/* ============================================================
 * xlang editorial system — shared visual layer
 * Loaded after style.css and extlibs.css.
 * ============================================================ */

:root {
  color-scheme: dark;
  --bg: #09090a;
  --bg-soft: #111113;
  --bg-card: #121214;
  --bg-code: #0d0d0f;
  --bg-input: #0f0f11;
  --border: #29292d;
  --line-strong: #3a3a3f;
  --text: #f1f0ed;
  --text-soft: #aaa9ad;
  --text-muted: #727176;
  --brand: #ea6a5f;
  --brand-hover: #f27e73;
  --brand-dark: #bc5149;
  --on-brand: #120a09;
  --brand-glow: rgba(234, 106, 95, .12);
  --accent: #d89e98;
  --accent-glow: rgba(216, 158, 152, .09);
  --green: #69c69d;
  --green-glow: rgba(105, 198, 157, .09);
  --blue: #77a9d6;
  --blue-glow: rgba(119, 169, 214, .09);
  --orange: #d79762;
  --orange-glow: rgba(215, 151, 98, .09);
  --radius: 9px;
  --radius-lg: 14px;
  --shadow: 0 24px 70px rgba(0, 0, 0, .32);
  --nav-bg: rgba(9, 9, 10, .88);
  --code-kw: #ea887f;
  --code-fn: #8db9df;
  --code-str: #84c6a6;
  --code-cm: #68676c;
  --code-num: #dca276;
  --code-type: #d8bd82;
  --code-time: #d8bd82;
  --font-sans: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Noto Sans CJK SC", "Microsoft YaHei", sans-serif;
  --font-mono: "SFMono-Regular", "Cascadia Code", "JetBrains Mono", Consolas, monospace;
  --max-w: 1160px;
  --nav-h: 68px;
}

[data-theme="light"] {
  color-scheme: light;
  --bg: #f5f3ef;
  --bg-soft: #ece9e3;
  --bg-card: #fbfaf7;
  --bg-code: #efede7;
  --bg-input: #fbfaf7;
  --border: #d8d3cb;
  --line-strong: #bcb5aa;
  --text: #1c1b19;
  --text-soft: #5e5a55;
  --text-muted: #827c74;
  --brand: #c84e45;
  --brand-hover: #a83f38;
  --brand-dark: #92362f;
  --on-brand: #fffaf5;
  --brand-glow: rgba(200, 78, 69, .10);
  --accent: #9b5d58;
  --accent-glow: rgba(155, 93, 88, .08);
  --green: #287c5a;
  --green-glow: rgba(40, 124, 90, .08);
  --blue: #356f9f;
  --blue-glow: rgba(53, 111, 159, .08);
  --orange: #a86028;
  --orange-glow: rgba(168, 96, 40, .08);
  --shadow: 0 18px 55px rgba(54, 45, 35, .10);
  --nav-bg: rgba(245, 243, 239, .90);
  --code-kw: #b44740;
  --code-fn: #286b95;
  --code-str: #287756;
  --code-cm: #8d867d;
  --code-num: #9b5d2c;
  --code-type: #7d6529;
  --code-time: #7d6529;
}

* { scrollbar-color: var(--line-strong) transparent; }
html { background: var(--bg); scroll-padding-top: calc(var(--nav-h) + 24px); }
body {
  min-width: 320px;
  background:
    radial-gradient(900px 500px at 85% -80px, var(--brand-glow), transparent 62%),
    var(--bg);
  color: var(--text);
  font-size: 15px;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
}
body.nav-locked { overflow: hidden; }
a { text-underline-offset: .18em; }
::selection { color: var(--text); background: color-mix(in srgb, var(--brand) 30%, transparent); }

.skip-link {
  position: fixed; left: 18px; top: 12px; z-index: 1000;
  padding: 9px 14px; border-radius: 7px; background: var(--text); color: var(--bg);
  font-weight: 650; transform: translateY(-160%); transition: transform .15s ease;
}
.skip-link:focus { transform: none; }

