/* Hallmark · pre-emit critique: P4 H5 E4 S5 R4 V5 */
/* Hallmark · genre: editorial · macrostructure: Workbench · theme: Riso · enrichment: F5 real screenshots · nav: N3 · footer: Ft4 · contrast: pass (40–41) · mobile: pass (34, 49–57) */
/* Hallmark · audience: company middle managers without coding background · use: open a lesson and teach · tone: practical editorial */
@import url("tokens.css");

:root {
  --paper: #f2efe7;
  --paper-2: #fbfaf6;
  --ink: #17212b;
  --muted: #62645f;
  --line: #c9c3b7;
  --blue: #214f78;
  --blue-pale: #dfeaf1;
  --red: #ac4c32;
  --red-pale: #f2dfd8;
  --green: #2d6b59;
  --green-pale: #deece7;
  --yellow: #d09c32;
  --shadow: 0 20px 60px rgb(23 33 43 / 12%);
  /* Stable Chinese-first stacks: no remote font request, so the deck looks
     the same in a meeting room, an offline PDF, and on a phone. */
  --sans: "Noto Sans SC", "Source Han Sans SC", "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  --display: "Noto Sans SC", "Source Han Sans SC", "Microsoft YaHei UI", "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", serif;
  --mono: "Cascadia Mono", "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--sans); font-size: 18px; line-height: 1.65; font-synthesis: none; }
button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; }
img { display: block; max-width: 100%; }
[hidden] { display: none !important; }
.skip-link { position: fixed; z-index: 9999; left: 1rem; top: -5rem; background: var(--ink); color: white; padding: .7rem 1rem; }
.skip-link:focus { top: 1rem; }

.site-header { position: sticky; top: 0; z-index: 50; min-height: 76px; display: flex; align-items: center; gap: 2rem; padding: .8rem max(24px, calc((100vw - 1320px) / 2)); background: rgb(242 239 231 / 94%); border-bottom: 1px solid var(--line); backdrop-filter: blur(12px); }
.wordmark { display: flex; align-items: center; gap: .8rem; margin-right: auto; text-decoration: none; line-height: 1.15; }
.wordmark-no { font: 700 13px/1 var(--mono); letter-spacing: .08em; color: var(--red); border-right: 1px solid var(--line); padding-right: .8rem; }
.wordmark strong, .wordmark small { display: block; }
.wordmark strong { font-size: 20px; letter-spacing: .02em; }
.wordmark small { margin-top: .2rem; color: var(--muted); font-size: 13px; }
.top-nav { display: flex; gap: 1.5rem; }
.top-nav a { text-decoration: none; color: #444945; font-size: 15px; }
.top-nav a:hover { color: var(--blue); }
.header-actions { display: flex; gap: .55rem; }
.primary-control, .text-control { border: 1px solid var(--ink); min-height: 44px; padding: .65rem 1rem; cursor: pointer; background: transparent; color: var(--ink); }
.primary-control { color: white; background: var(--ink); }
.primary-control:hover { background: var(--blue); border-color: var(--blue); }
.primary-control.large { min-height: 52px; padding-inline: 1.4rem; font-weight: 700; }

.opening { max-width: 1380px; min-height: calc(100vh - 76px); margin: 0 auto; padding: 7vw 30px 6vw; display: grid; grid-template-columns: .92fr 1.08fr; gap: 5vw; align-items: center; }
.edition, .section-no { font: 700 13px/1.4 var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--red); }
.opening h1 { margin: .8rem 0 1.2rem; font-family: var(--display); font-size: clamp(64px, 7.3vw, 118px); line-height: 1.02; font-weight: 800; letter-spacing: -.055em; }
.opening-thesis { max-width: 660px; margin: 0; font-size: clamp(22px, 1.8vw, 29px); line-height: 1.55; }
.opening-actions { display: flex; align-items: center; gap: 1.3rem; margin: 2rem 0 2.4rem; }
.text-link { text-underline-offset: .28rem; text-decoration-thickness: 1px; }
.opening-facts { margin: 0; display: flex; gap: 2.2rem; }
.opening-facts div { display: flex; align-items: baseline; gap: .5rem; }
.opening-facts dt { font: 700 31px/1 var(--serif); }
.opening-facts dd { margin: 0; color: var(--muted); font-size: 14px; }
.opening-proof { margin: 0; }
.proof-stack { position: relative; min-height: 520px; }
.proof-sheet { position: absolute; border: 1px solid var(--line); background: white; box-shadow: var(--shadow); }
.proof-before { inset: 0 8% 12% 0; transform: rotate(-1.4deg); padding: 10px; }
.proof-before img { width: 100%; height: 100%; object-fit: cover; object-position: center top; filter: saturate(.8); }
.proof-after { right: 0; bottom: 0; width: 56%; padding: 1.5rem 1.7rem; transform: rotate(1.8deg); border-left: 6px solid var(--green); }
.proof-after p { margin: 0 0 .7rem; color: var(--muted); font: 700 13px/1 var(--mono); letter-spacing: .08em; }
.proof-after ol { margin: 0; padding: 0; list-style: none; }
.proof-after li { display: flex; gap: .65rem; align-items: baseline; padding: .35rem 0; border-bottom: 1px solid #ddd8ce; font-size: 16px; }
.proof-after li:last-child { border: 0; }
.proof-after b { min-width: 55px; color: var(--green); font: 700 24px/1 var(--serif); }
.redline { position: absolute; z-index: 2; background: var(--red); color: white; padding: .35rem .55rem; font-size: 14px; font-weight: 700; transform: rotate(-4deg); box-shadow: 0 4px 10px rgb(0 0 0 / 18%); }
.redline-a { left: -1rem; top: 19%; }
.redline-b { right: -1rem; top: 52%; transform: rotate(3deg); }
.opening-proof figcaption { max-width: 650px; margin: 1.5rem auto 0; color: var(--muted); font-size: 15px; }

.audience-band { display: flex; justify-content: space-between; align-items: center; gap: 2rem; padding: 1.5rem max(30px, calc((100vw - 1320px) / 2)); color: white; background: var(--ink); }
.audience-band p { margin: 0; }
.audience-shift { display: flex; align-items: center; gap: 1rem; font-size: 16px; }
.audience-shift i { color: #8fa9bd; font-style: normal; }

.course-section, .evidence-section, .materials-section, .research-section { max-width: 1380px; margin: 0 auto; padding: 7rem 30px; }
.section-intro { max-width: 880px; margin-bottom: 3.2rem; }
.section-intro h2 { margin: .8rem 0 1rem; font-family: var(--display); font-size: clamp(40px, 4.6vw, 70px); line-height: 1.12; font-weight: 800; letter-spacing: -.04em; }
.section-intro > p:last-child { max-width: 760px; margin: 0; font-size: 20px; color: var(--muted); }
.section-intro.inverted h2, .section-intro.inverted > p:last-child { color: white; }

.lesson-list { border-top: 2px solid var(--ink); }
.lesson-row { display: grid; grid-template-columns: 90px minmax(230px, .9fr) 1.2fr 240px 64px; gap: 1.4rem; align-items: center; padding: 1.55rem .2rem; border-bottom: 1px solid var(--line); }
.lesson-row:hover { background: rgb(255 255 255 / 40%); }
.lesson-row > b { color: var(--red); font: 700 26px/1 var(--serif); }
.lesson-row h3 { margin: 0; font-family: var(--display); font-size: 27px; line-height: 1.3; font-weight: 750; }
.lesson-row p { margin: 0; color: var(--muted); }
.lesson-row dl { margin: 0; }
.lesson-row dt { color: var(--muted); font-size: 12px; letter-spacing: .1em; }
.lesson-row dd { margin: .1rem 0 0; font-size: 15px; font-weight: 700; }
.lesson-row button { width: 52px; height: 52px; border: 1px solid var(--ink); border-radius: 50%; background: transparent; cursor: pointer; font-size: 24px; }
.lesson-row button:hover { color: white; background: var(--ink); }

