/* Reading hierarchy: resource → learning outcome → decision → evidence. */
:root {
  --paper: light-dark(#F7F6F2, #171b1c);
  --line: light-dark(#e4e7e2, #354143);
  --sub: light-dark(#596966, #acbbb7);
}
body { font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif; font-size: 16px; line-height: 1.75; }
.shell { grid-template-columns: 208px minmax(0, 1fr); }
.side { padding: 32px 16px; background: var(--paper); }
.side-inner { top: 32px; max-height: calc(100vh - 64px); }
.brand { margin: 0 8px 34px; gap: 10px; }
.brandwords strong { font-size: 22px; }
.brandwords small { font-size: 12px; margin-top: 3px; }
.brandmark { width: 34px; height: 36px; flex-basis: 34px; }
.nav a { min-height: 44px; padding: 10px 13px; font-size: 15px; border-radius: 9px; color: var(--sub); }
.nav a.active { background: var(--soft); }
.navlabel { font-size: 13px; letter-spacing: 0; padding: 26px 13px 8px; }
.sidebottom { margin-top: 28px; padding-top: 18px; }
.github { font-size: 14px; border: 0; justify-content: flex-start; padding: 9px 13px; }
.appearance { border-radius: 10px; max-width: 160px; margin: 16px auto 0; }
.appearance button { min-width: 40px; min-height: 36px; justify-content: center; border-radius: 7px; }
.content { max-width: 1232px; margin: 0 auto; padding: 44px 48px 28px; }
h1 { font-size: 34px; line-height: 1.3; letter-spacing: -1px; font-weight: 650; }
.head { align-items: center; margin-bottom: 26px; }
.lead { font-size: 16px; line-height: 1.75; margin-top: 10px; }
.head-link { display: inline-flex; align-items: center; gap: 8px; font-size: 14px; white-space: nowrap; }
.eyebrow { font-size: 12px; margin-bottom: 10px; }
.pill { font-size: 13px; }
.search { min-height: 58px; padding: 10px 16px; border-radius: 12px; }
.search input { font-size: 16px; outline-offset: 4px; }
.search button[type=submit] { background: var(--brand); color: var(--on); font-size: 14px; padding: 8px 15px; border-radius: 8px; }
.quick { margin: 10px 0 24px; gap: 18px; }
.quick a { display: inline-flex; align-items: center; gap: 4px; padding: 5px 0; font-size: 13px; color: var(--sub); }
.quick a:hover { color: var(--brand); }
.quick .icon { width: 13px; height: 13px; }
.filters { align-items: center; padding-bottom: 16px; gap: 12px; }
.filters .row { gap: 6px; }
.chip { font-size: 14px; padding: 7px 12px; border-radius: 8px; }
.filters a.chip { border-color: transparent; background: transparent; color: var(--sub); }
.filters a.chip.active { background: var(--soft); color: var(--brand); font-weight: 600; }
select { font-size: 13px; padding: 8px 9px; border-radius: 8px; }
.sort, .sort a, .muted { font-size: 13px; }
.sort a { padding: 8px 2px; }
.sort { gap: 20px; }
.datehead { margin: 32px 0 16px; gap: 14px; }
.datehead h2 { font-size: 22px; }
.datehead span { font-size: 13px; }
.timeline { grid-template-columns: 48px minmax(0, 1fr); gap: 16px; margin-bottom: 16px; }
.time { padding-top: 23px; font-size: 12px; font-weight: 400; }
.time:after { top: 29px; background: var(--line); }
.time:before { top: 39px; }
.resource { padding: 20px 24px; border-radius: 12px; transition: border-color .15s; }
.resource:hover { border-color: color-mix(in srgb, var(--brand) 35%, var(--line)); }
.resmeta { font-size: 13px; margin-bottom: 8px; gap: 12px; flex-wrap: nowrap; }
.origin { min-width: 0; }
.resource .resbody, .catalog .resbody, .tree-results .resbody { display: grid; grid-template-columns: minmax(0, 1fr) 76px; align-items: center; gap: 24px; }
.rescopy { min-width: 0; }
.resource .title, .catalog .title { font-size: 20px; font-weight: 650; line-height: 1.5; margin-bottom: 8px; letter-spacing: -.25px; }
.resource .outcome { font-size: 15px; line-height: 1.8; color: var(--sub); }