/* Navigation */
.nav {
  height: var(--nav-h);
  background: var(--nav-bg);
  border-bottom: 1px solid color-mix(in srgb, var(--border) 82%, transparent);
  backdrop-filter: blur(18px) saturate(130%);
}
.nav-inner {
  max-width: 1280px; padding: 0 34px; gap: 18px;
  justify-content: flex-start;
}
.nav-logo, .brand-wordmark {
  display: inline-flex; align-items: baseline; gap: 0;
  color: var(--text); font-size: 22px; font-weight: 720; line-height: 1;
  letter-spacing: -.055em; white-space: nowrap;
}
.nav-logo:hover, .brand-wordmark:hover { color: var(--text); }
.nav-logo .logo-x, .brand-wordmark .logo-x { color: var(--brand); }
.nav-logo .logo-rest, .brand-wordmark .logo-rest { color: var(--text); }
.nav-links {
  margin-left: auto; gap: 4px; align-items: center;
}
.nav-links a {
  display: block; padding: 8px 9px; border-radius: 6px;
  color: var(--text-muted); font-size: 13px; font-weight: 560;
}
.nav-links a:hover { color: var(--text); background: var(--bg-soft); }
.nav-links a[aria-current="page"] { color: var(--text); background: var(--bg-soft); }
.nav-links a[aria-current="page"]::after {
  content: ""; display: block; width: 12px; height: 1px; margin: 4px auto -5px; background: var(--brand);
}
.nav-actions { display: flex; gap: 7px; align-items: center; }
.nav-toggle, .theme-toggle, .search-toggle {
  width: 36px; height: 36px; border-radius: 8px; border-color: var(--border);
  color: var(--text-muted); background: transparent;
}
.nav-toggle:hover, .theme-toggle:hover, .search-toggle:hover {
  border-color: var(--line-strong); color: var(--text); background: var(--bg-soft);
}
.theme-glyph { position: relative; display: block; width: 15px; height: 15px; border: 1.5px solid currentColor; border-radius: 50%; overflow: hidden; }
.theme-glyph::after { content: ""; position: absolute; inset: -2px -2px -2px 50%; background: currentColor; opacity: .48; }
[data-theme="light"] .theme-glyph::after { inset: -2px 50% -2px -2px; opacity: .22; }
.search-glyph { position: relative; display: block; width: 15px; height: 15px; border: 1.5px solid currentColor; border-radius: 50%; }
.search-glyph::after { content: ""; position: absolute; width: 6px; height: 1.5px; right: -5px; bottom: -2px; border-radius: 2px; background: currentColor; transform: rotate(45deg); transform-origin: left center; }
.nav-toggle { display: none; flex-direction: column; gap: 4px; }
.nav-toggle span { width: 16px; height: 1.5px; }

/* Shared editorial header and content */
.page-header {
  padding: calc(var(--nav-h) + 72px) 24px 64px;
  background: none; text-align: left;
  max-width: var(--max-w); margin: 0 auto; border-bottom: 1px solid var(--border);
}
.page-header::before {
  content: attr(data-label); display: block; min-height: 1em; margin-bottom: 16px;
  color: var(--brand); font: 650 11px/1.2 var(--font-mono); letter-spacing: .12em; text-transform: uppercase;
}
.page-header h1 {
  max-width: 920px; margin: 0 0 16px; color: var(--text);
  font-size: clamp(38px, 5vw, 62px); font-weight: 630; line-height: 1.12; letter-spacing: -.055em;
}
.page-header p { max-width: 760px; color: var(--text-soft); font-size: 16px; line-height: 1.85; }
.page-content { max-width: 900px; padding: 54px 24px 100px; }
.page-content h2 {
  margin: 56px 0 18px; padding-top: 34px; border-top-color: var(--border);
  color: var(--text); font-size: 25px; font-weight: 630; letter-spacing: -.025em;
}
.page-content h3 { margin-top: 34px; color: var(--text); font-size: 18px; }
.page-content p, .page-content li { color: var(--text-soft); }
.page-content strong { color: var(--text); font-weight: 650; }
.breadcrumb { margin-bottom: 30px; }
.api-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.api-card {
  padding: 22px; border-radius: 10px; background: var(--bg-card); border-color: var(--border);
  box-shadow: none; transform: none;
}
.api-card:hover { border-color: var(--line-strong); transform: none; }
.api-card h4 { color: var(--text); }