.case-section { padding: 7rem max(30px, calc((100vw - 1320px) / 2)); background: var(--blue); }
.case-timeline { position: relative; display: grid; grid-template-columns: repeat(5, 1fr); gap: 1px; background: rgb(255 255 255 / 28%); }
.case-timeline article { min-height: 330px; padding: 1.6rem; background: var(--blue); color: white; }
.case-timeline article:nth-child(even) { background: #1b4569; }
.case-timeline span { font: 700 48px/1 var(--serif); color: #9fbcd2; }
.case-timeline h3 { margin: 2rem 0 .5rem; font-size: 24px; }
.case-timeline p { font-size: 16px; line-height: 1.65; }
.case-timeline small { display: block; margin-top: 2rem; padding-top: .7rem; border-top: 1px solid rgb(255 255 255 / 28%); color: #d5e2eb; font-size: 13px; }

.evidence-grid { display: grid; gap: 3.5rem; }
.evidence-item { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(300px, .75fr); gap: 3rem; align-items: center; padding-bottom: 3.5rem; border-bottom: 1px solid var(--line); }
.evidence-item:nth-child(even) { grid-template-columns: minmax(300px, .75fr) minmax(0, 1.25fr); }
.evidence-item:nth-child(even) .evidence-visual { order: 2; }
.evidence-item h3 { margin: .4rem 0 .7rem; font-family: var(--display); font-size: 36px; line-height: 1.25; font-weight: 750; }
.evidence-item p { margin: 0; color: var(--red); font: 700 13px/1 var(--mono); letter-spacing: .1em; }
.evidence-item span { color: var(--muted); }
.evidence-visual { min-height: 360px; overflow: hidden; border: 1px solid var(--line); background: white; }
.ocr-strip { padding: 2rem; display: grid; align-content: center; gap: 2rem; background: #e9e5dc; }
.ocr-strip img { width: 100%; min-height: 90px; object-fit: cover; image-rendering: auto; }
.ocr-score { display: flex; gap: 1.2rem; align-items: baseline; }
.ocr-score b { color: var(--red); font: 700 56px/1 var(--serif); }
.ocr-score span { max-width: 260px; font-size: 15px; }
.crop-frame img { width: 100%; height: 420px; object-fit: cover; object-position: top; }
.phone-compare { display: grid; grid-template-columns: 1fr 40px 1fr; gap: 1rem; align-items: center; justify-items: center; padding: 1rem 3rem; background: #e9e5dc; }
.phone-compare img { height: 390px; border: 1px solid #aaa; box-shadow: 0 10px 25px rgb(0 0 0 / 12%); }
.phone-compare i { font-style: normal; font-size: 28px; }

.materials-section { border-top: 1px solid var(--line); }
.material-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; align-items: start; }
.case-folder { position: relative; padding: 2.2rem; background: #e6d6aa; border: 1px solid #bda56d; box-shadow: 7px 9px 0 #d2c08d; }
.folder-tab { position: absolute; left: -1px; top: -38px; min-width: 190px; height: 38px; padding: .45rem 1rem; background: #e6d6aa; border: 1px solid #bda56d; border-bottom: 0; font-size: 13px; font-weight: 700; }
.case-folder h3 { margin: 0 0 .8rem; font-family: var(--display); font-size: 31px; line-height: 1.3; font-weight: 750; }
.case-folder ul { columns: 2; padding: 0; list-style: none; }
.case-folder li { break-inside: avoid; padding: .45rem 0; }
.case-folder a { text-underline-offset: .2rem; }
.template-list { border-top: 2px solid var(--ink); }
.template-list a { display: grid; grid-template-columns: 90px 1fr auto; gap: 1rem; align-items: center; padding: 1rem .2rem; border-bottom: 1px solid var(--line); text-decoration: none; }
.template-list a:hover span { color: var(--blue); }
.template-list b { color: var(--red); font-size: 14px; }
.template-list span { font-size: 20px; font-weight: 700; }
.template-list i { color: var(--muted); font-style: normal; font-size: 13px; }

.research-section { border-top: 1px solid var(--line); }
.research-rule { display: grid; grid-template-columns: 1.1fr .9fr; gap: 4rem; align-items: center; }
.rule-diagram { display: grid; grid-template-columns: 1fr auto 1fr; gap: .7rem; align-items: center; }
.rule-diagram span { min-height: 120px; display: flex; flex-direction: column; justify-content: center; padding: 1rem; border: 1px solid var(--ink); background: var(--paper-2); font-weight: 700; }
.rule-diagram b { color: var(--red); font: 700 24px/1 var(--serif); }
.rule-diagram i { font-style: normal; }
.research-copy p { font-size: 20px; }
.research-copy a { color: var(--blue); text-underline-offset: .2rem; }
.site-footer { display: flex; justify-content: space-between; gap: 2rem; padding: 2.5rem max(30px, calc((100vw - 1320px) / 2)); border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }

/* Presentation shell */
body.deck-open { overflow: hidden; }
.deck-shell { position: fixed; inset: 0; z-index: 1000; display: flex; flex-direction: column; background: #181b1f; color: white; }
.deck-header { flex: 0 0 64px; display: grid; grid-template-columns: 52px minmax(280px, auto) minmax(100px, 1fr) auto; gap: 1.1rem; align-items: center; padding: 0 1rem; background: #f6f3ec; color: var(--ink); border-bottom: 1px solid #aaa; }
.deck-exit { width: 40px; height: 40px; border: 0; background: transparent; cursor: pointer; font-size: 32px; line-height: 1; }
.deck-identity { line-height: 1.15; }
.deck-identity span { display: block; color: var(--red); font-size: 11px; font-weight: 700; letter-spacing: .1em; }
.deck-identity strong { display: block; max-width: 390px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 15px; }
.deck-progress { height: 4px; background: #ddd8ce; }
.deck-progress i { display: block; width: 0; height: 100%; background: var(--red); transition: width .18s ease; }
.deck-tools { display: flex; gap: .35rem; }
.deck-tools button { min-height: 38px; padding: 0 .8rem; border: 1px solid #aaa49a; background: transparent; cursor: pointer; font-size: 13px; }
.deck-tools button:hover, .deck-tools button[aria-pressed="true"] { background: var(--ink); color: white; }
.deck-workspace { min-height: 0; flex: 1; display: grid; grid-template-columns: minmax(0, 1fr); }
.deck-shell.notes-open .deck-workspace { grid-template-columns: minmax(0, 1fr) 420px; }
.projection-wrap { min-width: 0; min-height: 0; position: relative; padding: 18px 18px 58px; display: grid; place-items: center; }
.slide { position: relative; width: min(100%, calc((100vh - 140px) * 16 / 9)); max-height: calc(100vh - 140px); aspect-ratio: 16 / 9; overflow: hidden; background: var(--paper-2); color: var(--ink); box-shadow: 0 12px 40px rgb(0 0 0 / 35%); container-type: inline-size; }
.slide-inner { height: 100%; padding: 4.6cqw 5.6cqw 3.9cqw; display: grid; grid-template-rows: auto 1fr auto; }
.slide-head { display: grid; grid-template-columns: 1fr auto; gap: 2cqw; align-items: start; }
.slide-meta { display: flex; gap: 1.2cqw; align-items: center; color: var(--red); font: 700 1.05cqw/1 var(--mono); letter-spacing: .1em; text-transform: uppercase; }
.slide-head h2 { max-width: 92%; margin: 1cqw 0 .65cqw; font-family: var(--display); font-size: 4cqw; line-height: 1.1; font-weight: 800; letter-spacing: -.045em; }
.slide-lead { max-width: 90%; margin: 0; color: #505652; font-size: 1.6cqw; line-height: 1.42; }
.slide-page { color: #777; font: 700 1.05cqw/1 var(--mono); }
.slide-body { min-height: 0; display: grid; align-content: center; gap: 1.35cqw; margin-top: .9cqw; }
.slide-body.layout-split, .slide-body.layout-compare { grid-template-columns: repeat(2, minmax(0, 1fr)); align-items: stretch; }
.slide-body.layout-three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.slide-body.layout-visual { grid-template-columns: .72fr 1.28fr; align-items: stretch; }
.slide-body.layout-workshop { border: .15cqw solid var(--ink); padding: 1.35cqw; background: #fff; }
.slide-foot { display: flex; justify-content: space-between; align-items: end; gap: 2cqw; padding-top: 1cqw; border-top: .08cqw solid #d2cec5; color: #6d6c67; font-size: .9cqw; line-height: 1.35; }
.slide-foot .source-chip { color: var(--blue); }
.slide-foot strong { color: var(--ink); }

