; display: flex; align-items: center; gap: 12px; }
.filter input { flex: 1; padding: 12px 14px; border: 1px solid var(--muted); background: var(--bg); color: var(--fg); font: 400 16px/1.5 var(--font-body); border-radius: 0; }
.filter input:focus { outline: 2px solid var(--accent-surface); outline-offset: -1px; border-color: var(--accent-surface); }
.filter-count { font: 400 12px/1.4 var(--font-mono); color: var(--muted); white-space: nowrap; }
#profileList { margin-top: 20px; }

.not-found { padding: clamp(96px, 14vw, 180px) 0; }
.not-found h1 { margin-top: 18px; font-size: clamp(44px, 6vw, 84px); letter-spacing: -.04em; }
.not-found p:not(.eyebrow) { margin-top: 20px; color: var(--muted); font-size: 19px; }
.not-found .btn { margin-top: 36px; }

/* ── Search ───────────────────────────────────────────── */
.search-dialog { width: min(640px, calc(100% - 32px)); max-height: min(560px, calc(100vh - 96px)); margin: 12vh auto 0; padding: 0; border: 1px solid var(--fg); border-radius: 0; background: var(--bg); color: var(--fg); }
.search-dialog::backdrop { background: rgba(13, 17, 20, .55); -webkit-backdrop-filter: blur(4px); backdrop-filter: blur(4px); }
.search-head { display: flex; align-items: center; gap: 12px; padding: 12px 12px 12px 20px; border-bottom: 1px solid var(--border); }
.search-head input { flex: 1; min-width: 0; padding: 10px 0; border: 0; background: none; color: var(--fg); font: 400 18px/1.4 var(--font-body); outline: none; }
.search-head kbd { padding: 2px 6px; border: 1px solid var(--border); font-size: 11px; color: var(--muted); }
.search-results { max-height: 420px; overflow: auto; padding: 8px 0; }
.search-results a { display: block; padding: 12px 20px; border-left: 2px solid transparent; }
.search-results a:hover, .search-results a[aria-selected="true"] { background: color-mix(in srgb, var(--fg) 4%, transparent); border-left-color: var(--accent); }
.search-results strong { display: block; font: 700 16px/1.35 var(--font-display); }
.search-results span { display: block; margin-top: 2px; font-size: 14px; color: var(--muted); }
.search-empty { padding: 20px; color: var(--muted); font-size: 15px; }
.search-kbd { display: inline-flex; align-items: center; gap: 8px; }
.search-kbd kbd { font-size: 10px; padding: 1px 5px; border: 1px solid currentColor; opacity: .6; }

/* ── Headlines reveal line by line ────────────────────── */
.split .line { display: block; overflow: hidden; padding-bottom: .1em; margin-bottom: -.1em; }
.split .line-inner { display: block; }
@media (prefers-reduced-motion: no-preference) {
  .js .split:not(.split-ready) { opacity: 0; animation: split-fallback 0s 1.2s forwards; }
  .js .split-ready .line-inner { transform: translateY(105%); transition: transform 1s var(--ease); }
  .js .split-ready.in .line-inner { transform: none; }
  .js .split-ready .line:nth-child(2) .line-inner { transition-delay: .12s; }
  .js .split-ready .line:nth-child(3) .line-inner { transition-delay: .24s; }
}
@keyframes split-fallback { to { opacity: 1; } }

/* Chapter intros grow into place as they scroll in */
@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    .chapter-intro-title { animation: intro-grow linear both; animation-timeline: view(); animation-range: entry 0% cover 40%; }
    @keyframes intro-grow { from { opacity: .1; transform: scale(.86); } to { opacity: 1; transform: none; } }
  }
}

/* Scroll reveal (only when JS runs, and never with reduced motion) */
@media (prefers-reduced-motion: no-preference) {
  .js .reveal { opacity: 0; transform: translateY(28px); transition: opacity .9s var(--ease), transform .9s var(--ease); }
  .js .reveal.in { opacity: 1; transform: none; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .status-dot { animation: none; }
}