/* Home / brand-first opening */
.hero-raycast {
  position: relative; min-height: min(900px, 100vh); padding: calc(var(--nav-h) + 82px) 5vw 86px;
  display: grid; grid-template-columns: minmax(430px, .9fr) minmax(500px, 1.1fr);
  gap: clamp(44px, 7vw, 112px); align-items: center; overflow: hidden; text-align: left; background: none;
}
.hero-grid {
  position: absolute; inset: var(--nav-h) 0 0; pointer-events: none; opacity: .18;
  background-image: linear-gradient(var(--border) 1px, transparent 1px), linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 90px 90px; mask-image: linear-gradient(to bottom, #000 0, transparent 82%);
}
.hero-aurora { display: none; }
.hero-copy { position: relative; z-index: 1; display: flex; flex-direction: column; align-items: flex-start; max-width: 660px; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 12px; margin: 0 0 34px; padding: 0;
  color: var(--text-muted); border: 0; background: none; border-radius: 0;
  font: 560 10px/1 var(--font-mono); letter-spacing: .12em; text-transform: uppercase;
}
.hero-badge:hover { color: var(--text-soft); }
.hero-badge .dot { width: 18px; height: 1px; border-radius: 0; background: var(--brand); box-shadow: none; }
.hero h1.brand-display {
  margin: 0 0 24px; color: var(--text); font-family: var(--font-sans);
  font-size: clamp(96px, 11vw, 164px); font-weight: 720; line-height: .78; letter-spacing: -.095em;
}
.hero h1.brand-display .brand-x { display: inline; color: var(--brand); -webkit-text-fill-color: currentColor; }
.hero-tagline {
  max-width: 620px; margin: 0 0 16px; color: var(--text);
  font-size: clamp(26px, 2.7vw, 39px); font-weight: 530; line-height: 1.32; letter-spacing: -.05em;
}
.hero-desc { max-width: 590px; margin: 0 0 34px; color: var(--text-soft); font-size: 15px; line-height: 1.85; }
.hero-actions { justify-content: flex-start; gap: 24px; }
.hero-actions .btn {
  min-height: 34px; padding: 0 0 6px; border: 0; border-bottom: 1px solid var(--border); border-radius: 0;
  color: var(--text-soft); background: none; font-size: 13px; box-shadow: none;
}
.hero-actions .btn:hover { color: var(--text); border-bottom-color: var(--line-strong); background: none; transform: none; box-shadow: none; }
.hero-actions .btn-primary { color: var(--text); border-bottom-color: var(--brand); }
.hero-actions .btn-primary span { color: var(--brand); }
.hero-metrics { width: 100%; margin-top: 54px; padding-top: 18px; display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--border); }
.hero-metrics div { min-width: 0; }
.hero-metrics strong { display: block; color: var(--text); font: 600 11px/1.2 var(--font-mono); letter-spacing: .02em; }
.hero-metrics span { display: block; margin-top: 7px; color: var(--text-muted); font-size: 11px; }
.command-stage { position: relative; z-index: 1; width: 100%; min-width: 0; }
.command-glow { position: absolute; inset: 10% 7%; background: var(--brand); opacity: .10; filter: blur(100px); }
.command-window {
  position: relative; width: 100%; overflow: hidden; border: 1px solid var(--border); border-radius: 14px;
  background: color-mix(in srgb, var(--bg-card) 94%, transparent); box-shadow: var(--shadow);
}
.command-topbar { height: 52px; padding: 0 18px; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; border-bottom: 1px solid var(--border); color: var(--text-muted); font: 11px/1 var(--font-mono); letter-spacing: .03em; }
.command-topbar kbd { justify-self: end; }
.window-dots { display: flex; gap: 7px; }
.window-dots i { width: 7px; height: 7px; border-radius: 50%; background: var(--line-strong); }
.command-search { height: 84px; padding: 0 26px; display: flex; align-items: center; gap: 14px; border-bottom: 1px solid var(--border); color: var(--text); font: 18px/1 var(--font-mono); }
.prompt { color: var(--brand); }
.cursor { width: 1.5px; height: 24px; background: var(--brand); animation: cursorBlink 1.15s steps(1) infinite; }
@keyframes cursorBlink { 50% { opacity: 0; } }
.command-results { padding: 10px; }
.command-item { min-height: 72px; padding: 10px 13px; display: grid; grid-template-columns: 44px 1fr auto; gap: 14px; align-items: center; border: 1px solid transparent; border-radius: 9px; color: var(--text-soft); }
.command-item.active { border-color: var(--border); background: var(--bg-soft); }
.command-item b { display: block; color: var(--text); font-size: 14px; font-weight: 610; }
.command-item small { display: block; margin-top: 3px; color: var(--text-muted); font: 11px/1.35 var(--font-mono); }
.command-item kbd, .command-topbar kbd { color: var(--text-muted); font: 10px/1 var(--font-mono); border: 1px solid var(--border); border-radius: 5px; padding: 5px 7px; }
.command-icon { width: 42px; height: 30px; display: grid; place-items: center; color: var(--text-muted); border: 1px solid var(--line-strong); border-radius: 6px; background: var(--bg-card); font: 600 9px/1 var(--font-mono); letter-spacing: .05em; }
.terminal-strip { height: 58px; padding: 0 20px; display: flex; align-items: center; gap: 12px; border-top: 1px solid var(--border); color: var(--text-soft); }
.terminal-ok { color: var(--green); font-size: 9px; }
.terminal-meta { margin-left: auto; color: var(--text-muted); font: 10px/1 var(--font-mono); }
.floating-chip { display: none; }

