:root {
  --graphite: #172028;
  --graphite-2: #22303a;
  --paper: #f4f7f8;
  --paper-deep: #e8eef0;
  --white: #ffffff;
  --ink: #19242c;
  --muted: #53666f;
  --line: #cbd6da;
  --blue: #236f8f;
  --blue-soft: #dcecf2;
  --amber: #8a5a00;
  --amber-soft: #fbf0d8;
  --green: #2f6d53;
  --green-soft: #e0eee7;
  --violet: #6d5a9a;
  --violet-soft: #ece8f4;
  --teal: #247f7b;
  --teal-soft: #dff0ee;
  --copper: #82451f;
  --copper-soft: #f4e7df;
  --red: #a13f3f;
  --red-soft: #f6e3e3;
  --body-font: "Pretendard Variable", "SUIT Variable", "Noto Sans KR", "Malgun Gothic", sans-serif;
  --display-font: "Bahnschrift Condensed", "Arial Narrow", "Malgun Gothic", sans-serif;
  --mono-font: "Cascadia Mono", "JetBrains Mono", Consolas, monospace;
  --sidebar: 252px;
  --context: 252px;
  --content: 820px;
}

* { box-sizing: border-box; }
html { scroll-behavior: auto; scroll-padding-top: 28px; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--body-font); font-size: 17px; line-height: 1.78; word-break: keep-all; overflow-wrap: break-word; }
a { color: var(--blue); text-underline-offset: 3px; }
button, input { font: inherit; }
.skip-link { position: fixed; z-index: 1000; top: 8px; left: 8px; padding: 8px 12px; color: white; background: var(--graphite); transform: translateY(-150%); }
.skip-link:focus { transform: translateY(0); }
.mobile-bar { display: none; }

.sidebar { position: fixed; z-index: 20; inset: 0 auto 0 0; width: var(--sidebar); display: flex; flex-direction: column; background: var(--graphite); color: #dce5e8; border-right: 1px solid #31404a; }
.brand { display: grid; padding: 32px 24px 28px; color: white; text-decoration: none; border-bottom: 1px solid #31404a; }
.brand span { color: #7fc1dc; font: 700 12px/1.2 var(--mono-font); letter-spacing: .13em; }
.brand b { margin-top: 8px; font: 750 27px/1.05 var(--display-font); letter-spacing: -.03em; }
.brand small { margin-top: 8px; color: #9fb1ba; font-size: 12px; }
.site-search { position: relative; display: grid; gap: 6px; margin: 18px 18px 12px; }
.site-search span { color: #90a7b1; font-size: 11px; letter-spacing: .08em; }
.site-search input { width: 100%; padding: 10px 48px 10px 11px; color: white; background: #10181d; border: 1px solid #3c4c56; border-radius: 2px; outline: none; }
.site-search input:focus { border-color: #6eb4d0; box-shadow: 0 0 0 2px rgb(43 126 161 / .3); }
.site-search kbd { position: absolute; right: 8px; bottom: 9px; padding: 1px 5px; color: #8fa3ac; border: 1px solid #44545d; border-radius: 2px; font: 10px/1.5 var(--mono-font); }
.search-results { position: absolute; z-index: 4; top: 145px; left: 18px; right: 18px; max-height: calc(100vh - 170px); overflow: auto; background: #10181d; border: 1px solid #43535d; box-shadow: 0 18px 40px rgb(0 0 0 / .35); }
.search-results a { display: grid; padding: 11px 12px; color: white; text-decoration: none; border-bottom: 1px solid #283740; }
.search-results a:hover, .search-results a:focus { background: #243640; }
.search-results span { color: #75b5cf; font: 11px/1.4 var(--mono-font); }
.search-results b { margin-top: 2px; font-size: 13px; }
.search-results small { color: #9fb1ba; font-size: 11px; }
.chapter-nav { flex: 1; overflow-y: auto; padding: 5px 10px 22px; scrollbar-width: thin; }
.chapter-nav a { display: grid; grid-template-columns: 28px 1fr; align-items: center; min-height: 44px; padding: 7px 10px; color: #c4d0d5; text-decoration: none; border-left: 2px solid transparent; }
.chapter-nav a span { color: #78929d; font: 12px/1 var(--mono-font); }
.chapter-nav a b { font-size: 13px; font-weight: 600; }
.chapter-nav a:hover { color: white; background: #1d2a32; }
.chapter-nav a.is-active { color: white; background: #223945; border-left-color: #5cb1d3; }
.chapter-nav a.is-active span { color: #72c2e1; }
.nav-level { margin: 16px 10px 5px; color: #78909b; font: 700 9px/1 var(--mono-font); letter-spacing: .16em; text-transform: uppercase; }
.nav-level:first-child { margin-top: 4px; }
.nav-level-intermediate { color: #d7ad61; }
.nav-level-senior { color: #77bad5; }
.nav-level-master { color: #82b99f; }
.nav-level-broadcast { color: #b9a9dc; }
.nav-level-practice { color: #75c8c2; }
.nav-level-field { color: #d5a080; }
.sidebar footer { padding: 14px 24px 20px; color: #8099a3; border-top: 1px solid #31404a; font: 10px/1.5 var(--mono-font); }
.sidebar footer p { margin: 2px 0; }

#book { margin-left: var(--sidebar); margin-right: var(--context); min-width: 0; }
.hero, .chapter { width: min(100%, 1100px); margin: 0 auto; }
.hero { min-height: 100vh; display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(260px, .7fr); align-content: center; gap: 42px 56px; padding: 72px clamp(32px, 5vw, 84px); background-image: linear-gradient(90deg, transparent 49px, rgb(43 126 161 / .07) 50px, transparent 51px); background-size: 72px 100%; }
.hero-copy .eyebrow, .chapter-kicker { margin: 0 0 18px; color: var(--blue); font: 700 12px/1.2 var(--mono-font); letter-spacing: .13em; }
.hero h1 { max-width: 760px; margin: 0; font: 760 clamp(48px, 5.5vw, 83px)/.98 var(--display-font); letter-spacing: -.055em; }
.hero h1 em { color: var(--blue); font-style: normal; }
.hero-copy > p:last-of-type { max-width: 650px; margin: 28px 0 0; color: #455761; font-size: 20px; }
.hero-actions { display: flex; gap: 10px; margin-top: 32px; }
.hero-actions a { padding: 10px 18px; color: white; background: var(--graphite); text-decoration: none; border: 1px solid var(--graphite); }
.hero-actions a + a { color: var(--graphite); background: transparent; }
.hero-method { align-self: end; padding: 22px; background: var(--graphite); color: white; box-shadow: 14px 14px 0 var(--blue-soft); }
.hero-method > b { color: #91cee5; font: 700 12px/1.2 var(--mono-font); letter-spacing: .08em; }
.hero-method ol { padding: 0; margin: 18px 0 0; list-style: none; }
.hero-method li { display: grid; grid-template-columns: 32px 1fr; gap: 8px; padding: 11px 0; border-top: 1px solid #364651; font-size: 14px; line-height: 1.45; }
.hero-method li span { color: #79bad3; font: 12px/1.5 var(--mono-font); }
.hero .diagram { grid-column: 1 / -1; margin: 6px 0 0; }
.course-launch { grid-column: 1 / -1; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border: 1px solid var(--line); background: rgb(255 255 255 / .58); }
.course-launch a { --route-color: var(--graphite); position: relative; display: grid; align-content: start; min-height: 190px; padding: 22px; color: var(--ink); text-decoration: none; border-right: 1px solid var(--line); border-top: 4px solid var(--route-color); }
.course-launch a:nth-child(4n) { border-right: 0; }
.course-launch a:hover, .course-launch a:focus { z-index: 1; background: white; box-shadow: 0 0 0 2px var(--route-color); outline: 0; }
.course-launch span { color: var(--muted); font: 700 10px/1.2 var(--mono-font); letter-spacing: .08em; }
.course-launch b { margin-top: 13px; font: 760 27px/1 var(--display-font); }
.course-launch p { margin: 12px 0 18px; color: #52636c; font-size: 13px; line-height: 1.55; }
.course-launch em { align-self: end; color: var(--muted); font: 10px/1.4 var(--mono-font); font-style: normal; }
.course-launch-service, .course-launch-wing, .course-launch-systems { --route-color: var(--blue) !important; }
.course-launch-mixing { --route-color: var(--amber) !important; }
.course-launch-broadcast { --route-color: var(--violet) !important; }
.course-launch-master { --route-color: var(--green) !important; }
.course-launch-field { --route-color: var(--copper) !important; }
.part-launch { grid-column: 1 / -1; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); border: 1px solid var(--line); background: #f7fafb; }
.part-launch a { position: relative; display: grid; min-height: 146px; padding: 20px 22px; color: var(--ink); text-decoration: none; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.part-launch a:nth-child(3n) { border-right: 0; }
.part-launch a:nth-last-child(-n+3) { border-bottom: 0; }
.part-launch a:hover, .part-launch a:focus-visible { z-index: 1; background: white; box-shadow: inset 0 0 0 2px var(--blue); outline: 0; }
.part-launch span { color: var(--blue); font: 700 11px/1 var(--mono-font); }
.part-launch b { margin-top: 11px; font: 720 22px/1.05 var(--display-font); }
.part-launch small { margin-top: 8px; color: #5b6c74; font-size: 12px; line-height: 1.5; }
.part-launch em { align-self: end; margin-top: 16px; color: var(--muted); font: 10px/1.2 var(--mono-font); font-style: normal; }