.slide-block { min-width: 0; margin: 0; }
.block-text p, .block-quote p { margin: .4cqw 0 0; font-size: 1.75cqw; line-height: 1.55; }
.block-text h3, .block-points h3, .block-steps h3, .block-checklist h3, .block-image h3 { margin: 0 0 .7cqw; font-size: 1.5cqw; }
.block-quote { position: relative; padding: 2cqw 2.3cqw; background: var(--ink); color: white; }
.block-quote::before { content: "“"; position: absolute; left: .7cqw; top: -.6cqw; color: #8299aa; font: 700 5cqw/1 var(--serif); }
.block-quote p { position: relative; margin: 0; font-family: var(--serif); font-size: 2.25cqw; line-height: 1.45; }
.block-quote small { display: block; margin-top: 1cqw; color: #b9c7d1; font-size: 1cqw; }
.block-points ul, .block-checklist ul { margin: 0; padding: 0; list-style: none; }
.block-points li, .block-checklist li { position: relative; margin: .55cqw 0; padding: .55cqw .5cqw .55cqw 2cqw; border-bottom: .08cqw solid #d5d0c6; font-size: 1.45cqw; line-height: 1.4; }
.block-points li::before { content: attr(data-no); position: absolute; left: 0; color: var(--red); font: 700 1.05cqw/1.7 var(--mono); }
.block-checklist li::before { content: "□"; position: absolute; left: .1cqw; color: var(--blue); font-size: 1.3cqw; }
.block-steps { display: grid; gap: .65cqw; }
.step-row { display: grid; grid-template-columns: 3.2cqw 1fr; gap: 1cqw; align-items: start; padding: .75cqw 0; border-bottom: .08cqw solid #d5d0c6; }
.step-row b { width: 2.6cqw; height: 2.6cqw; display: grid; place-items: center; border-radius: 50%; color: white; background: var(--blue); font: 700 1.1cqw/1 var(--mono); }
.step-row strong { display: block; font-size: 1.45cqw; }
.step-row span { color: #666; font-size: 1.05cqw; }
.block-flow { display: flex; gap: .7cqw; align-items: stretch; justify-content: center; }
.flow-node { position: relative; flex: 1; min-width: 0; padding: 1.2cqw; border: .1cqw solid var(--ink); background: #fff; }
.flow-node b { display: block; color: var(--red); font: 700 1cqw/1 var(--mono); }
.flow-node strong { display: block; margin: .5cqw 0; font-size: 1.5cqw; }
.flow-node span { color: #666; font-size: 1cqw; line-height: 1.4; }
.flow-status { position: absolute; right: .65cqw; top: .55cqw; padding: .24cqw .42cqw; color: #555 !important; background: #e7e3da; font: 700 max(.72cqw, 11px)/1 var(--mono); letter-spacing: .04em; }
.flow-node[data-status] strong { padding-right: 5.4cqw; }
.flow-node[data-status="candidate"], .flow-node[data-status="verify"] { border-color: var(--blue); background: var(--blue-pale); }
.flow-node[data-status="live"], .flow-node[data-status="rollback"] { border-color: var(--green); background: var(--green-pale); }
.flow-node[data-status="fail"] { border-color: var(--red); background: var(--red-pale); }
.flow-node[data-status="learn"], .flow-node[data-status="standby"] { border-color: #8b877f; background: #eeeae1; }
.flow-node[data-status="candidate"] .flow-status, .flow-node[data-status="verify"] .flow-status { color: white !important; background: var(--blue); }
.flow-node[data-status="live"] .flow-status, .flow-node[data-status="rollback"] .flow-status { color: white !important; background: var(--green); }
.flow-node[data-status="fail"] .flow-status { color: white !important; background: var(--red); }
.flow-arrow { align-self: center; font-size: 1.5cqw; }
.block-flow.flow-vertical,
.slide-body.layout-visual > .block-flow.flow-many,
.slide-body.layout-split > .block-flow.flow-many { flex-direction: column; gap: .3cqw; }
.block-flow.flow-vertical .flow-node,
.slide-body.layout-visual > .block-flow.flow-many .flow-node,
.slide-body.layout-split > .block-flow.flow-many .flow-node { padding: .5cqw .75cqw; }
.block-flow.flow-vertical .flow-node strong,
.slide-body.layout-visual > .block-flow.flow-many .flow-node strong,
.slide-body.layout-split > .block-flow.flow-many .flow-node strong { display: inline; margin-right: .5cqw; font-size: 1.15cqw; }
.block-flow.flow-vertical .flow-node span,
.slide-body.layout-visual > .block-flow.flow-many .flow-node span,
.slide-body.layout-split > .block-flow.flow-many .flow-node span { display: inline; font-size: .88cqw; }
.block-flow.flow-vertical .flow-arrow,
.slide-body.layout-visual > .block-flow.flow-many .flow-arrow,
.slide-body.layout-split > .block-flow.flow-many .flow-arrow { line-height: .5; transform: rotate(90deg); }
.block-compare { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1.2cqw; height: 100%; }
.compare-col { padding: 1.5cqw; border-top: .35cqw solid var(--red); background: #eeeae1; }
.compare-col.after, .compare-col.good { border-color: var(--green); background: var(--green-pale); }
.compare-col h3 { margin: 0 0 .8cqw; font-size: 1.4cqw; }
.compare-col p { margin: 0; font-size: max(1.32cqw, 18px); line-height: 1.5; white-space: pre-wrap; }
.block-stats { display: grid; grid-template-columns: repeat(var(--count, 3), 1fr); gap: 1cqw; }
.stat-item { padding: 1.4cqw; border-left: .25cqw solid var(--blue); background: var(--blue-pale); }
.stat-item b { display: block; font: 700 3cqw/1 var(--serif); color: var(--blue); }
.stat-item span { display: block; margin-top: .6cqw; font-size: 1.1cqw; line-height: 1.35; }
.stat-item small { display: block; margin-top: .35cqw; color: #52636f; font-size: max(.88cqw, 13px); line-height: 1.35; }
.block-table { overflow: hidden; border: .08cqw solid #a9a49a; background: white; }
.block-table table { width: 100%; border-collapse: collapse; font-size: max(1.08cqw, 16px); line-height: 1.38; }
.block-table th, .block-table td { padding: .55cqw .65cqw; border-right: .06cqw solid #d2cec5; border-bottom: .06cqw solid #d2cec5; text-align: left; vertical-align: top; }
.block-table th { color: white; background: var(--blue); }
.block-table tr.highlight td { background: var(--red-pale); color: #7b2716; font-weight: 700; }
.table-note { display: block; padding: .5cqw .65cqw; color: #565a57; background: #eeeae1; font-size: max(.9cqw, 14px); line-height: 1.4; }
.block-prompt, .block-result { padding: 1.4cqw; border-left: .3cqw solid var(--blue); background: #e7edf1; font-family: var(--mono); font-size: 1.08cqw; line-height: 1.55; white-space: pre-wrap; }
.block-result { border-color: var(--green); background: var(--green-pale); font-family: var(--sans); }
.block-prompt .label, .block-result .label { display: block; margin-bottom: .6cqw; color: var(--blue); font: 700 .9cqw/1 var(--mono); letter-spacing: .08em; }
.copy-block { float: right; margin-top: .7cqw; padding: .35cqw .65cqw; border: .08cqw solid currentColor; color: var(--blue); background: transparent; cursor: pointer; font-family: var(--sans); font-size: .78cqw; }
.block-image { position: relative; min-height: 0; height: 100%; overflow: hidden; background: #e5e1d8; border: .08cqw solid #aaa49a; }
.block-image img { width: 100%; height: 100%; object-fit: contain; }
.block-image.cover img { object-fit: cover; }
.block-image.crop-top img { object-fit: cover; object-position: top; }
.image-caption { position: absolute; left: 0; right: 0; bottom: 0; padding: .58cqw .8cqw; color: white; background: rgb(23 33 43 / 86%); font-size: max(.96cqw, 14px); line-height: 1.35; }
.annotation { position: absolute; max-width: 30%; padding: .38cqw .55cqw; color: white; background: var(--red); font-size: max(.96cqw, 14px); line-height: 1.25; font-weight: 700; box-shadow: .2cqw .2cqw 0 rgb(0 0 0 / 15%); }
.annotation[data-auto-position="true"]:nth-of-type(even) { background: var(--blue); }
.block-folder { padding: 1.2cqw; border: .08cqw solid #a99b7e; background: #e9d9ad; }
.folder-head { display: flex; justify-content: space-between; padding-bottom: .65cqw; border-bottom: .08cqw solid #b9a57d; font-weight: 700; font-size: 1.15cqw; }
.file-row { display: grid; grid-template-columns: 2.2cqw 1fr auto; align-items: center; gap: .6cqw; padding: .34cqw 0; border-bottom: .06cqw solid rgb(90 75 42 / 18%); font-size: 1cqw; }
.file-row i { width: 1.65cqw; height: 2cqw; display: grid; place-items: center; background: white; border: .06cqw solid #a99b7e; font: 700 .7cqw/1 var(--mono); }
.file-row em { color: #7a6b4b; font-style: normal; }
.block-decision-shell { position: relative; }
.block-decision { display: grid; grid-template-columns: repeat(var(--decision-cols, 3), minmax(0, 1fr)); gap: 1cqw; }
.decision-question { margin: 0 0 1cqw; font-family: var(--serif); font-size: 1.8cqw; font-weight: 700; }
.decision-card { padding: 1.3cqw; border: .12cqw solid var(--ink); background: white; text-align: center; }
.decision-card b { display: block; margin-bottom: .5cqw; font: 700 1.8cqw/1 var(--serif); }
.decision-card span { color: #666; font-size: 1cqw; line-height: 1.4; }
.decision-card.recommended { color: white; background: var(--blue); border-color: var(--blue); }
.decision-card.recommended span { color: #dce7ef; }
.decision-reveal-toggle { margin-top: .7cqw; min-height: 2.25cqw; padding: .35cqw .7cqw; border: .08cqw solid var(--blue); color: var(--blue); background: white; cursor: pointer; font-size: max(.82cqw, 13px); font-weight: 700; }
.decision-reveal { display: flex; gap: .8cqw; align-items: baseline; margin-top: .55cqw; padding: .65cqw .8cqw; border-left: .28cqw solid var(--green); background: var(--green-pale); font-size: max(.98cqw, 15px); line-height: 1.4; }
.decision-reveal b { color: var(--green); white-space: nowrap; }
.decision-revealed .decision-card[data-correct="true"] { color: white; border-color: var(--green); background: var(--green); }
.decision-revealed .decision-card[data-correct="true"] span { color: white; }
.block-formula { display: flex; justify-content: center; align-items: center; gap: 1.3cqw; padding: 1.5cqw; background: #e9e5dc; }
.formula-part { text-align: center; }
.formula-part b { display: block; font: 700 2.7cqw/1 var(--serif); }
.formula-part span { color: #666; font-size: .95cqw; }
.formula-op { color: var(--red); font: 700 2.2cqw/1 var(--serif); }
.block-callout { --callout-accent: var(--yellow); --callout-bg: #f3e7c8; padding: 1.4cqw 1.7cqw; border: .1cqw solid var(--callout-accent); border-left-width: .38cqw; background: var(--callout-bg); }
.block-callout b { color: var(--callout-accent); font: 700 1cqw/1 var(--mono); letter-spacing: .08em; }
.block-callout p { margin: .6cqw 0 0; font-family: var(--display); font-size: 1.8cqw; line-height: 1.42; font-weight: 650; }
.block-callout[data-tone="instruction"], .block-callout[data-tone="question"], .block-callout[data-tone="verify"], .block-callout[data-tone="blue"], .block-callout[data-tone="next"] { --callout-accent: var(--blue); --callout-bg: var(--blue-pale); }
.block-callout[data-tone="efficiency"], .block-callout[data-tone="evidence"], .block-callout[data-tone="answer"], .block-callout[data-tone="green"] { --callout-accent: var(--green); --callout-bg: var(--green-pale); }
.block-callout[data-tone="warning"], .block-callout[data-tone="red"] { --callout-accent: var(--red); --callout-bg: var(--red-pale); }
.block-callout[data-tone="synthetic"] { --callout-accent: #625e57; --callout-bg: #e8e4dc; }
.slide-body.layout-three > .block-callout:last-child { grid-column: 1 / -1; }
.block-timer { display: grid; place-items: center; padding: 1.6cqw; color: white; background: var(--red); }
.block-timer b { font: 700 5cqw/1 var(--mono); }
.block-timer span { font-size: 1.2cqw; }
.slide-body.layout-workshop .block-quote { padding: 1.1cqw 1.5cqw; }
.slide-body.layout-workshop .block-quote p { font-size: 1.75cqw; }
.slide-body.layout-workshop .step-row { padding: .35cqw 0; }
.slide-body.layout-workshop .file-row { padding: .25cqw 0; }
.slide-body.layout-workshop .block-callout { padding: .7cqw 1.1cqw; }
.slide-body.layout-workshop .block-callout p { font-size: 1.35cqw; }
.slide-body.layout-workshop .block-checklist li { margin: .22cqw 0; padding-top: .3cqw; padding-bottom: .3cqw; font-size: 1.2cqw; }