.resource .cover-compact, .catalog .cover-compact, .tree-results .cover-compact { width: 76px; height: 94px; padding: 0; margin: 0; display: grid; place-items: center; justify-content: center; align-content: center; border-radius: 8px; }
.cover-compact .icon { width: 28px; height: 28px; opacity: .85; }
.cover-compact strong, .cover-compact small, .cover-compact em { display: none; }
/* No official image: institution + course code, typeset instead of a generic icon. */
.cover-compact.cover-mark { display: flex !important; flex-direction: column; align-items: center; justify-content: center; gap: 3px; padding: 4px; text-align: center; }
.cover-compact.cover-mark:before { opacity: .5; }
.cover-compact.cover-mark small { display: block; font-size: 9px; letter-spacing: .3px; opacity: .75; z-index: 1; }
.cover-compact.cover-mark b { display: block; font: 700 15px/1.15 Georgia, 'Times New Roman', serif; letter-spacing: -.3px; white-space: nowrap; z-index: 1; max-width: 100%; }
.cover-compact.cover-mark.mark-m b { font-size: 12px; letter-spacing: -.4px; }
.cover-compact.cover-mark.mark-l b { font-size: 10.5px; letter-spacing: -.5px; }
.cover-compact.cover-mark.mark-w b { font-size: 11px; line-height: 1.2; white-space: normal; overflow-wrap: anywhere; }
.detailhero > .cover-compact.cover-mark b { font-size: 21px; }
.detailhero > .cover-compact.cover-mark.mark-m b { font-size: 17px; }
.detailhero > .cover-compact.cover-mark.mark-l b { font-size: 15px; }
.detailhero > .cover-compact.cover-mark.mark-w b { font-size: 15px; }
.detailhero > .cover-compact.cover-mark small { font-size: 11px; }
.cover-compact:before { width: 120px; height: 120px; right: -60px; top: -10px; }
.cover-compact.grid:before, .cover-compact.neural:before { width: 120px; height: 120px; right: -40px; }
.cardfacts { display: flex; align-items: center; flex-wrap: wrap; gap: 8px 12px; margin-top: 12px; }
.resource-form { font-size: 13px; color: var(--sub); }
.cardfacts .badges { margin: 0; gap: 8px; }
.badge { font-size: 12px; padding: 3px 7px; border-radius: 5px; }
.cardfacts .badge.free { padding: 0; background: none; }
.resourcefoot { margin-top: 17px; padding-top: 12px; gap: 10px 18px; }
.resourcefoot .topiccrumb { margin: 0; gap: 8px; }
.topiccrumb, .topiccrumb a { font-size: 13px; }
.resourcefoot > .row { gap: 14px; margin-left: auto; }
.iconbtn { font-size: 13px; min-width: 32px; min-height: 32px; padding: 6px; gap: 5px; border-radius: 6px; }
.iconbtn:hover { background: var(--soft); color: var(--brand); }
.link { font-size: 14px; padding: 6px 0; }
.catalog { align-items: start; gap: 18px; margin-top: 24px; }
.catalog .resource { height: 100%; display: flex; flex-direction: column; }
.catalog .resourcefoot { margin-top: auto; padding-top: 14px; }
.catalog .resbody { margin-bottom: 18px; }
.catalog .title { font-size: 19px; }
.catalog .resbody { grid-template-columns: minmax(0,1fr) 58px; gap: 16px; }
.catalog .cover-compact { width: 58px; height: 78px; }
.catalog .cover-mark.mark-s b { font-size: 13px; }
.catalog .cover-mark.mark-m b { font-size: 10px; }
.catalog .cover-mark.mark-w b { font-size: 10px; }
.catalog .cover-mark.mark-l b { font-size: 9px; }
.primary, .secondary { font-size: 14px; padding: 10px 15px; border-radius: 8px; }
.section { margin: 30px 0; }
.section h2 { font-size: 22px; margin-bottom: 16px; }
.section h3 { font-size: 17px; }
.section p, .section li, .box p { font-size: 15px; line-height: 1.9; }
.notice { font-size: 14px; line-height: 1.85; padding: 15px 18px; }
.box { padding: 22px; border-radius: 12px; }
.box h3 { font-size: 16px; }
.detailhero { grid-template-columns: minmax(0,1fr) 124px; gap: 32px; margin: 24px 0 30px; }