.part-masthead { width: min(100%, 1100px); margin: 0 auto; padding: 72px clamp(32px, 5vw, 84px) 54px; border-bottom: 1px solid var(--line); background: linear-gradient(90deg, transparent 49px, rgb(43 126 161 / .07) 50px, transparent 51px); background-size: 72px 100%; }
.part-masthead > p { margin: 0 0 12px; color: var(--blue); font: 700 11px/1.2 var(--mono-font); letter-spacing: .12em; }
.part-masthead > h1 { max-width: 760px; margin: 0; font: 760 clamp(42px, 5vw, 70px)/1 var(--display-font); letter-spacing: -.045em; }
.part-masthead > span { display: block; max-width: 700px; margin-top: 18px; color: #51636c; font-size: 17px; line-height: 1.55; }
.part-masthead nav { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); margin-top: 34px; border: 1px solid var(--line); background: rgb(255 255 255 / .7); }
.part-masthead nav a { display: grid; grid-template-columns: 28px 1fr; gap: 8px; padding: 14px; color: var(--graphite); border-right: 1px solid var(--line); text-decoration: none; font-size: 12px; line-height: 1.4; }
.part-masthead nav a:last-child { border-right: 0; }
.part-masthead nav a:hover, .part-masthead nav a:focus-visible { color: var(--blue); background: white; outline: 2px solid var(--blue); outline-offset: -2px; }
.part-masthead nav span { color: var(--blue); font: 700 11px/1.5 var(--mono-font); }
.page-part-overview #book { margin-right: 0; }
.page-part-overview .context-rail { display: none; }
.evidence-strip { grid-column: 1 / -1; display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.evidence-strip div { display: grid; padding: 18px 22px; border-right: 1px solid var(--line); }
.evidence-strip div:last-child { border-right: 0; }
.evidence-strip b { color: var(--graphite); font: 750 30px/1 var(--display-font); }
.evidence-strip span { margin-top: 5px; color: var(--muted); font-size: 12px; }

.curriculum-hub { background: #edf3f5; }
.curriculum-header { max-width: 880px; }
.curriculum-body { max-width: 960px; }
.curriculum-section-header { margin: 82px 0 24px; padding-top: 20px; border-top: 2px solid var(--graphite); }
.curriculum-section-header:first-child { margin-top: 0; }
.curriculum-section-header > p { margin: 0 0 10px; color: var(--blue); font: 700 10px/1.2 var(--mono-font); letter-spacing: .13em; }
.curriculum-section-header h2 { margin: 0; font: 750 34px/1.15 var(--display-font); letter-spacing: -.025em; }
.curriculum-section-header > span { display: block; max-width: 720px; margin-top: 10px; color: var(--muted); font-size: 14px; line-height: 1.6; }

.level-ladder { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 1px; margin: 0; padding: 0; background: var(--line); list-style: none; }
.level-ladder li { min-width: 0; margin: 0; padding: 17px 15px 19px; background: white; border-top: 5px solid var(--graphite); }
.level-ladder li[data-level="L2"], .level-ladder li[data-level="L4"] { border-top-color: var(--blue); }
.level-ladder li[data-level="L3"] { border-top-color: var(--amber); }
.level-ladder li[data-level="L5"] { border-top-color: var(--green); }
.level-ladder span { color: var(--muted); font: 700 10px/1 var(--mono-font); }
.level-ladder b { display: block; margin-top: 11px; font: 750 22px/1 var(--display-font); }
.level-ladder p { margin: 10px 0 0; color: #53646d; font-size: 12px; line-height: 1.55; }

.course-quick-nav { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1px; margin: 28px 0 0; background: var(--line); border: 1px solid var(--line); }
.course-quick-nav a { display: grid; min-height: 72px; align-content: center; padding: 12px 15px; color: var(--ink); background: #f7fafb; text-decoration: none; }
.course-quick-nav a:hover, .course-quick-nav a:focus { z-index: 1; background: white; box-shadow: inset 0 0 0 2px var(--blue); outline: none; }
.course-quick-nav span { color: var(--muted); font: 700 9px/1.2 var(--mono-font); letter-spacing: .08em; }
.course-quick-nav b { margin-top: 7px; font-size: 13px; }

.course-route { --route-color: var(--graphite); margin: 0 0 14px; background: white; border: 1px solid var(--line); border-left: 6px solid var(--route-color); }
.course-route-service, .course-route-wing, .course-route-systems { --route-color: var(--blue); }
.course-route-mixing { --route-color: var(--amber); }
.course-route-broadcast { --route-color: var(--violet); }
.course-route-master { --route-color: var(--green); }
.course-route-field { --route-color: var(--copper); }
.course-route > summary { display: grid; grid-template-columns: 78px 1fr auto 16px; gap: 16px; align-items: center; min-height: 92px; padding: 17px 20px; cursor: pointer; list-style: none; }
.course-route > summary::-webkit-details-marker { display: none; }
.course-route > summary::after { grid-column: 4; grid-row: 1; align-self: center; color: var(--route-color); content: "+"; font: 700 22px/1 var(--mono-font); }
.course-route[open] > summary::after { content: "−"; }
.course-code { color: var(--route-color); font: 700 11px/1.2 var(--mono-font); letter-spacing: .1em; }
.course-summary-copy { display: grid; }
.course-summary-copy b { font: 750 24px/1.1 var(--display-font); }
.course-summary-copy small { margin-top: 7px; color: var(--muted); font-size: 12px; line-height: 1.45; }
.course-route > summary > em { grid-column: 3; color: var(--muted); font: 10px/1.4 var(--mono-font); font-style: normal; white-space: nowrap; }
.course-route[open] > summary { background: #f4f8f9; border-bottom: 1px solid var(--line); }
.course-route-body { padding: 22px; }
.course-gate { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; margin-bottom: 20px; background: var(--line); }
.course-gate p { margin: 0; padding: 14px 16px; background: #edf3f5; font-size: 12px; line-height: 1.55; }
.course-gate span { display: block; margin-bottom: 6px; color: var(--route-color); font: 700 9px/1.2 var(--mono-font); letter-spacing: .08em; }
.course-modules { display: grid; gap: 10px; margin: 0; padding: 0; list-style: none; }
.course-module { display: grid; grid-template-columns: 56px minmax(0, 1fr); margin: 0; background: white; border: 1px solid var(--line); }
.module-code { display: grid; place-items: start center; padding-top: 20px; color: var(--route-color); background: #edf3f5; font: 700 11px/1 var(--mono-font); }
.module-copy { padding: 16px 18px 18px; }
.module-meta { display: flex; flex-wrap: wrap; gap: 8px 12px; margin: 0 0 9px; color: var(--muted); font: 9px/1.4 var(--mono-font); }
.module-meta span { color: var(--route-color); font-weight: 700; }
.module-meta em { font-style: normal; }
.module-copy h3 { margin: 0; font-size: 18px; line-height: 1.35; }
.module-copy > p:not(.module-meta) { margin: 8px 0 14px; color: #4f6069; font-size: 13px; line-height: 1.6; }
.module-copy dl { display: grid; grid-template-columns: 1fr 1.35fr; gap: 1px; margin: 0; background: var(--line); }
.module-copy dl > div { padding: 12px 13px; background: #f7fafb; }
.module-copy dt { color: var(--muted); font: 700 9px/1.2 var(--mono-font); }
.module-copy dd { margin: 6px 0 0; font-size: 12px; line-height: 1.55; }
.prereq-link { color: var(--route-color); font: 700 .95em/1.2 var(--mono-font); text-decoration: underline; text-decoration-color: color-mix(in srgb, var(--route-color) 45%, transparent); text-underline-offset: 3px; }
.prereq-link:hover, .prereq-link:focus-visible { color: var(--ink); text-decoration-color: currentColor; outline: none; }
.module-sources { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; margin-top: 12px; }
.module-sources span { color: var(--muted); font: 700 9px/1 var(--mono-font); }
.module-sources a { padding: 4px 8px; color: var(--route-color); background: #edf3f5; font-size: 10px; line-height: 1.4; text-decoration: none; }
.module-sources a::after { margin-left: 5px; content: "→"; font-family: var(--mono-font); }
.module-sources a:hover, .module-sources a:focus { box-shadow: inset 0 0 0 1px var(--route-color); outline: none; }