/* ── Responsive ───────────────────────────────────────── */
@media (max-width: 1180px) {
  .docs { grid-template-columns: 200px minmax(0, 1fr); }
  .docs-toc { display: none; }
}
@media (max-width: 1080px) {
  .nav-links { gap: 18px; }
  .anatomy, .intents, .arch, .build { grid-template-columns: minmax(0, 1fr); gap: 48px; }
}
@media (max-width: 960px) {
  :root { --gutter: 28px; }
  .nav-links, .nav-cta { display: none; }
  .nav-tools { margin-left: auto; }
  .nav-menu { display: block; margin-left: 4px; }
  .mobile-nav { border-top: 1px solid var(--border); }
  .mobile-nav:not([hidden]) { display: block; }
  .mobile-nav a { display: block; padding: 14px 0; border-bottom: 1px solid var(--border); font-size: 17px; }
  .mobile-nav a:last-child { border-bottom: 0; }
  .features, .tile-grid { grid-template-columns: 1fr 1fr; gap: 20px; }
  .features { gap: 36px 28px; }
  .contact-grid { grid-template-columns: minmax(0, 1fr); gap: 48px; }
  .analogy { grid-template-columns: 1fr; }
  .analogy > div + div { border-left: 0; border-top: 1px solid var(--accent-on-panel); }
  .metrics ul, .stats { grid-template-columns: 1fr 1fr; }
  .metrics li:nth-child(3) { border-left: 0; }
  .metrics li:nth-child(n + 3) { border-top: 1px solid var(--panel-border); }
  .stats div:nth-child(3) { padding-left: 0; border-left: 0; }
  .stats div:nth-child(n + 3) { margin-top: 24px; }
  .footer-top { grid-template-columns: 1fr; }
  .docs { grid-template-columns: minmax(0, 1fr); gap: 32px; padding-top: 32px; }
  .docs-side { position: static; max-height: none; display: flex; flex-wrap: wrap; gap: 8px; }
  .docs-side .group { display: contents; }
  .docs-side .group-title, .docs-status { display: none; }
  .docs-side a { padding: 8px 12px; border: 1px solid var(--border); font-size: 14px; }
  .docs-side a[aria-current="page"] { border: 1px solid var(--accent); padding: 8px 12px; }
  .level-grid { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
  :root { --gutter: 20px; }
  .nav-logo svg { width: 160.91px; height: 23.55px; }
  .search-kbd kbd { display: none; }
  .features, .tile-grid, .form-row, .link-grid { grid-template-columns: 1fr; }
  .form-row { gap: 0; }
  .tile { min-height: 0; }
  .tile-name { padding-top: 32px; }
  .panel { padding: 24px 20px; }
  .code pre { padding: 20px; font-size: 12px; }
  .anatomy-code { font-size: 12px; }
  .anatomy-code .ln { padding: 0 16px; }
  .hero-actions .btn { flex: 1 1 100%; }
  .install { max-width: 100%; font-size: 13px; }
  .intent-list li { grid-template-columns: 1fr; }
  .seq-label { font-size: 10px; left: 50% !important; }
  .stack-split { grid-template-columns: 1fr; }
  .footer-cols { grid-template-columns: 1fr 1fr; }
  .footer-bottom { flex-direction: column; align-items: flex-start; gap: 8px; }
  .gdpr-inner { flex-direction: column; align-items: stretch; gap: 16px; }
  .gdpr-actions .btn { flex: 1; }
  .doc details .profile-meta { grid-template-columns: 1fr; }
}

@media print {
  .nav, .gdpr-bar, .contact-form, .icon-btn, .docs-side, .docs-toc, .hero-visual { display: none !important; }
  .js .reveal { opacity: 1 !important; transform: none !important; }
  .hero, .stage, .panel, .metrics { background: #fff; color: #000; }
}