.slide.type-exercise .slide-inner { background: #f5e8c9; }
.slide.type-answer .slide-inner { background: var(--green-pale); }
.slide.type-evidence .slide-inner { background: #edf1f3; }
.slide.type-recap .slide-inner { color: white; background: var(--blue); }
.slide.type-recap .slide-meta, .slide.type-recap .slide-foot, .slide.type-recap .slide-lead { color: #d6e2eb; }
.slide.type-recap .slide-foot { border-color: rgb(255 255 255 / 30%); }
.slide.type-recap .slide-foot strong { color: white; }
.slide.type-recap .slide-head h2 { font-size: 3.75cqw; }
.slide.type-recap .slide-body { gap: .85cqw; margin-top: .7cqw; }
.slide.type-recap .flow-node,
.slide.type-recap .block-table,
.slide.type-recap .block-formula,
.slide.type-recap .block-folder,
.slide.type-recap .block-prompt,
.slide.type-recap .block-result,
.slide.type-recap .block-callout,
.slide.type-recap .decision-card,
.slide.type-recap .compare-col,
.slide.type-recap .stat-item { color: var(--ink); }
.slide.type-recap .flow-node { padding: .75cqw; }
.slide.type-recap .flow-node strong { margin: .3cqw 0; font-size: 1.2cqw; }
.slide.type-recap .flow-node span { font-size: .85cqw; }
.slide.type-recap .block-points li,
.slide.type-recap .block-checklist li { margin: .25cqw 0; padding-top: .35cqw; padding-bottom: .35cqw; font-size: 1.2cqw; }
.slide.type-recap .step-row { padding: .4cqw 0; }
.slide.type-recap .step-row strong { font-size: 1.25cqw; }
.slide.type-recap .step-row span { font-size: .9cqw; }
.slide.type-recap .block-callout { padding: .8cqw 1.2cqw; }
.slide.type-recap .block-callout p { font-size: 1.35cqw; }
.slide.type-recap .block-formula { padding: .8cqw; }
.slide.type-recap .formula-part b { font-size: 1.85cqw; }