.reference-shelf > div { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: var(--line); border: 1px solid var(--line); }
.reference-shelf > div > a { display: grid; min-height: 105px; align-content: center; padding: 17px 20px; color: var(--ink); background: white; text-decoration: none; }
.reference-shelf > div > a:hover, .reference-shelf > div > a:focus { z-index: 1; box-shadow: inset 0 0 0 2px var(--graphite); outline: none; }
.reference-shelf b { font-size: 15px; }
.reference-shelf span { margin-top: 7px; color: var(--muted); font-size: 12px; line-height: 1.55; }

.procedure-warning { margin: 0 0 18px; padding: 18px 20px; color: #673535; background: var(--red-soft); border-left: 5px solid var(--red); }
.procedure-warning b { font: 750 18px/1.2 var(--display-font); }
.procedure-warning p { margin: 7px 0 0; font-size: 13px; line-height: 1.6; }
.wing-procedure-list { border-top: 2px solid var(--graphite); }
.wing-procedure-card { background: white; border-bottom: 1px solid var(--line); }
.wing-procedure-card > summary { display: grid; grid-template-columns: 58px 1fr 88px 200px; gap: 10px; align-items: center; min-height: 72px; padding: 12px 14px; cursor: pointer; list-style: none; }
.wing-procedure-card > summary::-webkit-details-marker { display: none; }
.wing-procedure-card > summary > span { color: var(--blue); font: 700 10px/1 var(--mono-font); }
.wing-procedure-card > summary > b { font-size: 14px; line-height: 1.4; }
.wing-procedure-card > summary > em { color: var(--muted); font: 9px/1.3 var(--mono-font); font-style: normal; }
.wing-procedure-card > summary > small { color: #53646d; font-size: 11px; line-height: 1.4; }
.wing-procedure-card > summary::after { color: var(--blue); content: "+"; font: 700 16px/1 var(--mono-font); }
.wing-procedure-card > summary { grid-template-columns: 58px minmax(0, 1fr) 88px 200px 16px; }
.wing-procedure-card[open] > summary { background: var(--blue-soft); }
.wing-procedure-card[open] > summary::after { content: "−"; }
.procedure-body { padding: 19px 22px 24px 72px; }
.procedure-purpose { margin: 0 0 14px; font-weight: 700; }
.procedure-body dl { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; margin: 0; background: var(--line); }
.procedure-body dl > div { padding: 13px 14px; background: #f7fafb; }
.procedure-body dt { color: var(--blue); font: 700 9px/1.2 var(--mono-font); }
.procedure-body dd { margin: 6px 0 0; font-size: 12px; line-height: 1.6; }
.procedure-body code { padding: 2px 5px; color: #15546d; background: var(--blue-soft); font: 10px/1.5 var(--mono-font); }
.procedure-body dl > div:nth-last-child(2) { grid-column: 1 / -1; }
.procedure-body .procedure-caveat { grid-column: 1 / -1; background: var(--amber-soft); }
.procedure-body .procedure-caveat dt { color: #795014; }

.chapter { padding: 100px clamp(32px, 5vw, 84px) 72px; border-top: 1px solid var(--line); }
.chapter-header { margin-bottom: 68px; }
.chapter-level { display: inline-block; margin: 0 0 14px; padding: 5px 9px; color: white; background: var(--graphite); font: 700 10px/1 var(--mono-font); letter-spacing: .12em; }
.chapter-level-intermediate { color: #4f3108; background: var(--amber-soft); border: 1px solid #dfb360; }
.chapter-level-senior { color: #16556e; background: var(--blue-soft); border: 1px solid #83bdd3; }
.chapter-level-master { color: #225943; background: var(--green-soft); border: 1px solid #7bb095; }
.chapter-level-broadcast { color: #4d3a7c; background: var(--violet-soft); border: 1px solid #a99bc8; }
.chapter-level-practice { color: #145c59; background: var(--teal-soft); border: 1px solid #7ab9b4; }
.chapter-level-field { color: #703817; background: var(--copper-soft); border: 1px solid #c99a7e; }
.chapter-header h1, .curriculum-header h2 { max-width: 800px; margin: 0; font: 760 clamp(43px, 5vw, 68px)/1.02 var(--display-font); letter-spacing: -.045em; }
.chapter-header > p:not(.chapter-kicker):not(.chapter-position):not(.chapter-level) { max-width: 720px; color: var(--muted); font-size: 18px; }
.chapter-position { margin: 32px 0 8px; color: var(--muted); font: 11px/1.4 var(--mono-font); letter-spacing: .08em; }
.chapter-body { max-width: var(--content); }
.chapter-body > h2, .chapter-lesson > h2 { margin: 88px 0 24px; padding-top: 20px; border-top: 2px solid var(--graphite); font: 750 34px/1.15 var(--display-font); letter-spacing: -.025em; }
.chapter-body > h2:first-child, .chapter-lesson > h2:first-of-type { margin-top: 0; }
.chapter-body h3 { margin: 46px 0 16px; font-size: 23px; line-height: 1.35; letter-spacing: -.02em; }
.chapter-body h4 { margin: 32px 0 12px; font-size: 18px; }
.chapter-body h2:focus, .chapter-body h3:focus, .chapter-body h4:focus { outline: none; }
.heading-anchor { margin-left: .4em; color: transparent; font: 400 14px/1 var(--mono-font); text-decoration: none; }
h2:hover .heading-anchor, h3:hover .heading-anchor, .heading-anchor:focus { color: var(--blue); }
.chapter-body p { margin: 0 0 18px; }
.chapter-body li { margin: 5px 0; }
.chapter-body strong { font-weight: 750; }
.chapter-body code { padding: .1em .32em; color: #185d79; background: var(--blue-soft); border-radius: 2px; font: .88em/1.4 var(--mono-font); word-break: break-word; }
.claim-badge { display: inline-block; margin: 0 .14em; padding: .18em .42em .2em; color: #23424f; background: #e7eef1; border: 1px solid #afc0c8; border-left-width: 3px; font: 700 .7em/1.25 var(--mono-font); letter-spacing: -.02em; vertical-align: .12em; white-space: nowrap; }
.claim-plus { color: var(--muted); font: 700 .65em/1 var(--mono-font); vertical-align: .16em; }
.claim-fact { color: #16556e; background: var(--blue-soft); border-color: #83bdd3; }
.claim-wing { color: #4d3a7c; background: var(--violet-soft); border-color: #a99bc8; }
.claim-practice { color: #225943; background: var(--green-soft); border-color: #7bb095; }
.claim-conditional { color: #6e4a14; background: var(--amber-soft); border-color: #dfb360; }
.claim-workflow { color: #3f5661; background: #edf3f5; border-color: #aebfc7; }
.claim-disputed, .claim-terminology { color: #703817; background: var(--copper-soft); border-color: #c99a7e; }
.claim-safety { color: #7a2d2d; background: var(--red-soft); border-color: #d99a9a; }
.chapter-body pre { margin: 28px 0; padding: 20px; overflow-x: auto; color: #d9e5e9; background: var(--graphite); border-left: 4px solid var(--blue); }
.chapter-body pre code { padding: 0; color: inherit; background: transparent; font-size: 13px; line-height: 1.7; white-space: pre; }
.chapter-body hr { height: 1px; margin: 72px 0; background: var(--line); border: 0; }
.chapter-body img { max-width: 100%; }
.chapter-body a { font-weight: 600; }