/* Home sections */
.section, .platform-section { max-width: var(--max-w); padding: 96px 24px; }
.section + .section, .section + .platform-section, .platform-section + .section { border-top: 1px solid color-mix(in srgb, var(--border) 62%, transparent); }
.section-kicker { margin-bottom: 18px; color: var(--brand); font: 650 11px/1 var(--font-mono); letter-spacing: .12em; }
.section-title { max-width: 760px; margin-bottom: 14px; color: var(--text); font-size: clamp(31px, 4vw, 46px); font-weight: 620; letter-spacing: -.045em; }
.section-desc { max-width: 690px; margin-bottom: 42px; color: var(--text-soft); font-size: 15px; line-height: 1.8; }
.hl-grid-editorial { grid-template-columns: repeat(3, 1fr); gap: 0; border-top: 1px solid var(--border); border-left: 1px solid var(--border); }
.hl-card {
  min-height: 200px; padding: 26px; border-radius: 0; border: 0; border-right: 1px solid var(--border); border-bottom: 1px solid var(--border);
  background: transparent; box-shadow: none;
}
.hl-card::before { display: none; }
.hl-card:hover { border-color: var(--border); background: var(--bg-card); transform: none; box-shadow: none; }
.hl-icon { margin-bottom: 34px; color: var(--brand); font: 600 10px/1 var(--font-mono); letter-spacing: .08em; }
.hl-card h4 { margin-bottom: 9px; font-size: 17px; font-weight: 620; }
.hl-card p { color: var(--text-muted); font-size: 13px; line-height: 1.75; }
.platform-matrix { gap: 18px; margin-top: 34px; }
.platform-group { padding: 24px; border: 1px solid var(--border); border-radius: 10px; background: var(--bg-card); }
.platform-group h4 { margin-bottom: 15px; font: 600 10px/1 var(--font-mono); letter-spacing: .11em; }
.platform-badges { gap: 8px; }
.platform-badge { padding: 7px 11px; border-radius: 6px; background: transparent; border-color: var(--border); color: var(--text-soft); font-size: 12px; }
.platform-badge:hover { border-color: var(--line-strong); color: var(--text); transform: none; }
.platform-advantage { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; margin-top: 14px; }
.platform-advantage .hl-card { min-height: 180px; border: 1px solid var(--border); border-radius: 10px; }
.feature-grid { grid-template-columns: repeat(3, 1fr); gap: 10px; }
.feature-card { padding: 24px; border-radius: 10px; background: var(--bg-card); border-color: var(--border); box-shadow: none; }
.feature-card:hover { border-color: var(--line-strong); box-shadow: none; transform: none; }
.feature-icon { width: auto; height: auto; margin-bottom: 27px; justify-content: flex-start; border-radius: 0; color: var(--brand) !important; background: none !important; font: 600 10px/1 var(--font-mono); }
.feature-card h3 { font-size: 16px; font-weight: 620; }
.feature-card p { color: var(--text-muted); font-size: 13px; }
.feature-tag { border-radius: 5px; background: transparent; border-color: var(--border); font-size: 10px; }
.std-grid { grid-template-columns: repeat(3, 1fr); gap: 8px; }
.std-card { min-height: 104px; padding: 17px; border-radius: 8px; background: var(--bg-card); }
.std-card h4 { color: var(--text); }
.stat-card { border-radius: 8px; background: var(--bg-card); }