/* Content-responsive slide layouts. These are driven by teaching structure,
   so the same rules protect projection, presenter view and print. */
.slide-body > .block-flow.flow-many:only-child {
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: .9cqw;
  align-content: center;
}
.slide-body > .block-flow.flow-many:only-child .flow-node {
  min-height: 7.2cqw;
  padding: 1.05cqw 1.15cqw;
}
.slide-body > .block-flow.flow-many:only-child .flow-node strong {
  display: block;
  margin: .45cqw 0;
  font-size: 1.28cqw;
}
.slide-body > .block-flow.flow-many:only-child .flow-node span {
  display: block;
  font-size: .9cqw;
}
.slide-body > .block-flow.flow-many:only-child .flow-arrow { display: none; }

.slide-body.layout-full:has(> .block-folder + .block-folder) {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: .9cqw 1.25cqw;
  align-content: center;
  align-items: start;
}
.slide-body.layout-full:has(> .block-folder + .block-folder) > .block-checklist,
.slide-body.layout-full:has(> .block-folder + .block-folder) > .block-points,
.slide-body.layout-full:has(> .block-folder + .block-folder) > .block-callout {
  grid-column: 1 / -1;
}

.slide.type-recap .slide-body.layout-full:has(> .block-points + .block-checklist) {
  grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
  gap: 2.2cqw;
  align-content: center;
  align-items: start;
}
.slide.type-recap .slide-body.layout-full:has(> .block-points + .block-checklist) > .block-checklist {
  padding-left: 1.6cqw;
  border-left: .08cqw solid rgb(255 255 255 / 34%);
}

.slide-controls { position: absolute; left: 50%; bottom: 8px; transform: translateX(-50%); display: flex; align-items: center; gap: 1rem; }
.slide-controls button { width: 42px; height: 38px; border: 1px solid #666; color: white; background: transparent; cursor: pointer; }
.slide-controls button:disabled { opacity: .25; }
.slide-controls div { min-width: 118px; text-align: center; line-height: 1.15; }
.slide-controls strong, .slide-controls span { display: block; }
.slide-controls strong { font: 700 13px/1 var(--mono); }
.slide-controls span { margin-top: .2rem; color: #aaa; font-size: 11px; }
.presenter-panel { display: none; min-width: 0; color: var(--ink); background: #eeeae1; border-left: 1px solid #777; }
.deck-shell.notes-open .presenter-panel { display: flex; flex-direction: column; }
.presenter-panel > header { flex: 0 0 64px; display: flex; align-items: center; justify-content: space-between; padding: .7rem 1rem; border-bottom: 1px solid var(--line); background: #f8f6f0; }
.presenter-panel > header span, .presenter-panel > header strong { display: block; }
.presenter-panel > header span { color: var(--muted); font-size: 11px; }
.presenter-panel > header strong { font-size: 15px; }
.presenter-panel > header button { border: 0; background: transparent; cursor: pointer; color: var(--blue); font: 700 13px/1 var(--mono); }
.presenter-scroll { overflow: auto; padding: 1rem 1.2rem 3rem; }
.presenter-scroll section { padding: .8rem 0 1rem; border-bottom: 1px solid var(--line); }
.presenter-scroll h3 { margin: 0 0 .4rem; color: var(--muted); font: 700 11px/1 var(--mono); letter-spacing: .1em; }
.presenter-scroll p { margin: .3rem 0; font-size: 15px; line-height: 1.55; }
.presenter-scroll small { display: block; padding: .55rem .65rem; background: #ddd8ce; font-size: 13px; line-height: 1.45; }
.say-this { border-left: 4px solid var(--red); padding-left: .8rem !important; }
.say-this p { font-family: var(--serif); font-size: 18px; font-weight: 700; }
.presenter-scroll a { color: var(--blue); font-size: 13px; }
.blackout { position: absolute; inset: 64px 0 0; z-index: 20; display: grid; place-items: center; background: black; }
.blackout p { color: #777; font-size: 18px; }

.index-dialog { width: min(1100px, 94vw); height: min(820px, 90vh); padding: 0; color: var(--ink); background: var(--paper-2); border: 1px solid var(--ink); }
.index-dialog::backdrop { background: rgb(0 0 0 / 68%); }
.dialog-head { display: flex; justify-content: space-between; align-items: center; padding: 1.1rem 1.4rem; border-bottom: 1px solid var(--line); }
.dialog-head span { color: var(--red); font: 700 11px/1 var(--mono); letter-spacing: .1em; }
.dialog-head h2 { margin: .25rem 0 0; font-family: var(--display); font-size: 30px; font-weight: 750; }
.dialog-head button { width: 44px; height: 44px; border: 0; background: transparent; font-size: 30px; cursor: pointer; }
.index-body { height: calc(100% - 88px); overflow: auto; padding: 1rem 1.4rem 2rem; }
.index-lesson { display: grid; grid-template-columns: 230px 1fr; gap: 1.2rem; padding: 1.2rem 0; border-bottom: 1px solid var(--line); }
.index-lesson h3 { margin: 0; font-family: var(--display); font-size: 23px; font-weight: 750; }
.index-lesson p { margin: .4rem 0; color: var(--muted); font-size: 13px; }
.index-slides { display: grid; grid-template-columns: repeat(4, 1fr); gap: .5rem; }
.index-slides button { min-height: 60px; padding: .6rem; border: 1px solid var(--line); background: transparent; text-align: left; cursor: pointer; font-size: 12px; line-height: 1.35; }
.index-slides button:hover { color: white; background: var(--blue); border-color: var(--blue); }
.index-slides b { display: block; margin-bottom: .2rem; color: var(--red); font: 700 10px/1 var(--mono); }
.toast { position: fixed; z-index: 2000; left: 50%; bottom: 1rem; transform: translate(-50%, 120%); padding: .7rem 1rem; color: white; background: var(--ink); opacity: 0; transition: .2s ease; font-size: 14px; }
.toast.show { transform: translate(-50%, 0); opacity: 1; }
.print-root { display: none; }

@media (max-width: 1100px) {
  .top-nav { display: none; }
  .opening { grid-template-columns: 1fr; padding-top: 4rem; }
  .opening h1 { font-size: clamp(62px, 13vw, 108px); }
  .proof-stack { min-height: 470px; }
  .lesson-row { grid-template-columns: 60px 1fr 1fr 52px; }
  .lesson-row dl { display: none; }
  .case-timeline { grid-template-columns: 1fr 1fr; }
  .case-timeline article:last-child { grid-column: 1 / -1; min-height: 240px; }
  .research-rule { grid-template-columns: 1fr; }
  .deck-shell.notes-open .deck-workspace { grid-template-columns: 1fr 350px; }
}