.lesson-console { max-width: var(--content); margin: 0 0 56px; padding-top: 18px; border-top: 5px solid var(--blue); }
.lesson-console > header { display: grid; gap: 8px; max-width: 700px; }
.lesson-console > header p { margin: 0; color: var(--blue); font: 700 10px/1.2 var(--mono-font); letter-spacing: .12em; }
.lesson-console > header h2 { margin: 0; font: 750 30px/1.12 var(--display-font); letter-spacing: -.025em; }
.lesson-console > header span { color: var(--muted); font-size: 14px; line-height: 1.6; }
.lesson-console nav { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)) 130px; margin-top: 24px; border: 1px solid var(--line); background: var(--line); gap: 1px; }
.lesson-console nav a, .lesson-console nav button { position: relative; min-width: 0; display: grid; align-content: start; min-height: 142px; padding: 15px 14px; color: var(--ink); background: #f7fafb; border: 0; border-top: 4px solid #9cacb3; text-align: left; text-decoration: none; cursor: pointer; }
.lesson-console nav a::after { position: absolute; right: -7px; top: 20px; z-index: 1; width: 13px; height: 13px; background: #f7fafb; border-top: 1px solid var(--line); border-right: 1px solid var(--line); transform: rotate(45deg); content: ""; }
.lesson-console nav a:last-of-type::after { display: none; }
.lesson-console nav a:hover, .lesson-console nav a:focus-visible, .lesson-console nav button:hover, .lesson-console nav button:focus-visible { z-index: 2; background: white; border-top-color: var(--blue); outline: 2px solid var(--blue); outline-offset: -2px; }
.lesson-console nav a[aria-current="step"] { z-index: 2; color: #123d4f; background: var(--blue-soft); border-top-color: var(--blue); box-shadow: inset 0 -3px 0 var(--blue); }
.lesson-console nav a[aria-current="step"]::after { background: var(--blue-soft); }
.lesson-console nav button[aria-pressed="true"] { color: white; background: var(--graphite); border-top-color: var(--amber); box-shadow: inset 0 -3px 0 var(--amber); }
.lesson-console nav span { color: var(--blue); font: 700 10px/1 var(--mono-font); letter-spacing: .08em; }
.lesson-console nav button span { color: var(--amber); }
.lesson-console nav b { margin-top: 12px; font-size: 14px; line-height: 1.35; }
.lesson-console nav small { margin-top: 9px; color: var(--muted); font-size: 10px; line-height: 1.5; }
.lesson-console nav button[aria-pressed="true"] small { color: #b9c8ce; }
.lesson-status { margin: 0; padding: 10px 12px; color: #51636c; background: #e7edef; font-size: 12px; line-height: 1.45; }
.lesson-status b { color: var(--green); font: 700 10px/1.2 var(--mono-font); }
.lesson-marker { display: grid; grid-template-columns: 58px 1fr; gap: 15px; align-items: start; margin: 0 0 34px; padding: 17px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.lesson-marker > span { color: var(--blue); font: 750 20px/1 var(--display-font); }
.lesson-marker > div { display: grid; gap: 5px; }
.lesson-marker b { font-size: 16px; line-height: 1.3; }
.lesson-marker small { color: var(--muted); font: 10px/1.5 var(--mono-font); }
.chapter-body.lesson-mode-ready .chapter-lesson { display: none; }
.chapter-body.lesson-mode-ready .chapter-lesson.is-active, .chapter-body.lesson-mode-ready.is-full-reference .chapter-lesson { display: block; }
.chapter-body.lesson-mode-ready.is-full-reference .chapter-lesson + .chapter-lesson { margin-top: 92px; }
.footnote-ref a { padding: 0 2px; color: var(--blue); font: 700 11px/1 var(--mono-font); text-decoration: none; }
.footnotes { margin-top: 72px; padding: 24px 28px; color: #4a5a63; background: #eaf0f2; border-top: 2px solid #8ba4af; font-size: 13px; }
.footnotes h2 { margin: 0 0 12px !important; padding: 0 !important; border: 0 !important; font-size: 22px !important; }
.footnotes ol { margin-bottom: 0; padding-left: 23px; }
.footnote-back { text-decoration: none; }

.table-wrap { max-width: 100%; margin: 28px 0 34px; overflow-x: auto; border-top: 2px solid var(--graphite); border-bottom: 1px solid var(--line); scrollbar-width: thin; }
table { width: 100%; min-width: 650px; border-collapse: collapse; font-size: 14px; line-height: 1.55; }
th, td { padding: 12px 13px; text-align: left; vertical-align: top; border-bottom: 1px solid var(--line); border-right: 1px solid #e0e6e8; }
th:last-child, td:last-child { border-right: 0; }
th { color: white; background: var(--graphite-2); font-weight: 700; }
tbody tr:nth-child(even) { background: #edf2f3; }

.callout { position: relative; margin: 30px 0; padding: 20px 24px 18px 28px; background: white; border: 0; border-left: 4px solid var(--blue); box-shadow: 0 1px 0 var(--line); }
.callout::before { display: block; margin-bottom: 8px; color: var(--blue); font: 700 10px/1 var(--mono-font); letter-spacing: .1em; content: "NOTE"; }
.callout p:last-child { margin-bottom: 0; }
.callout-field { background: var(--green-soft); border-color: var(--green); }
.callout-field::before { color: var(--green); content: "FIELD JUDGMENT"; }
.callout-wing { background: var(--blue-soft); }
.callout-wing::before { content: "WING / VERIFIED"; }
.callout-danger { background: var(--red-soft); border-color: var(--red); }
.callout-danger::before { color: var(--red); content: "CAUTION"; }

.signal-rail { display: grid; gap: 14px; }
.rail-node { position: relative; display: grid; grid-template-columns: 26px 1fr; gap: 0 8px; padding: 8px 10px; color: #4f626b; background: #e7edef; border-left: 3px solid #adbbc1; }
.rail-node .rail-index { grid-row: 1 / 3; color: #53666f; font: 11px/1.5 var(--mono-font); }
.rail-node strong { font: 700 13px/1.25 var(--display-font); letter-spacing: .03em; }
.rail-node small { font-size: 10px; line-height: 1.3; }
.rail-node.is-active { color: #153d4d; background: var(--blue-soft); border-left-color: var(--blue); }
.rail-arrow { display: none; }
.signal-rail-compact { grid-template-columns: repeat(5, 1fr); gap: 0; max-width: 820px; }
.signal-rail-compact .rail-node { min-width: 0; padding: 10px; border-left: 0; border-top: 3px solid #adbbc1; }
.signal-rail-compact .rail-node.is-active { border-top-color: var(--blue); }

.diagram { margin: 36px 0 46px; padding: clamp(18px, 3vw, 30px); background: white; border: 1px solid var(--line); box-shadow: 8px 8px 0 #dfe7e9; break-inside: avoid; }
.diagram figcaption { display: grid; gap: 4px; margin-bottom: 25px; padding-bottom: 16px; border-bottom: 1px solid var(--line); }
.diagram figcaption b { font: 750 24px/1.15 var(--display-font); }
.diagram figcaption span { color: var(--muted); font-size: 13px; }
.flow-chain { display: flex; align-items: stretch; overflow-x: hidden; padding-bottom: 8px; }
.flow-step { flex: 1 1 0; min-width: 0; min-height: 105px; display: grid; align-content: start; padding: 9px 7px; background: #edf3f5; border-top: 3px solid var(--blue); }
.flow-step span { color: var(--muted); font: 10px/1.2 var(--mono-font); }
.flow-step strong { overflow-wrap: anywhere; margin-top: 10px; font: 700 13px/1.2 var(--display-font); }
.flow-step small { margin-top: 5px; color: var(--muted); font-size: 10px; line-height: 1.35; }
.flow-arrow { flex: 0 0 14px; align-self: center; color: var(--blue); font-style: normal; text-align: center; }
.path-compare { display: grid; gap: 10px; }
.path-row { display: grid; grid-template-columns: 94px minmax(90px, 1fr) 22px minmax(90px, 1fr) 22px minmax(100px, 1fr); align-items: center; gap: 6px; padding: 13px; background: #eef3f4; }
.path-row > b { font-size: 12px; }
.path-row > span { padding: 8px; text-align: center; background: white; border: 1px solid #c7d3d7; font: 12px/1.4 var(--mono-font); }
.path-row > i { color: var(--blue); font-style: normal; text-align: center; }
.path-row > em { grid-column: 2 / -1; color: var(--muted); font-size: 12px; font-style: normal; }
.path-row .path-control { color: white; background: var(--blue); border-color: var(--blue); }

.split-diagram { display: grid; grid-template-columns: 1fr 1.35fr; gap: 26px; }
.split-diagram figcaption { grid-column: 1 / -1; }
.meter-scale { position: relative; height: 360px; margin: 8px 16px 0; background: linear-gradient(to top, #4d8d71 0 48%, #d7a13b 48% 73%, #c65c53 73% 100%); border: 1px solid #afbec4; }
.meter-scale .signal-fill { position: absolute; inset: 70% 0 0; background: rgb(255 255 255 / .72); border-top: 3px solid var(--ink); }
.meter-scale .ceiling { position: absolute; z-index: 2; top: -9px; left: 12px; padding: 2px 6px; color: white; background: var(--red); font: 10px/1.5 var(--mono-font); }
.meter-scale .headroom-space { position: absolute; z-index: 2; inset: 54px 14px 29% 14px; display: grid; place-content: center; text-align: center; color: #6b4310; background: rgb(255 255 255 / .88); border: 1px dashed #a46f16; }
.meter-scale .headroom-space b { font: 750 18px/1 var(--display-font); }
.meter-scale .headroom-space small { margin-top: 7px; font-size: 10px; }
.meter-scale .current-peak { position: absolute; z-index: 3; right: 8px; bottom: 26%; padding: 3px 7px; color: white; background: var(--ink); font: 10px/1.5 var(--mono-font); }
.meter-panel p { margin: 14px 12px 0; color: var(--muted); font-size: 11px; line-height: 1.55; }
.wave-panel { align-self: center; }
.wave-panel svg { width: 100%; height: auto; }
.wave-panel text { fill: var(--muted); font: 14px var(--body-font); }
.ceiling-line { stroke: var(--red); stroke-width: 1.5; stroke-dasharray: 5 5; }
.wave-ok { fill: none; stroke: var(--blue); stroke-width: 5; }
.wave-clip { fill: none; stroke: var(--red); stroke-width: 5; }