/* Code and tables */
.code-block { border-radius: 10px; border-color: var(--border); background: var(--bg-code); box-shadow: none; }
.code-header { min-height: 43px; padding: 10px 15px; border-color: var(--border); background: var(--bg-soft); }
.code-header > span:first-child { font-size: 11px; }
.code-body { padding: 18px 20px; }
.code-body pre { font-size: 13px; line-height: 1.72; tab-size: 4; }
.copy-btn { border-radius: 5px; border-color: var(--border); }
.copy-btn:hover { border-color: var(--line-strong); color: var(--text); }
.term-block { margin: 18px 0; overflow-x: auto; border: 1px solid var(--border); border-radius: 9px; background: var(--bg-code); color: var(--text-soft); }
.t-cmd, .c-cmd { color: var(--blue); }
.t-cm, .c-cm { color: var(--text-muted); }
.t-err, .c-err { color: var(--brand); }
.c-out { color: var(--green); }
.book-summary-table, .ext-kv, .api-table { border-collapse: separate; border-spacing: 0; overflow: hidden; border: 1px solid var(--border); border-radius: 9px; }
.book-summary-table th, .book-summary-table td, .api-table th, .api-table td { border: 0; border-bottom: 1px solid var(--border); padding: 10px 13px; }
.book-summary-table tr:last-child td, .api-table tr:last-child td { border-bottom: 0; }

/* Tour and chapters */
.tour-layout { max-width: var(--max-w); grid-template-columns: 220px minmax(0, 1fr); gap: 54px; padding: 48px 24px 104px; }
.tour-sidebar { top: calc(var(--nav-h) + 20px); max-height: calc(100vh - var(--nav-h) - 40px); padding-right: 12px; }
.tour-sidebar h4 { margin: 22px 0 8px; padding-left: 10px; color: var(--text-muted); font: 650 10px/1.2 var(--font-mono); }
.tour-sidebar li a { padding: 6px 10px; border-radius: 5px; border-left: 0; color: var(--text-muted); font-size: 12px; }
.tour-sidebar li a:hover { color: var(--text); background: var(--bg-soft); }
.tour-sidebar li a.active, .tour-sidebar li a[aria-current="true"] { color: var(--text); background: var(--bg-soft); box-shadow: inset 2px 0 var(--brand); }
.tour-content { max-width: 820px; }
.tour-section { margin-bottom: 64px; }
.tour-section h2, .tour-section h3 { color: var(--text); font-weight: 620; letter-spacing: -.02em; }
.tour-section h3 { font-size: 23px; }
.tour-section .lead { color: var(--text-soft); font-size: 14px; line-height: 1.8; }
.tour-level-badge { padding: 3px 0; border-radius: 0; color: var(--brand) !important; background: none !important; font: 650 10px/1.2 var(--font-mono); letter-spacing: .08em; }
.tour-note, .book-note, .book-deep, .book-detail, .deep-box {
  padding: 16px 18px; border: 1px solid var(--border); border-left: 2px solid var(--blue); border-radius: 8px; background: var(--bg-soft); color: var(--text-soft);
}
.book-pit, .pit-box { padding: 16px 18px; border: 1px solid var(--border); border-left: 2px solid var(--brand); border-radius: 8px; background: var(--bg-soft); }
.book-ex, .book-exercise, .exercise-box { padding: 16px 18px; border: 1px solid var(--border); border-left: 2px solid var(--green); border-radius: 8px; background: var(--bg-soft); }
.book-quiz, .quiz-list { padding: 18px 20px 18px 38px; border: 1px solid var(--border); border-radius: 8px; background: var(--bg-card); }
.box-tag { display: inline-block; margin-bottom: 8px; color: var(--text); font: 650 10px/1.2 var(--font-mono); letter-spacing: .08em; text-transform: uppercase; }
.pit-cause { margin-top: 10px; color: var(--text-muted); font-size: 13px; }
.tour-nav, .ch-prevnext, .chapter-nav { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; margin-top: 46px; padding-top: 28px; border-top: 1px solid var(--border); }
.tour-nav-link, .ch-prevnext a, .chapter-nav a { min-width: 0; padding: 16px; border: 1px solid var(--border); border-radius: 8px; background: var(--bg-card); }
.tour-nav-link:hover, .ch-prevnext a:hover, .chapter-nav a:hover { border-color: var(--line-strong); transform: none; }
.pn-dir { display: block; color: var(--text-muted); font-size: 11px; }
.pn-title { display: block; margin-top: 4px; overflow: hidden; color: var(--text); font-weight: 600; text-overflow: ellipsis; white-space: nowrap; }
.ch-disabled { opacity: .38; }