@media (max-width: 720px) {
  body { font-size: 16px; }
  .site-header { min-height: 64px; padding: .6rem 16px; }
  .wordmark-no, .wordmark small, .text-control { display: none; }
  .wordmark strong { font-size: 18px; }
  .primary-control { min-height: 42px; padding: .55rem .75rem; font-size: 14px; }
  .opening { min-height: auto; padding: 4rem 20px 4rem; gap: 3rem; }
  .opening h1 { font-size: clamp(56px, 18vw, 86px); }
  .opening-thesis { font-size: 20px; }
  .opening-actions { align-items: flex-start; flex-direction: column; }
  .opening-facts { gap: 1.1rem; }
  .opening-facts div { display: block; }
  .proof-stack { min-height: 330px; }
  .proof-before { inset: 0 3% 15% 0; }
  .proof-after { width: 72%; padding: 1rem; }
  .proof-after li { font-size: 12px; }
  .proof-after b { min-width: 38px; font-size: 18px; }
  .redline { font-size: 11px; }
  .audience-band { align-items: flex-start; flex-direction: column; padding: 1.3rem 20px; }
  .audience-shift { align-items: flex-start; flex-direction: column; gap: .3rem; }
  .audience-shift i { transform: rotate(90deg); }
  .course-section, .evidence-section, .materials-section, .research-section { padding: 5rem 20px; }
  .section-intro { margin-bottom: 2rem; }
  .section-intro h2 { font-size: 42px; }
  .section-intro > p:last-child { font-size: 17px; }
  .lesson-row { grid-template-columns: 44px 1fr 48px; gap: .7rem; padding: 1.1rem 0; }
  .lesson-row > p { grid-column: 2; font-size: 14px; }
  .lesson-row h3 { font-size: 21px; }
  .lesson-row button { grid-column: 3; grid-row: 1 / 3; width: 44px; height: 44px; }
  .case-section { padding: 5rem 20px; }
  .case-timeline { grid-template-columns: 1fr; }
  .case-timeline article, .case-timeline article:last-child { grid-column: auto; min-height: 250px; }
  .evidence-item, .evidence-item:nth-child(even) { grid-template-columns: 1fr; gap: 1.4rem; }
  .evidence-item:nth-child(even) .evidence-visual { order: 0; }
  .evidence-visual { min-height: 280px; }
  .crop-frame img { height: 320px; }
  .phone-compare { padding: 1rem; }
  .phone-compare img { height: 270px; }
  .material-layout { grid-template-columns: 1fr; gap: 3.5rem; }
  .case-folder { padding: 1.4rem; }
  .case-folder ul { columns: 1; }
  .template-list a { grid-template-columns: 72px 1fr; }
  .template-list i { grid-column: 2; }
  .rule-diagram { grid-template-columns: 1fr; }
  .rule-diagram i { transform: rotate(90deg); justify-self: center; }
  .site-footer { flex-direction: column; padding: 2rem 20px; }
  .deck-header { grid-template-columns: 40px 1fr auto; gap: .4rem; padding: 0 .4rem; }
  .deck-progress { display: none; }
  .deck-tools button:not(#toggleNotes) { display: none; }
  .deck-identity strong { max-width: 170px; font-size: 12px; }
  .projection-wrap { padding: 8px 4px 56px; }
  .slide { width: 100%; }
  .deck-shell.notes-open .deck-workspace { grid-template-columns: 1fr; grid-template-rows: auto minmax(0, 1fr); overflow: auto; }
  .deck-shell.notes-open .projection-wrap { min-height: 250px; }
  .deck-shell.notes-open .presenter-panel { min-height: 50vh; border-left: 0; border-top: 1px solid #777; }
  .index-lesson { grid-template-columns: 1fr; }
  .index-slides { grid-template-columns: repeat(2, 1fr); }
  /* Phone deck is a scaled overview; projector px floors would otherwise
     overpower the 16:9 canvas at this width. */
  .slide .block-table table { font-size: 1.02cqw; }
  .slide .table-note { font-size: .78cqw; }
  .slide .image-caption { font-size: .85cqw; }
  .slide .stat-item small { font-size: .78cqw; }
  .slide .annotation { font-size: .9cqw; }
  .slide .compare-col p { font-size: 1.25cqw; }
  .slide .flow-status { font-size: .72cqw; }
  .slide .decision-reveal-toggle { font-size: .82cqw; }
  .slide .decision-reveal { font-size: .98cqw; }
}

@media print {
  @page { size: 13.333in 7.5in; margin: 0; }
  body > *:not(.print-root) { display: none !important; }
  .print-root { display: block !important; }
  .print-slide { width: 13.333in; height: 7.5in; break-after: page; overflow: hidden; }
  .print-slide .slide { width: 100%; height: 100%; max-height: none; box-shadow: none; }
  .print-slide .slide-inner { print-color-adjust: exact; -webkit-print-color-adjust: exact; }
  .print-slide .decision-reveal-toggle { display: none; }
  .print-slide .decision-reveal[hidden] { display: flex !important; }
  .print-slide .block-decision-shell[data-answer] .decision-card[data-correct="true"] { color: white; border-color: var(--green); background: var(--green); }
  .print-slide .block-decision-shell[data-answer] .decision-card[data-correct="true"] span { color: white; }
}

@media (prefers-reduced-motion: reduce) { * { scroll-behavior: auto !important; transition: none !important; } }

/* Hallmark redesign layer — additive by contract; the original deck engine remains intact. */
:root {
  --paper: var(--color-paper);
  --paper-2: var(--color-paper-2);
  --ink: var(--color-ink);
  --muted: var(--color-muted);
  --line: var(--color-rule);
  --blue: var(--color-accent);
  --blue-pale: var(--color-paper-2);
  --red: var(--color-error);
  --red-pale: var(--color-paper-2);
  --green: var(--color-success);
  --green-pale: var(--color-paper-2);
  --yellow: var(--color-accent-2);
  --shadow: none;
  --sans: var(--font-body);
  --display: var(--font-display);
  --serif: var(--font-body);
  --mono: var(--font-outlier);
}

html,
body {
  overflow-x: clip;
}

h1,
h2,
h3 {
  min-width: 0;
  overflow-wrap: anywhere;
  font-style: normal;
}

html {
  scroll-padding-top: var(--space-4xl);
}

body {
  min-width: 20rem;
  padding-block-end: 4.75rem;
  color: var(--color-ink);
  background: var(--color-paper);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.65;
}

button,
a {
  white-space: nowrap;
}

:focus-visible {
  outline: var(--rule-strong) solid var(--color-focus);
  outline-offset: var(--space-2xs);
}

.skip-link {
  z-index: var(--z-tooltip);
  color: var(--color-accent-ink);
  background: var(--color-ink);
}

.hallmark-rail {
  position: sticky;
  z-index: var(--z-sticky);
  inset-block-start: 0;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: var(--space-sm);
  min-height: 4rem;
  padding: var(--space-xs) var(--space-md);
  border-block-end: var(--rule-hairline) solid var(--color-rule-2);
  color: var(--color-ink);
  background: var(--color-paper);
}

.rail-wordmark {
  display: flex;
  align-items: baseline;
  gap: var(--space-xs);
  min-height: 2.75rem;
  text-decoration: none;
}

.rail-wordmark strong {
  font-family: var(--font-outlier);
  font-size: var(--text-xl);
  line-height: 1;
}

.rail-wordmark span {
  font-weight: 700;
}

.rail-nav {
  display: none;
}

.rail-actions {
  display: flex;
  gap: var(--space-xs);
}

.primary-control,
.text-control,
.lesson-row button,
.deck-tools button,
.deck-exit,
.slide-controls button,
.copy-block,
.decision-reveal-toggle {
  min-width: 2.75rem;
  min-height: 2.75rem;
  border-width: var(--rule-hairline);
  border-style: solid;
  border-color: var(--color-ink);
  border-radius: var(--radius-card);
  color: var(--color-ink);
  background: var(--color-paper);
  font-family: var(--font-body);
  font-weight: 700;
  transition: background-color var(--dur-short) var(--ease-out), color var(--dur-short) var(--ease-out), transform var(--dur-micro) var(--ease-out);
}

.primary-control {
  color: var(--color-accent-ink);
  background: var(--color-ink);
}

.primary-control:focus-visible {
  outline-color: var(--color-accent-2);
  box-shadow: 0 0 0 var(--space-2xs) var(--color-ink);
}

.primary-control.large {
  min-height: 3.25rem;
  padding-inline: var(--space-lg);
  font-size: var(--text-base);
}

@media (hover: hover) and (pointer: fine) {
  .primary-control:hover,
  .text-control:hover,
  .lesson-row button:hover,
  .deck-tools button:hover,
  .deck-exit:hover,
  .slide-controls button:hover,
  .copy-block:hover,
  .decision-reveal-toggle:hover {
    color: var(--color-accent-ink);
    background: var(--color-accent);
    transform: translateY(-1px);
  }
}

.primary-control:active,
.text-control:active,
.lesson-row button:active,
.deck-tools button:active,
.deck-exit:active,
.slide-controls button:active,
.copy-block:active,
.decision-reveal-toggle:active {
  transform: translateY(1px);
}

button:disabled,
button[aria-disabled="true"] {
  opacity: 0.5;
  cursor: not-allowed;
}

button[data-state="loading"]::after {
  content: " · 处理中";
}

button[data-state="error"] {
  border-color: var(--color-error);
}

button[data-state="success"]::after {
  content: " · 已完成";
}

.hallmark-main {
  min-width: 0;
}

.workbench-opening {
  max-width: 94rem;
  margin-inline: auto;
  padding: var(--space-xl) var(--space-md) var(--space-3xl);
}