.distance-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.distance-grid section { padding: 18px; background: #edf3f5; }
.distance-grid h3 { margin: 0 0 18px; font: 700 18px/1.2 var(--display-font); }
.distance-grid ul { margin: 16px 0 0; padding-left: 20px; font-size: 13px; }
.mic-scene { position: relative; display: grid; grid-template-columns: 36px 1fr 46px; align-items: center; gap: 8px; min-height: 108px; padding-bottom: 22px; }
.mic-scene .mouth, .mic-scene .mic { display: grid; place-items: center; aspect-ratio: 1; background: var(--graphite); color: white; border-radius: 50%; font: 10px/1 var(--mono-font); }
.mic-scene .voice { height: 10px; background: var(--blue); clip-path: polygon(0 35%, 88% 35%, 88% 0, 100% 50%, 88% 100%, 88% 65%, 0 65%); color: transparent; }
.mic-scene .ambient { position: absolute; right: 0; bottom: 2px; color: var(--amber); font-size: 11px; font-style: normal; border-bottom: 2px dashed var(--amber); }
.mic-scene.far { grid-template-columns: 36px 1fr 46px; gap: 26px; }
.mic-scene.far .voice { height: 5px; opacity: .72; }
.mic-scene.far .ambient { border-bottom-width: 5px; }

.polar-diagram svg { width: 100%; max-height: 300px; }
.polar-grid { fill: none; stroke: #ced9dd; stroke-width: 1; }
.polar-main { fill: rgb(43 126 161 / .18); stroke: var(--blue); stroke-width: 3; }
.polar-axis { fill: none; stroke: var(--blue); stroke-width: 3; marker-end: none; }
.polar-rear { fill: none; stroke: var(--red); stroke-width: 2; stroke-dasharray: 5 5; }
.mic-dot { fill: var(--graphite); }
.polar-diagram svg text { fill: var(--muted); font: 11px var(--body-font); }
.polar-diagram p { color: var(--muted); font-size: 12px; }
.wedge-map { position: relative; min-height: 300px; display: grid; place-items: center; background: #edf3f5; border: 1px solid #d6e0e3; }
.wedge-map .performer { position: absolute; top: 26px; font-weight: 700; }
.wedge-map .mic-icon { padding: 7px 10px; background: var(--graphite); color: white; font: 11px/1 var(--mono-font); }
.wedge-map .speaker-zone { position: absolute; right: 18px; top: 112px; color: white; background: var(--blue); padding: 10px; font-size: 11px; line-height: 1.3; }
.wedge-map .wedge { position: absolute; bottom: 88px; padding: 8px 15px; color: white; background: var(--amber); font: 11px/1 var(--mono-font); transform: skew(-10deg); }
.wedge-map .reject-line { position: absolute; bottom: 125px; height: 70px; border-left: 2px dashed var(--green); }
.wedge-map p { position: absolute; inset: auto 18px 12px; margin: 0; }

.bus-dca-grid { display: grid; gap: 18px; }
.audio-lanes { display: grid; grid-template-columns: repeat(3, minmax(74px, .7fr)) 100px minmax(100px, 1fr) 25px 78px 25px minmax(110px, 1fr); align-items: center; gap: 6px; }
.audio-lanes > span { padding: 8px; background: #eaf1f3; font: 11px/1.3 var(--mono-font); }
.audio-lanes > i { color: var(--blue); font-size: 11px; font-style: normal; text-align: center; }
.audio-lanes > b { padding: 11px; color: white; background: var(--blue); font: 13px/1.3 var(--display-font); text-align: center; }
.audio-lanes small { font-family: var(--body-font); font-size: 9px; font-weight: 400; }
.control-lane { display: grid; grid-template-columns: 130px 1fr; gap: 8px 12px; align-items: center; padding: 14px; background: var(--green-soft); border: 1px dashed var(--green); }
.control-lane b { color: var(--green); font: 700 16px/1 var(--display-font); }
.control-lane i { color: var(--green); font: 11px/1.4 var(--mono-font); font-style: normal; }
.control-lane span { grid-column: 2; color: var(--muted); font-size: 12px; }

.connection-grid { display: grid; gap: 12px; }
.connection-grid > div { display: flex; align-items: center; gap: 8px; min-height: 72px; padding: 12px; background: #edf3f5; }
.connection-grid b { flex: 0 0 130px; color: var(--muted); font-size: 12px; }
.connection-grid span, .connection-grid strong { padding: 9px 11px; color: var(--ink); background: white; border: 1px solid #c4d1d6; font: 12px/1.35 var(--mono-font); }
.connection-grid strong { color: white; background: var(--graphite); }
.connection-grid strong small { display: block; color: #9fb1ba; font: 9px/1.4 var(--body-font); }
.connection-grid i { color: var(--blue); font-size: 11px; font-style: normal; }
.connection-grid .speaker-level { color: var(--amber); font-weight: 700; }

.feedback-loop { display: flex; align-items: center; gap: 8px; padding: 22px; background: var(--red-soft); border: 1px solid #e0b8b8; }
.feedback-loop span { flex: 1; padding: 10px; color: white; background: var(--graphite); text-align: center; font: 12px/1.3 var(--mono-font); }
.feedback-loop i { color: var(--red); font-style: normal; }
.feedback-loop .loop-back { padding: 6px; border: 2px solid var(--red); border-radius: 50%; }
.two-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 14px; }
.two-actions p { margin: 0; padding: 14px; background: #eef3f4; font-size: 13px; }
.two-actions b { display: block; margin-bottom: 4px; color: var(--red); }

.checkpoint-chain { display: flex; align-items: stretch; gap: 6px; overflow-x: hidden; }
.checkpoint-chain button { flex: 1 1 112px; min-width: 0; min-height: 88px; padding: 11px; text-align: left; background: var(--green-soft); border: 1px solid #a9caba; cursor: pointer; }
.checkpoint-chain button.is-fault { background: var(--red-soft); border-color: #d9a8a8; }
.checkpoint-chain b { display: block; color: var(--green); font: 700 12px/1.3 var(--mono-font); }
.checkpoint-chain .is-fault b { color: var(--red); }
.checkpoint-chain small { display: block; margin-top: 9px; color: var(--muted); font-size: 10px; line-height: 1.4; }
.checkpoint-chain > i { align-self: center; color: var(--blue); font-style: normal; }
.checkpoint-answer { margin: 15px 0 0; padding: 11px 14px; color: var(--muted); background: #edf2f3; font-size: 12px; }

.reading-stack { --reading-accent: var(--graphite); margin: 30px 0 44px; border-top: 3px solid var(--reading-accent); background: white; box-shadow: 6px 6px 0 #dfe7e9; }
.reading-stack-reference { --reading-accent: var(--violet); }
.reading-stack-sequence { --reading-accent: var(--green); }
.reading-stack-diagnostic { --reading-accent: var(--amber); }
.reading-stack > header { display: flex; justify-content: space-between; gap: 16px; align-items: center; padding: 12px 16px; color: var(--muted); background: #eaf0f2; border-bottom: 1px solid var(--line); }
.reading-stack > header b { color: var(--reading-accent); font: 700 10px/1.3 var(--mono-font); letter-spacing: .08em; }
.reading-stack > header span { font-size: 11px; }
.reading-card { border-bottom: 1px solid var(--line); }
.reading-card:last-child { border-bottom: 0; }
.reading-card > summary { display: grid; grid-template-columns: minmax(0, 1fr) 28px; gap: 14px; align-items: center; min-height: 76px; padding: 15px 17px; cursor: pointer; list-style: none; }
.reading-card-sequence > summary { grid-template-columns: 46px minmax(0, 1fr) 28px; }
.reading-card-reference > summary { min-height: 58px; }
.reading-card-reference .reading-summary small { display: none; }
.reading-card > summary::-webkit-details-marker { display: none; }
.reading-card > summary::after { display: grid; place-items: center; width: 24px; height: 24px; color: var(--reading-accent); border: 1px solid currentColor; content: "+"; font: 16px/1 var(--mono-font); }
.reading-card[open] > summary { background: #f4f7f8; }
.reading-card[open] > summary::after { content: "−"; }
.reading-order { color: var(--reading-accent); font: 700 11px/1 var(--mono-font); }
.reading-summary { min-width: 0; display: grid; gap: 5px; }
.reading-summary b { font: 750 18px/1.28 var(--display-font); }
.reading-summary small { color: var(--muted); font-size: 12px; line-height: 1.5; }
.reading-card-body { padding: 0 17px 18px; background: #f4f7f8; }
.reading-card dl { margin: 0; border-top: 1px solid var(--line); }
.reading-card dl > div { display: grid; grid-template-columns: minmax(140px, .38fr) minmax(0, 1fr); gap: 18px; padding: 12px 0; border-bottom: 1px solid #dce4e7; }
.reading-card dl > div:last-child { border-bottom: 0; }
.reading-card dt { color: var(--reading-accent); font: 700 10px/1.45 var(--mono-font); }
.reading-card dd { margin: 0; color: #43555e; font-size: 13px; line-height: 1.65; }