/* Book cover */
.book-hero { padding-bottom: 56px; }
.book-hero .book-kicker { color: var(--brand); font: 650 11px/1.2 var(--font-mono); letter-spacing: .12em; }
.book-hero-meta { justify-content: flex-start; }
.book-pill { border-radius: 5px; background: var(--bg-card); }
.book-path { grid-template-columns: repeat(3, 1fr); gap: 10px; }
.book-path-item, .book-vol { border-radius: 9px; background: var(--bg-card); border-color: var(--border); }
.book-path-tag { color: var(--brand); font-family: var(--font-mono); }
.book-toc { gap: 12px; }
.book-vol-head { border-bottom-color: var(--border); }
.book-ch a { border-radius: 5px; }
.book-ch a:hover { background: var(--bg-soft); }
.badge { border-radius: 4px; }

/* Standard library */
.stdlib-layout { max-width: var(--max-w); padding: 34px 24px 100px; }
.stdlib-search { position: sticky; top: calc(var(--nav-h) + 12px); z-index: 20; margin-bottom: 12px; padding: 10px; border: 1px solid var(--border); border-radius: 10px; background: color-mix(in srgb, var(--bg) 90%, transparent); backdrop-filter: blur(16px); }
.stdlib-search input { border-radius: 7px; background: var(--bg-input); }
.stdlib-result { margin: 0 2px 18px; color: var(--text-muted); font: 11px/1.5 var(--font-mono); }
.stdlib-result b { color: var(--text); }
.stdlib-ns { margin-bottom: 10px; padding: 22px; border-radius: 10px; border-color: var(--border); background: var(--bg-card); }
.stdlib-ns:hover { border-color: var(--line-strong); }
.stdlib-ns h3 { color: var(--text); font-size: 17px; }
.stdlib-ns-desc { color: var(--text-muted); }
.stdlib-fn-grid { gap: 5px; }
.stdlib-fn { padding: 5px 8px; border-radius: 4px; background: var(--bg-soft); border: 1px solid transparent; color: var(--text-soft); }
.stdlib-fn:hover { color: var(--text); border-color: var(--border); }

/* Downloads */
.dl-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.dl-card { padding: 26px; border-radius: 10px; border-color: var(--border); background: var(--bg-card); }
.dl-card:hover { border-color: var(--line-strong); transform: none; }
.dl-card h3 { color: var(--text); }
.dl-size { color: var(--text-muted); }