.opening-ledger {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs) var(--space-lg);
  padding-block: var(--space-sm);
  border-block: var(--rule-hairline) solid var(--color-rule-2);
  font-family: var(--font-outlier);
  font-size: var(--text-sm);
  font-variant-numeric: tabular-nums;
}

.workbench-intro {
  display: grid;
  gap: var(--space-xl);
  padding-block: var(--space-2xl);
}

.workbench-note {
  max-width: 36ch;
  margin: 0 0 var(--space-sm);
  color: var(--color-neutral);
  font-size: var(--text-sm);
}

.workbench-intro h1 {
  min-width: 0;
  max-width: 8ch;
  margin: 0;
  overflow-wrap: anywhere;
  font-family: var(--font-display);
  font-size: var(--text-display);
  font-style: normal;
  font-weight: 800;
  line-height: 0.98;
  letter-spacing: -0.045em;
}

.intro-brief {
  align-self: end;
  display: grid;
  justify-items: start;
  gap: var(--space-lg);
}

.intro-brief p {
  max-width: 48ch;
  margin: 0;
  font-size: var(--text-lg);
  line-height: 1.55;
}

.live-workbench {
  position: relative;
  margin: 0;
  padding: var(--space-xs);
  border: var(--rule-strong) solid var(--color-ink);
  background: var(--color-paper-2);
}

.live-workbench img {
  width: 100%;
  height: auto;
  border: var(--rule-hairline) solid var(--color-rule);
}

.live-workbench figcaption {
  display: grid;
  gap: var(--space-xs);
  padding: var(--space-md) var(--space-xs) var(--space-xs);
  color: var(--color-neutral);
  font-size: var(--text-sm);
}

.live-workbench figcaption span {
  display: flex;
  gap: var(--space-xs);
}

.live-workbench figcaption b {
  color: var(--color-accent);
  font-family: var(--font-body);
}

.audience-band {
  display: grid;
  gap: var(--space-md);
  padding: var(--space-lg) var(--space-md);
  border-block: var(--rule-strong) solid var(--color-ink);
  color: var(--color-ink);
  background: var(--color-paper-3);
}

.audience-band p,
.audience-band strong {
  margin: 0;
}

.audience-band strong {
  font-size: var(--text-lg);
}

.course-section,
.evidence-section,
.materials-section,
.research-section {
  max-width: 94rem;
  margin-inline: auto;
  padding: var(--space-3xl) var(--space-md);
}

.section-intro {
  display: grid;
  gap: var(--space-md);
  max-width: 78rem;
  margin: 0 0 var(--space-2xl);
}

.section-intro h2 {
  min-width: 0;
  max-width: 18ch;
  margin: 0;
  overflow-wrap: anywhere;
  font-family: var(--font-display);
  font-size: var(--text-display-s);
  font-style: normal;
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.section-intro > p:last-child {
  max-width: 56ch;
  margin: 0;
  color: var(--color-neutral);
  font-size: var(--text-md);
}

.lesson-list {
  border-block-start: var(--rule-strong) solid var(--color-ink);
}

.lesson-row {
  display: grid;
  grid-template-columns: 3rem minmax(0, 1fr) 3rem;
  gap: var(--space-sm);
  align-items: center;
  padding: var(--space-lg) 0;
  border-block-end: var(--rule-hairline) solid var(--color-rule-2);
  background: transparent;
}

.lesson-row > b {
  color: var(--color-accent);
  font-family: var(--font-body);
  font-size: var(--text-lg);
  font-variant-numeric: tabular-nums;
}

.lesson-row h3 {
  min-width: 0;
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 800;
  line-height: 1.35;
}

.lesson-row > p {
  grid-column: 2;
  margin: 0;
  color: var(--color-neutral);
  font-size: var(--text-base);
}

.lesson-row dl {
  display: none;
}

.lesson-row button {
  grid-column: 3;
  grid-row: 1 / 3;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border-radius: var(--radius-card);
  cursor: pointer;
}

.case-section {
  padding: var(--space-3xl) var(--space-md) var(--space-4xl);
  color: var(--color-paper);
  background: var(--color-ink);
}

.case-section .section-intro {
  max-width: 94rem;
  margin-inline: auto;
}

.case-section .section-intro h2,
.case-section .section-intro p {
  color: var(--color-paper);
}

.case-timeline {
  display: grid;
  max-width: 94rem;
  margin-inline: auto;
  border-block-start: var(--rule-hairline) solid var(--color-rule-2);
}

.case-timeline article,
.case-timeline article:last-child {
  display: grid;
  grid-template-columns: 4rem minmax(0, 1fr);
  gap: var(--space-xs) var(--space-md);
  min-height: 0;
  padding: var(--space-xl) 0;
  border-block-end: var(--rule-hairline) solid var(--color-rule-2);
  background: transparent;
}

.case-timeline article:nth-child(even) {
  background: transparent;
}

.case-timeline article > span {
  grid-row: 1 / 4;
  color: var(--color-accent-2);
  font-family: var(--font-body);
  font-size: var(--text-lg);
  font-variant-numeric: tabular-nums;
}

.case-timeline h3,
.case-timeline p,
.case-timeline small {
  margin: 0;
}

.case-timeline h3 {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 800;
}

.case-timeline p {
  max-width: 52ch;
  color: var(--color-paper-2);
}

.case-timeline small {
  color: var(--color-accent-2);
  font-size: var(--text-sm);
}

.evidence-grid {
  display: grid;
  gap: var(--space-3xl);
}

.evidence-item,
.evidence-item:nth-child(even) {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-lg);
  align-items: center;
  padding-block: 0 var(--space-3xl);
  border-block-end: var(--rule-hairline) solid var(--color-rule-2);
}

.evidence-item > div {
  display: grid;
  gap: var(--space-sm);
}

.evidence-item h3,
.evidence-item p {
  margin: 0;
}

.evidence-item h3 {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 800;
  line-height: 1.2;
}

.evidence-item p {
  max-width: 48ch;
  color: var(--color-neutral);
}

.evidence-visual {
  position: relative;
  min-width: 0;
  min-height: 0;
  margin: 0;
  padding: var(--space-md);
  border: var(--rule-hairline) solid var(--color-rule-2);
  background: var(--color-paper-2);
}

.evidence-visual img {
  width: 100%;
  height: auto;
  object-fit: contain;
}

.evidence-visual figcaption {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  padding-block-start: var(--space-md);
  color: var(--color-neutral);
  font-size: var(--text-sm);
}

.evidence-visual figcaption b {
  color: var(--color-accent);
}

.phone-compare {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  gap: var(--space-sm);
  align-items: center;
}

.phone-compare img {
  width: 100%;
  height: min(60svh, 36rem);
  object-fit: contain;
}

.phone-compare figcaption {
  grid-column: 1 / -1;
}

.materials-section {
  padding-block-start: var(--space-4xl);
}

.material-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-3xl);
}

.case-folder {
  position: relative;
  padding: var(--space-xl);
  border: var(--rule-strong) solid var(--color-ink);
  border-radius: var(--radius-card);
  background: var(--color-paper-2);
  box-shadow: none;
}

.case-folder::after {
  display: none;
}

.folder-tab {
  position: static;
  display: inline-block;
  margin-block-end: var(--space-lg);
  padding: var(--space-xs) var(--space-sm);
  border: var(--rule-hairline) solid var(--color-ink);
  background: var(--color-accent-2);
}

.case-folder h3 {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 800;
}

.case-folder ul {
  columns: 1;
  gap: var(--space-xl);
}

.case-folder a,
.template-list a,
.research-copy a {
  text-decoration-thickness: var(--rule-hairline);
  text-underline-offset: var(--space-2xs);
}