.diagnostic-cards { position: relative; display: grid; gap: 14px; margin: 30px 0 42px; padding-left: 24px; counter-reset: diagnostic; }
.diagnostic-cards::before { position: absolute; inset: 18px auto 18px 7px; width: 3px; background: var(--blue); content: ""; }
.diagnostic-card { position: relative; padding: 18px 20px; background: white; border: 1px solid var(--line); box-shadow: 5px 5px 0 #dfe7e9; counter-increment: diagnostic; }
.diagnostic-card::before { position: absolute; top: 22px; left: -26px; width: 17px; height: 17px; display: grid; place-items: center; color: white; background: var(--blue); border: 3px solid var(--paper); border-radius: 50%; content: counter(diagnostic); font: 8px/1 var(--mono-font); }
.diagnostic-card h4 { margin: 0 0 14px; font: 750 20px/1.25 var(--display-font); }
.diagnostic-card dl { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; margin: 0; background: var(--line); }
.diagnostic-card dl > div { padding: 11px 12px; background: #f4f7f8; }
.diagnostic-card dl > div:nth-child(3), .diagnostic-card dl > div:last-child { grid-column: 1 / -1; }
.diagnostic-card dt { color: var(--blue); font: 700 10px/1.3 var(--mono-font); letter-spacing: .06em; }
.diagnostic-card dd { margin: 5px 0 0; font-size: 12px; line-height: 1.55; }

.advanced-data-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 30px 0 42px; }
.advanced-data-card { padding: 20px; background: white; border-top: 4px solid var(--blue); box-shadow: 0 1px 0 var(--line); }
.advanced-data-card h4 { margin: 0 0 15px; padding-bottom: 12px; border-bottom: 1px solid var(--line); font: 750 19px/1.25 var(--display-font); }
.advanced-data-card dl { display: grid; gap: 12px; margin: 0; }
.advanced-data-card dl > div { display: grid; gap: 4px; }
.advanced-data-card dt { color: var(--blue); font: 700 9px/1.35 var(--mono-font); letter-spacing: .04em; }
.advanced-data-card dd { margin: 0; color: #43555e; font-size: 12px; line-height: 1.5; }

.worksheet-set { display: grid; gap: 18px; margin: 30px 0 46px; }
.worksheet-card { padding: 22px; background: white; border: 1px solid var(--line); border-top: 4px solid var(--blue); }
.worksheet-card h3 { margin: 0 0 17px; font: 750 21px/1.25 var(--display-font); }
.worksheet-card dl { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; margin: 0; background: var(--line); }
.worksheet-card dl > div { min-width: 0; padding: 11px 12px; background: #f4f7f8; }
.worksheet-card dt { color: var(--blue); font: 700 10px/1.35 var(--mono-font); letter-spacing: .04em; }
.worksheet-card dd { margin: 6px 0 0; font-size: 12px; line-height: 1.55; }
.worksheet-card p { margin: 14px 0 0; color: var(--muted); font-size: 11px; }
.worksheet-blank { border-top-color: var(--green); }
.worksheet-blank dt { color: var(--green); }
.write-line { display: block; min-height: 34px; border-bottom: 1px solid #9eb0b8; }

.advanced-bank { margin: 34px 0 64px; border: 1px solid var(--line); background: white; }
.advanced-bank > summary { display: grid; grid-template-columns: 92px 1fr; gap: 2px 14px; padding: 18px 20px; cursor: pointer; list-style: none; background: var(--graphite); color: white; }
.advanced-bank > summary::-webkit-details-marker { display: none; }
.advanced-bank > summary span { grid-row: 1 / 3; color: #7fc1dc; font: 700 11px/1.5 var(--mono-font); letter-spacing: .08em; }
.advanced-bank > summary b { font: 700 18px/1.25 var(--display-font); }
.advanced-bank > summary small { color: #adbec6; font-size: 11px; line-height: 1.45; }
.advanced-bank > div { padding: 8px 24px 28px; }

.soundcheck-timeline { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; padding: 0; background: var(--line); list-style: none; }
.soundcheck-timeline li { display: grid; grid-template-columns: 34px 1fr; gap: 8px; min-height: 112px; margin: 0; padding: 14px; background: white; }
.soundcheck-timeline li > span { color: var(--blue); font: 700 11px/1.4 var(--mono-font); }
.soundcheck-timeline b { display: block; font: 700 15px/1.2 var(--display-font); }
.soundcheck-timeline small { display: block; margin-top: 8px; color: var(--muted); font-size: 10px; line-height: 1.45; }

.mastery-ladder { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; padding: 0; background: var(--line); list-style: none; }
.mastery-ladder li { display: grid; grid-template-columns: 34px 1fr; gap: 8px; min-height: 142px; margin: 0; padding: 16px; background: white; border-top: 4px solid var(--graphite); }
.mastery-ladder li:nth-child(n+4) { border-top-color: var(--blue); }
.mastery-ladder li > span { color: var(--blue); font: 700 10px/1.4 var(--mono-font); }
.mastery-ladder b { font: 750 18px/1.15 var(--display-font); }
.mastery-ladder p { margin: 8px 0 0; color: var(--muted); font-size: 11px; line-height: 1.5; }

.measurement-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.measurement-grid section { padding: 18px; background: #edf3f5; border-top: 4px solid var(--blue); }
.measurement-grid section > span { color: var(--blue); font: 700 10px/1.3 var(--mono-font); letter-spacing: .07em; }
.measurement-grid h3 { min-height: 48px; margin: 10px 0 16px; font: 750 18px/1.25 var(--display-font); }
.measurement-grid p { display: grid; grid-template-columns: 46px 1fr; gap: 8px; margin: 7px 0; color: var(--muted); font-size: 11px; line-height: 1.5; }
.measurement-grid p b { color: var(--ink); }

.state-stack { display: grid; grid-template-columns: repeat(5, 1fr); gap: 7px; align-items: stretch; }
.state-stack section { display: grid; align-content: start; min-width: 0; padding: 14px 12px; background: #edf3f5; border-top: 4px solid var(--blue); }
.state-stack section > span { color: var(--muted); font: 10px/1 var(--mono-font); }
.state-stack section > b { margin-top: 10px; font: 750 15px/1.1 var(--display-font); }
.state-stack section > p { margin: 9px 0 12px; color: #4f626b; font-size: 10px; line-height: 1.45; }
.state-stack section > em { align-self: end; color: var(--green); font: 9px/1.4 var(--mono-font); font-style: normal; }
.recall-band { display: grid; grid-template-columns: 150px 1fr; gap: 16px; margin-top: 10px; padding: 15px; color: white; background: var(--graphite); }
.recall-band b { color: #85c4dc; font: 700 11px/1.4 var(--mono-font); }
.recall-band span { font-size: 12px; line-height: 1.45; }

.operations-loop { display: grid; grid-template-columns: repeat(6, minmax(72px, 1fr) 14px) minmax(72px, 1fr); align-items: stretch; gap: 3px; padding: 0; list-style: none; }
.operations-loop li { display: grid; grid-template-rows: auto 1fr; gap: 9px; min-width: 0; margin: 0; padding: 13px 10px; background: #edf3f5; border-top: 4px solid var(--green); }
.operations-loop li > span { color: var(--green); font: 700 9px/1 var(--mono-font); }
.operations-loop b { display: block; font: 700 12px/1.15 var(--display-font); }
.operations-loop small { display: block; margin-top: 7px; color: var(--muted); font-size: 9px; line-height: 1.4; }
.operations-loop > i { align-self: center; color: var(--blue); font-size: 11px; font-style: normal; text-align: center; }
.operations-return { display: grid; grid-template-columns: auto 1fr auto; gap: 12px; align-items: center; margin-top: 10px; padding: 10px 12px; color: var(--green); background: var(--green-soft); border-top: 2px solid var(--green); font: 700 10px/1.4 var(--mono-font); }
.operations-return i { color: var(--green); font-style: normal; text-align: center; border-top: 1px dashed currentColor; }

.check-box { display: inline-block; width: 1.05em; height: 1.05em; margin-right: .35em; vertical-align: -.1em; border: 1.5px solid var(--muted); }