/* Extensions */
.ext-hero .ext-kicker { color: var(--brand); font: 650 11px/1.2 var(--font-mono); letter-spacing: .12em; }
.ext-hero h1 { font-size: clamp(40px, 5vw, 62px); }
.ext-hero-import { margin-top: 22px; border-radius: 7px; background: var(--bg-code); }
.ext-hero-stats { justify-content: flex-start; }
.ext-stat-pill { border-radius: 5px; background: var(--bg-card); }
.ext-layout { max-width: var(--max-w); padding: 34px 24px 100px; }
.ext-search { position: sticky; top: calc(var(--nav-h) + 10px); z-index: 20; padding: 10px; margin: 0 0 10px; border: 1px solid var(--border); border-radius: 10px; background: color-mix(in srgb, var(--bg) 90%, transparent); backdrop-filter: blur(16px); }
.ext-search input { border-radius: 7px; background: var(--bg-input); }
.ext-chip { border-radius: 5px; background: var(--bg-card); font-size: 12px; }
.ext-chip:hover { border-color: var(--line-strong); transform: none; }
.ext-chip.active { color: var(--on-brand); background: var(--brand); border-color: var(--brand); }
.ext-result-line { font-family: var(--font-mono); font-size: 11px; }
.ext-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 9px; }
.ext-card { min-height: 156px; padding: 18px; border-radius: 9px; border-color: var(--border); background: var(--bg-card); animation: none; }
.ext-card::before { width: 2px; opacity: .75; }
.ext-card:hover { border-color: var(--line-strong); transform: none; box-shadow: none; }
.ext-card:hover::before { width: 2px; }
.ext-name { color: var(--text); }
.ext-ver, .ext-dep.dep-has { border-radius: 4px; background: var(--bg-soft); }
.ext-dep.dep-zero { border-radius: 4px; }
.ext-doc { opacity: .7; transform: none; }
.extlib-layout { max-width: 940px; padding: calc(var(--nav-h) + 54px) 24px 105px; }
.extlib-title-row h1 { color: var(--text); font-size: clamp(34px, 5vw, 52px); letter-spacing: -.055em; }
.extlib-cat-badge, .extlib-badge { border-radius: 5px; }
.extlib-lead { max-width: 830px; }
.ext-tabs { position: sticky; top: var(--nav-h); z-index: 15; margin: 30px 0 38px; padding-top: 8px; background: var(--bg); }
.ext-tab { padding: 11px 18px; }
.ext-tab.active { color: var(--text); border-bottom-color: var(--brand); }
.ext-panel { animation: none; }
.ext-panel h2 { font-weight: 620; letter-spacing: -.025em; }
.ext-scene { border-radius: 5px; background: var(--bg-card); }
.ext-scene:hover { border-color: var(--line-strong); transform: none; }
.api-sig { border-left-width: 2px; border-radius: 8px; background: var(--bg-code); }
.api-group-title { color: var(--text); }
.ext-back { border-radius: 6px; background: var(--bg-card); }

/* Footer */
.footer { padding: 58px 24px 30px; border-top-color: var(--border); }
.footer-inner { max-width: var(--max-w); grid-template-columns: 2fr 1fr 1fr; gap: 50px; }
.footer-brand .brand-wordmark { margin-bottom: 15px; font-size: 24px; }
.footer-brand p { max-width: 410px; color: var(--text-muted); }
.footer-col h4 { color: var(--text); font: 650 10px/1.2 var(--font-mono); letter-spacing: .12em; }
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 7px; }
.footer-col a { display: inline-block; color: var(--text-muted); }
.footer-col a:hover { color: var(--text); }
.footer-bottom { max-width: var(--max-w); color: var(--text-muted); text-align: left; }

/* Search and utility */
.search-overlay { padding: 12vh 20px 20px; background: rgba(0, 0, 0, .65); backdrop-filter: blur(10px); }
.search-box { max-width: 680px; border-radius: 12px; background: var(--bg-card); border-color: var(--line-strong); }
.search-input { padding: 18px 20px; }
.search-result { border-color: var(--border); }
.search-result.is-selected, .search-result:hover { background: var(--bg-soft); }
.sr-title { color: var(--text); }
.back-top { right: 24px; bottom: 24px; width: 40px; height: 40px; border-radius: 8px; background: var(--bg-card); color: var(--text); border: 1px solid var(--border); box-shadow: none; }
.back-top:hover { background: var(--bg-soft); border-color: var(--line-strong); transform: none; }