.template-list {
  border-block-start: var(--rule-strong) solid var(--color-ink);
}

.template-list a {
  display: grid;
  grid-template-columns: 5rem minmax(0, 1fr);
  gap: var(--space-xs) var(--space-md);
  align-items: baseline;
  min-height: 4.75rem;
  padding: var(--space-md) 0;
  border-block-end: var(--rule-hairline) solid var(--color-rule-2);
  text-decoration: none;
}

.template-list b {
  color: var(--color-accent);
}

.template-list span {
  font-size: var(--text-md);
  font-weight: 700;
}

.template-list i {
  grid-column: 2;
  color: var(--color-neutral);
  font-style: normal;
  font-size: var(--text-sm);
}

.research-section {
  padding-block-end: var(--space-4xl);
}

.research-rule {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-2xl);
}

.rule-diagram {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-sm);
}

.rule-diagram span {
  min-height: 0;
  padding: var(--space-lg);
  border: var(--rule-hairline) solid var(--color-ink);
  background: transparent;
}

.rule-diagram i {
  justify-self: start;
  transform: rotate(90deg);
  font-style: normal;
}

.research-copy p {
  max-width: 62ch;
  font-size: var(--text-md);
}

.research-copy li {
  margin-block: var(--space-xs);
}

.site-footer {
  display: block;
  margin-inline: 0;
  padding: var(--space-2xl) var(--space-md) calc(var(--space-2xl) + 4.75rem);
  border-block-start: var(--rule-strong) solid var(--color-ink);
  color: var(--color-paper);
  background: var(--color-ink);
}

.site-footer p {
  max-width: 75ch;
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--text-sm);
  line-height: 1.75;
}

.hallmark-sticky {
  position: fixed;
  z-index: var(--z-sticky);
  inset-inline: 0;
  inset-block-end: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-md);
  min-height: 4.75rem;
  padding: var(--space-xs) var(--space-md);
  border-block-start: var(--rule-strong) solid var(--color-ink);
  color: var(--color-ink);
  background: var(--color-paper);
}

.hallmark-sticky span {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.deck-shell {
  background: var(--color-ink);
}

.deck-header,
.presenter-panel,
.slide-controls,
.index-dialog,
.dialog-head {
  color: var(--color-ink);
  background: var(--color-paper);
}

.slide {
  border-radius: var(--radius-card);
  background: var(--color-paper-2);
  box-shadow: none;
}

.deck-progress i {
  background: var(--color-accent);
}

.presenter-panel {
  border-color: var(--color-rule-2);
}

.presenter-scroll section,
.dialog-head,
.index-lesson,
.index-slides button {
  border-color: var(--color-rule);
}

.toast {
  z-index: var(--z-toast);
  border-radius: var(--radius-card);
  color: var(--color-accent-ink);
  background: var(--color-ink);
}

@media (min-width: 40rem) {
  body {
    font-size: var(--text-md);
  }

  .workbench-opening,
  .course-section,
  .evidence-section,
  .materials-section,
  .research-section {
    padding-inline: var(--space-xl);
  }

  .audience-band {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr);
    align-items: center;
    padding-inline: var(--space-xl);
  }

  .lesson-row {
    grid-template-columns: 4rem minmax(14rem, 0.85fr) minmax(16rem, 1.15fr) 3rem;
    gap: var(--space-lg);
  }

  .lesson-row > p {
    grid-column: auto;
  }

  .lesson-row button {
    grid-column: 4;
    grid-row: 1;
  }

  .case-timeline article,
  .case-timeline article:last-child {
    grid-template-columns: 5rem minmax(12rem, 0.6fr) minmax(18rem, 1fr) minmax(12rem, 0.65fr);
    align-items: baseline;
  }

  .case-timeline article > span {
    grid-row: auto;
  }

  .evidence-visual figcaption {
    font-size: var(--text-base);
  }

  .case-folder ul {
    columns: 2;
  }

  .template-list a {
    grid-template-columns: 6rem minmax(0, 1fr) auto;
  }

  .template-list i {
    grid-column: auto;
  }
}

@media (min-width: 60rem) {
  html {
    scroll-padding-top: var(--space-xl);
  }

  .hallmark-rail {
    position: fixed;
    inset-block: 0;
    inset-inline-start: 0;
    width: 5.5rem;
    min-height: 100svh;
    grid-template-columns: 1fr;
    grid-template-rows: auto minmax(0, 1fr) auto;
    justify-items: center;
    padding: var(--space-lg) var(--space-sm) calc(var(--space-lg) + 4.75rem);
    border-block-end: 0;
    border-inline-end: var(--rule-strong) solid var(--color-ink);
  }

  .rail-wordmark {
    flex-direction: column;
    align-items: center;
    gap: var(--space-2xs);
  }

  .rail-wordmark strong {
    font-size: var(--text-2xl);
  }

  .rail-wordmark span {
    writing-mode: vertical-rl;
    font-size: var(--text-sm);
    letter-spacing: 0.08em;
  }

  .rail-nav {
    align-self: center;
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
  }

  .rail-nav a {
    position: relative;
    display: grid;
    justify-items: center;
    gap: var(--space-2xs);
    min-width: 2.75rem;
    min-height: 2.75rem;
    color: var(--color-neutral);
    text-decoration: none;
  }

  .rail-nav b {
    font-family: var(--font-body);
    font-size: var(--text-sm);
    font-variant-numeric: tabular-nums;
  }

  .rail-nav span {
    position: absolute;
    inset-inline-start: calc(100% + var(--space-sm));
    inset-block-start: 50%;
    padding: var(--space-xs) var(--space-sm);
    border: var(--rule-hairline) solid var(--color-ink);
    color: var(--color-accent-ink);
    background: var(--color-ink);
    opacity: 0;
    pointer-events: none;
    transform: translate(-0.5rem, -50%);
    transition: opacity var(--dur-short) var(--ease-out), transform var(--dur-short) var(--ease-out);
  }

  .rail-nav a:hover span,
  .rail-nav a:focus-visible span {
    opacity: 1;
    transform: translate(0, -50%);
  }

  .rail-actions {
    flex-direction: column;
  }

  .hallmark-main,
  .site-footer {
    margin-inline-start: 5.5rem;
  }

  .hallmark-sticky {
    inset-inline-start: 5.5rem;
    padding-inline: var(--space-xl);
  }

  .workbench-opening {
    padding-block-start: var(--space-2xl);
  }

  .workbench-intro {
    grid-template-columns: minmax(0, 1.25fr) minmax(18rem, 0.75fr);
    gap: var(--space-3xl);
    align-items: end;
  }

  .live-workbench {
    padding: var(--space-md);
  }

  .live-workbench figcaption {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--space-lg);
  }

  .audience-band {
    margin-inline-start: 5.5rem;
    padding-inline: max(var(--space-xl), calc((100% - 94rem) / 2));
  }

  .evidence-item,
  .evidence-item:nth-child(even) {
    grid-template-columns: minmax(0, 1.35fr) minmax(18rem, 0.65fr);
    gap: var(--space-2xl);
  }

  .evidence-item:nth-child(even) {
    grid-template-columns: minmax(18rem, 0.65fr) minmax(0, 1.35fr);
  }

  .evidence-item:nth-child(even) .evidence-visual {
    order: 2;
  }

  .material-layout {
    grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
    gap: var(--space-3xl);
  }

  .research-rule {
    grid-template-columns: minmax(0, 0.9fr) minmax(24rem, 1.1fr);
    gap: var(--space-3xl);
  }

  .site-footer {
    padding-inline: var(--space-xl);
  }
}

@media (min-width: 90rem) {
  .workbench-opening,
  .course-section,
  .evidence-section,
  .materials-section,
  .research-section {
    padding-inline: var(--space-2xl);
  }

  .evidence-grid {
    gap: var(--space-4xl);
  }
}

@media (pointer: coarse) {
  button,
  .rail-nav a,
  .template-list a {
    min-height: 3rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 150ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 150ms !important;
  }

  .rail-nav span {
    transform: translate(0, -50%);
  }
}