.broadcast-split { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.broadcast-split section { padding: 18px; background: #f1eef7; border-top: 4px solid var(--violet); }
.broadcast-split section:first-child { background: #e8f0f3; border-top-color: var(--blue); }
.broadcast-split section > span { color: var(--violet); font: 700 10px/1.3 var(--mono-font); letter-spacing: .08em; }
.broadcast-split section:first-child > span { color: var(--blue); }
.broadcast-split section > div { display: flex; align-items: stretch; gap: 6px; margin-top: 13px; }
.broadcast-split section b { flex: 1; display: grid; place-items: center; min-height: 62px; padding: 8px; background: white; border: 1px solid #d4cedf; font-size: 11px; line-height: 1.35; text-align: center; }
.broadcast-split section i { align-self: center; color: var(--violet); font-style: normal; }
.broadcast-split section p { margin: 13px 0 0; color: var(--muted); font-size: 11px; line-height: 1.5; }
.broadcast-chain { display: flex; align-items: stretch; gap: 6px; margin-top: 14px; padding: 12px; background: var(--graphite); }
.broadcast-chain span, .broadcast-chain strong { flex: 1; display: grid; place-items: center; min-width: 0; padding: 9px 6px; color: white; border: 1px solid #52636d; font: 10px/1.35 var(--mono-font); text-align: center; }
.broadcast-chain strong { color: #23193a; background: #cbbce8; border-color: #cbbce8; }
.broadcast-chain i { align-self: center; color: #a99bc8; font-style: normal; }

.listening-lab-diagram ol { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; margin: 0; padding: 0; background: var(--line); list-style: none; }
.listening-lab-diagram li { display: grid; grid-template-columns: 34px 1fr; gap: 8px; min-height: 125px; margin: 0; padding: 16px; background: white; border-top: 4px solid var(--teal); }
.listening-lab-diagram li > span { color: var(--teal); font: 700 10px/1.3 var(--mono-font); }
.listening-lab-diagram b { font: 750 17px/1.2 var(--display-font); }
.listening-lab-diagram small { display: block; margin-top: 8px; color: var(--muted); font-size: 10px; line-height: 1.5; }

.site-workbook-diagram > div { display: flex; align-items: stretch; gap: 5px; }
.site-workbook-diagram section { flex: 1; min-width: 0; display: grid; align-content: start; padding: 14px 10px; background: var(--copper-soft); border-top: 4px solid var(--copper); }
.site-workbook-diagram section > span { color: var(--copper); font: 700 9px/1 var(--mono-font); }
.site-workbook-diagram section > b { margin-top: 9px; font: 750 14px/1.15 var(--display-font); }
.site-workbook-diagram section > small { margin-top: 7px; color: var(--muted); font-size: 9px; line-height: 1.4; }
.site-workbook-diagram section + i { align-self: center; color: var(--copper); font-style: normal; }
.site-workbook-diagram > p { margin: 14px 0 0; padding: 13px 15px; color: #5e4a3d; background: #f7f0ec; font-size: 11px; line-height: 1.55; }
.site-workbook-diagram > p b { color: var(--copper); }

.chapter-pager { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; max-width: var(--content); margin-top: 88px; padding-top: 24px; border-top: 1px solid var(--line); }
.chapter-pager a { padding: 14px; color: var(--graphite); background: #e6edef; text-decoration: none; font-size: 13px; }
.chapter-pager a:last-child { text-align: right; }

.field-library .chapter-header { max-width: var(--content); }
.library-tools { position: sticky; z-index: 5; top: 12px; display: grid; grid-template-columns: auto 1fr auto; gap: 12px; align-items: center; max-width: var(--content); padding: 14px 16px; background: var(--graphite); color: white; }
.library-tools label { font-size: 12px; }
.library-tools input { min-width: 0; padding: 8px 10px; color: white; background: #0e161b; border: 1px solid #4b606b; }
.library-tools output { color: #80c3dd; font: 12px/1 var(--mono-font); }
.field-note-list { max-width: var(--content); margin-top: 28px; border-top: 2px solid var(--graphite); }
.field-record { border-bottom: 1px solid var(--line); }
.field-record[hidden] { display: none; }
.field-record summary { display: grid; grid-template-columns: 82px 1fr 40px; gap: 14px; align-items: start; padding: 18px 8px; cursor: pointer; list-style: none; }
.field-record summary::-webkit-details-marker { display: none; }
.field-record summary span { color: var(--blue); font: 11px/1.6 var(--mono-font); }
.field-record summary b { font-size: 15px; line-height: 1.5; }
.field-record summary em { color: var(--muted); font-size: 11px; font-style: normal; text-align: right; }
.field-record[open] summary { background: var(--blue-soft); }
.field-record > div { padding: 12px 24px 26px 104px; font-size: 14px; }
.field-record > div h4 { margin: 24px 0 8px; }

.context-rail { position: fixed; z-index: 10; inset: 0 0 0 auto; width: var(--context); padding: 30px 22px; overflow-y: auto; background: #e8eef0; border-left: 1px solid var(--line); }
.context-label { margin: 0 0 14px; color: var(--muted); font: 10px/1.4 var(--mono-font); letter-spacing: .08em; }
.context-rule { margin: 28px 0; padding: 14px 0; border-top: 1px solid #bdc9ce; border-bottom: 1px solid #bdc9ce; }
.context-rule b { color: var(--green); font: 700 12px/1.3 var(--mono-font); }
.context-rule p { margin: 6px 0 0; color: var(--muted); font-size: 11px; }
.section-outline { display: grid; }
.section-outline a { padding: 7px 0 7px 12px; color: var(--muted); border-left: 1px solid #bcc9ce; text-decoration: none; font-size: 11px; line-height: 1.4; }
.section-outline a:hover { color: var(--blue); border-left-color: var(--blue); }
.to-top { display: block; margin-top: 24px; color: var(--graphite); font-size: 11px; text-decoration: none; }
.print-button { position: fixed; z-index: 30; right: 18px; bottom: 18px; padding: 8px 11px; color: white; background: var(--graphite); border: 0; box-shadow: 0 3px 10px rgb(0 0 0 / .18); font: 10px/1 var(--mono-font); cursor: pointer; }

@media (max-width: 1280px) {
  :root { --context: 0px; }
  .context-rail { display: none; }
}

@media (max-width: 900px) {
  :root { --sidebar: 0px; }
  html { scroll-padding-top: 58px; }
  body { font-size: 16px; }
  .mobile-bar { position: sticky; z-index: 40; top: 0; display: grid; grid-template-columns: 74px 1fr 74px; align-items: center; height: 52px; color: white; background: var(--graphite); border-bottom: 1px solid #394952; }
  .mobile-bar a { color: white; font: 700 11px/1 var(--mono-font); text-align: center; text-decoration: none; letter-spacing: .06em; }
  .mobile-bar button { height: 100%; color: #cfe0e6; background: transparent; border: 0; font-size: 12px; }
  .sidebar { width: min(88vw, 330px); transform: translateX(-105%); transition: transform .18s ease-out; box-shadow: 14px 0 30px rgb(0 0 0 / .25); }
  .sidebar.is-open { transform: translateX(0); }
  #book { margin: 0; }
  .hero { min-height: auto; max-width: 100%; grid-template-columns: minmax(0, 1fr); padding: 64px clamp(20px, 6vw, 52px); overflow-x: clip; }
  .hero > * { min-width: 0; max-width: 100%; }
  .hero-method { align-self: auto; }
  .flow-chain { width: 100%; max-width: 100%; overflow-x: auto; }
  .flow-step { flex: 0 0 112px; padding: 10px; }
  .flow-step strong { font-size: 15px; overflow-wrap: normal; }
  .flow-arrow { flex-basis: 26px; }
  .course-launch { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .course-launch a { border-bottom: 1px solid var(--line); }
  .course-launch a:nth-child(2n) { border-right: 0; }
  .course-launch a:nth-last-child(-n+2) { border-bottom: 0; }
  .part-launch { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .part-launch a:nth-child(3n) { border-right: 1px solid var(--line); }
  .part-launch a:nth-child(2n) { border-right: 0; }
  .part-launch a:nth-last-child(-n+3) { border-bottom: 1px solid var(--line); }
  .part-launch a:nth-last-child(-n+2) { border-bottom: 0; }
  .part-masthead { padding: 62px clamp(20px, 6vw, 52px) 44px; }
  .level-ladder { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .level-ladder li:nth-child(n+4) { grid-column: span 1; }
  .course-quick-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .wing-procedure-card > summary { grid-template-columns: 52px minmax(0, 1fr) 100px 16px; }
  .wing-procedure-card > summary > small { grid-column: 2 / 4; }
  .evidence-strip { grid-template-columns: 1fr 1fr; }
  .evidence-strip div:nth-child(2) { border-right: 0; }
  .evidence-strip div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .chapter { padding: 74px clamp(20px, 6vw, 52px) 60px; }
  .chapter-header { margin-bottom: 50px; }
  .lesson-console nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .lesson-console nav button { grid-column: 1 / -1; min-height: 92px; }
  .lesson-console nav a::after { display: none; }
  .split-diagram { grid-template-columns: 1fr; }
  .split-diagram figcaption { grid-column: auto; }
  .audio-lanes { grid-template-columns: repeat(3, 1fr); }
  .audio-lanes > i, .audio-lanes > b { grid-column: 1 / -1; }
  .connection-grid > div { align-items: stretch; flex-direction: column; }
  .connection-grid b { flex-basis: auto; }
  .checkpoint-chain { overflow-x: auto; }
  .checkpoint-chain button { flex: 1 0 130px; }
  .soundcheck-timeline { grid-template-columns: 1fr 1fr; }
  .mastery-ladder { grid-template-columns: 1fr 1fr; }
  .state-stack { grid-template-columns: 1fr 1fr; }
  .state-stack section:last-child { grid-column: 1 / -1; }
  .operations-loop { display: flex; overflow-x: auto; padding-bottom: 8px; }
  .operations-loop li { flex: 0 0 128px; }
  .operations-loop > i { flex: 0 0 14px; }
  .operations-return { grid-template-columns: 1fr; }
  .operations-return i { text-align: left; }
  .broadcast-split { grid-template-columns: 1fr; }
  .listening-lab-diagram ol { grid-template-columns: 1fr 1fr; }
  .site-workbook-diagram > div { display: grid; grid-template-columns: 1fr 1fr; }
  .site-workbook-diagram section + i { display: none; }
  .print-button { display: none; }
}