@media (max-width: 1080px) {
  .nav-inner { padding-inline: 22px; }
  .nav-links { gap: 1px; }
  .nav-links a { padding-inline: 7px; }
  .hero-raycast { grid-template-columns: minmax(0, 1fr); min-height: auto; gap: 56px; padding: calc(var(--nav-h) + 68px) 7vw 80px; }
  .hero-copy, .command-stage { width: min(100%, 760px); margin: 0 auto; }
  .hero h1.brand-display { font-size: clamp(100px, 18vw, 142px); }
  .platform-advantage { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .ext-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 900px) {
  .nav-links {
    position: fixed; top: var(--nav-h); left: 0; right: 0; max-height: calc(100vh - var(--nav-h));
    display: none; overflow-y: auto; padding: 14px 20px 24px; border-bottom: 1px solid var(--border);
    background: var(--bg); box-shadow: 0 24px 50px rgba(0,0,0,.3);
  }
  .nav-links.nav-open { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 5px; }
  .nav-links a { padding: 12px; border: 1px solid var(--border); border-radius: 7px; background: var(--bg-card); }
  .nav-links a[aria-current="page"]::after { display: none; }
  .nav-actions { margin-left: auto; }
  .nav-toggle { display: flex; }
  .page-header { padding-top: calc(var(--nav-h) + 54px); }
  .tour-layout { grid-template-columns: 1fr; gap: 24px; }
  .tour-sidebar { display: none; position: fixed; inset: var(--nav-h) 0 0; z-index: 80; max-height: none; padding: 20px 24px 50px; overflow-y: auto; background: var(--bg); }
  .tour-sidebar.toc-mobile-open { display: block; }
  .toc-mobile-btn { position: sticky; top: calc(var(--nav-h) + 10px); z-index: 70; display: inline-flex; width: max-content; padding: 8px 14px; border: 1px solid var(--border); border-radius: 7px; background: var(--bg-card); color: var(--text); }
  .book-path { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1.5fr 1fr 1fr; gap: 28px; }
}

@media (max-width: 680px) {
  :root { --nav-h: 62px; }
  body { font-size: 14px; }
  .nav-inner { padding-inline: 16px; }
  .nav-logo { font-size: 20px; }
  .theme-toggle, .search-toggle, .nav-toggle { width: 34px; height: 34px; }
  .nav-links.nav-open { grid-template-columns: 1fr; }
  .hero-raycast { padding: calc(var(--nav-h) + 48px) 20px 64px; gap: 42px; }
  .hero-badge { margin-bottom: 26px; font-size: 9px; }
  .hero h1.brand-display { font-size: clamp(76px, 26vw, 104px); }
  .hero-tagline { font-size: clamp(25px, 8vw, 32px); }
  .hero-desc { font-size: 14px; }
  .hero-actions { gap: 18px; }
  .hero-metrics { margin-top: 42px; }
  .hero-metrics strong { font-size: 10px; }
  .hero-metrics span { font-size: 9px; }
  .command-topbar { grid-template-columns: 1fr auto; }
  .command-topbar > span { display: none; }
  .command-search { height: 68px; padding-inline: 17px; font-size: 14px; }
  .command-results { padding: 7px; }
  .command-item { min-height: 62px; grid-template-columns: 38px 1fr; gap: 10px; padding: 8px; }
  .command-item kbd { display: none; }
  .command-icon { width: 36px; height: 28px; }
  .terminal-strip { height: 50px; padding-inline: 14px; }
  .terminal-meta { display: none; }
  .section, .platform-section { padding: 72px 20px; }
  .section-title { font-size: 32px; }
  .hl-grid-editorial, .feature-grid, .std-grid, .platform-advantage, .ext-grid, .dl-grid, .api-grid { grid-template-columns: 1fr; }
  .hl-card { min-height: auto; }
  .page-header { margin-inline: 20px; padding: calc(var(--nav-h) + 44px) 0 42px; }
  .page-header h1 { font-size: 38px; }
  .page-content, .tour-layout, .stdlib-layout, .ext-layout, .extlib-layout { padding-left: 20px; padding-right: 20px; }
  .tour-nav, .ch-prevnext, .chapter-nav { grid-template-columns: 1fr; }
  .stdlib-search, .ext-search { margin-inline: -8px; }
  .ext-hero-import { max-width: 100%; overflow-x: auto; white-space: nowrap; }
  .ext-stat-pill { padding: 5px 9px; }
  .extlib-title-row h1 { word-break: break-word; }
  .ext-tabs { margin-inline: -20px; padding-left: 8px; }
  .ext-kv { display: block; overflow-x: auto; }
  .footer { padding-inline: 20px; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}