@media (max-width: 600px) {
  .hero h1 { font-size: 46px; }
  .hero-copy > p:last-of-type { font-size: 17px; }
  .hero-actions { align-items: stretch; flex-direction: column; }
  .course-launch { grid-template-columns: minmax(0, 1fr); }
  .course-launch a { grid-column: auto; min-height: 0; border-right: 0; border-bottom: 1px solid var(--line) !important; }
  .course-launch a:last-child { border-bottom: 0 !important; }
  .part-launch { grid-template-columns: 1fr; }
  .part-launch a { min-height: 0; border-right: 0 !important; border-bottom: 1px solid var(--line) !important; }
  .part-launch a:last-child { border-bottom: 0 !important; }
  .part-masthead nav { grid-template-columns: 1fr; }
  .part-masthead nav a { border-right: 0; border-bottom: 1px solid var(--line); }
  .part-masthead nav a:last-child { border-bottom: 0; }
  .curriculum-section-header h2 { font-size: 29px; }
  .level-ladder, .course-quick-nav, .reference-shelf > div { grid-template-columns: 1fr; }
  .course-route > summary { grid-template-columns: 1fr 16px; gap: 7px 12px; padding: 16px; }
  .course-code { grid-column: 1; }
  .course-summary-copy { grid-column: 1; }
  .course-route > summary > em { grid-column: 1; padding-right: 0; }
  .course-route > summary::after { grid-column: 2; grid-row: 1 / 4; align-self: center; }
  .course-route-body { padding: 13px; }
  .course-gate, .module-copy dl, .procedure-body dl { grid-template-columns: 1fr; }
  .course-module { grid-template-columns: 44px minmax(0, 1fr); }
  .module-copy { padding: 14px; }
  .wing-procedure-card > summary { grid-template-columns: 46px minmax(0, 1fr) 16px; gap: 6px 10px; }
  .wing-procedure-card > summary > em, .wing-procedure-card > summary > small { grid-column: 2; }
  .wing-procedure-card > summary::after { grid-column: 3; grid-row: 1 / 4; }
  .procedure-body { padding: 16px; }
  .procedure-body dl > div:nth-last-child(2), .procedure-body .procedure-caveat { grid-column: auto; }
  .signal-rail-compact { grid-template-columns: 1fr; gap: 4px; }
  .signal-rail-compact .rail-node { border-top: 0; border-left: 3px solid #adbbc1; }
  .signal-rail-compact .rail-node.is-active { border-left-color: var(--blue); }
  .chapter-body > h2, .chapter-lesson > h2 { margin-top: 70px; font-size: 29px; }
  .lesson-console { margin-bottom: 42px; }
  .lesson-console nav { grid-template-columns: 1fr; }
  .lesson-console nav a, .lesson-console nav button { min-height: 0; }
  .lesson-console nav button { grid-column: auto; }
  .chapter-body h3 { font-size: 21px; }
  .distance-grid, .two-actions { grid-template-columns: 1fr; }
  .wedge-map { min-height: 380px; }
  .wedge-map .wedge { bottom: 150px; }
  .wedge-map .reject-line { bottom: 187px; }
  .wedge-map p { inset: auto 16px 14px; }
  .feedback-loop { flex-direction: column; }
  .feedback-loop span { width: 100%; }
  .feedback-loop i { transform: rotate(90deg); }
  .feedback-loop .loop-back { transform: none; }
  .path-row { grid-template-columns: 1fr 22px 1fr; }
  .path-row > b { grid-column: 1 / -1; }
  .path-row > span:nth-of-type(3) { grid-column: 1 / -1; }
  .path-row > em { grid-column: 1 / -1; }
  .soundcheck-timeline { grid-template-columns: 1fr; }
  .mastery-ladder, .measurement-grid, .state-stack { grid-template-columns: 1fr; }
  .listening-lab-diagram ol, .site-workbook-diagram > div { grid-template-columns: 1fr; }
  .broadcast-split section > div { flex-direction: column; }
  .broadcast-split section i { transform: rotate(90deg); text-align: center; }
  .broadcast-chain { flex-direction: column; }
  .broadcast-chain i { transform: rotate(90deg); text-align: center; }
  .state-stack section:last-child { grid-column: auto; }
  .recall-band { grid-template-columns: 1fr; }
  .chapter-pager { grid-template-columns: 1fr; }
  .chapter-pager a:last-child { text-align: left; }
  .library-tools { grid-template-columns: 1fr auto; }
  .library-tools label { grid-column: 1 / -1; }
  .field-record summary { grid-template-columns: 76px 1fr; }
  .field-record summary em { display: none; }
  .field-record > div { padding-left: 12px; }
  .reading-stack > header { align-items: flex-start; flex-direction: column; gap: 4px; }
  .reading-card > summary { min-height: 68px; padding: 13px 14px; }
  .reading-card-sequence > summary { grid-template-columns: 34px minmax(0, 1fr) 26px; }
  .reading-card dl > div { grid-template-columns: 1fr; gap: 4px; }
  .reading-summary b { font-size: 17px; }
  .diagnostic-card dl { grid-template-columns: 1fr; }
  .diagnostic-card dl > div { grid-column: auto !important; }
  .worksheet-card dl { grid-template-columns: 1fr; }
  .advanced-data-cards { grid-template-columns: 1fr; }
  .advanced-bank > summary { grid-template-columns: 1fr; }
  .advanced-bank > summary span { grid-row: auto; }
  .advanced-bank > div { padding-inline: 16px; }
}

@media print {
  @page { size: A4; margin: 17mm 16mm 19mm; }
  body { color: #111; background: white; font-size: 10.5pt; }
  .sidebar, .context-rail, .mobile-bar, .print-button, .hero-actions, .chapter-pager, .library-tools, .heading-anchor, .lesson-console { display: none !important; }
  #book { margin: 0; }
  .hero, .chapter { width: auto; max-width: none; padding: 0; border: 0; }
  .hero { min-height: 0; display: block; page-break-after: always; }
  .hero-method, .hero .diagram, .course-launch, .evidence-strip { margin-top: 12mm; box-shadow: none; }
  .chapter { break-before: page; }
  .chapter-header { margin-bottom: 12mm; }
  .chapter-header h1 { font-size: 32pt; }
  .chapter-body { max-width: none; }
  .chapter-body > h2, .chapter-lesson > h2 { margin-top: 14mm; break-after: avoid; }
  .chapter-body.lesson-mode-ready .chapter-lesson { display: block !important; }
  .chapter-body h3, .chapter-body h4 { break-after: avoid; }
  .diagram, .callout, .table-wrap, .field-record, .worksheet-card, .course-module, .wing-procedure-card, .reading-stack { box-shadow: none; break-inside: avoid; }
  .reading-card > .reading-card-body { display: block !important; }
  .table-wrap { overflow: visible; }
  table { min-width: 0; font-size: 8pt; }
  a { color: inherit; text-decoration: none; }
  a[href^="http"]::after { content: ""; }
  .field-record > div { display: block; }
  .advanced-bank > div { display: block; }
  .course-route:not([open]) > :not(summary), .wing-procedure-card:not([open]) > :not(summary) { display: block; }
}