.detailhero h1 { font-size: 32px; line-height: 1.45; }
.detailhero .outcome { font-size: 17px; line-height: 1.8; margin: 16px 0 24px; }
.detailhero > .cover { width: 124px; height: 156px; }
.detailhero > .cover strong { font-size: 21px; max-width: 100%; overflow: hidden; }
.detailhero > .cover small, .detailhero > .cover em { font-size: 10px; }
.tabs { gap: 24px; margin-bottom: 28px; }
.tabs a { font-size: 15px; padding: 12px 0; }
.detailgrid { grid-template-columns: minmax(0,1fr) 256px; gap: 32px; }
.detailgrid .section:first-child { margin-top: 0; }
.detailrail .box { padding: 20px; }
.detailrail summary { font-size: 14px; cursor: pointer; color: var(--sub); margin-top: 14px; }
.props dt { font-size: 13px; }
.props dd { font-size: 14px; line-height: 1.8; }
.check { font-size: 15px; padding: 14px 0; }
.step h3 { font-size: 17px; }
.step p, pre { font-size: 14px; }
.tree-layout { grid-template-columns: 240px minmax(0,1fr); gap: 28px; margin-top: 30px; }
.tree { border: 0; background: transparent; padding: 0 16px 0 0; border-right: 1px solid var(--line); border-radius: 0; }
.tree-title { font-size: 14px; margin-bottom: 10px; }
.tree-pick { font-size: 14px; padding: 8px 5px; }
.tree-pick small { font-size: 12px; }
.roots a { padding: 20px; }
.roots small { font-size: 14px; line-height: 1.8; margin-top: 8px; }
.empty { font-size: 15px; padding: 40px 20px; }
.footer { display: flex; justify-content: space-between; align-items: center; gap: 20px; padding-top: 24px; margin-top: 48px; font-size: 13px; flex-wrap: wrap; }
.footer nav { gap: 20px; }
.footer a { text-decoration: none; }
.footer a:hover { text-decoration: underline; }
@media (max-width: 1200px) {
  .content { padding: 36px 32px 24px; }
  .catalog { grid-template-columns: 1fr; }
  .catalog .resbody { grid-template-columns: minmax(0,1fr) 76px; }
  .catalog .cover-compact { width: 76px; height: 94px; }
  .catalog .cover-mark.mark-s b { font-size: 15px; }
  .catalog .cover-mark.mark-m b { font-size: 12px; }
  .catalog .cover-mark.mark-w b { font-size: 11px; }
  .catalog .cover-mark.mark-l b { font-size: 10.5px; }
  .detailgrid { grid-template-columns: minmax(0,1fr) 220px; gap: 24px; }
}
@media (max-width: 960px) {
  .shell { display: block; }
  .side { position: relative; padding: 18px 24px 12px; border-right: 0; border-bottom: 1px solid var(--line); }
  .side-inner { position: static; max-height: none; overflow: visible; }
  .brand { margin: 0 90px 20px 0; }
  .brandwords strong { font-size: 21px; }
  .brandwords small { font-size: 12px; }
  .mobile-menu { display: block; position: absolute; top: 24px; right: 24px; font-size: 14px; padding: 8px; color: var(--sub); }
  .side-inner > .nav { display: grid; grid-template-columns: repeat(4,minmax(0,1fr)); gap: 4px; }
  .side-inner > .nav a { justify-content: center; padding: 8px 4px; font-size: 14px; gap: 7px; }
  .side-extra { display: none; }
  body[data-menu="open"] .side-extra { display: block; }
  .side-extra .nav { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); }
  .sidebottom { display: flex; justify-content: space-between; align-items: center; margin-top: 16px; }
  .github { width: auto; }
  .appearance { margin: 0; }
  .content { padding: 30px 28px 24px; }
  .tree-layout { grid-template-columns: 200px minmax(0,1fr); gap: 24px; }
  .detailgrid { grid-template-columns: 1fr; }
  .detailrail { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
}
@media (max-width: 610px) {
  .side { padding: 16px 14px 10px; }
  .brand { margin-bottom: 16px; }
  .mobile-menu { right: 14px; top: 19px; }
  .content { padding: 26px 16px 20px; }
  h1 { font-size: 28px; }
  .head { gap: 12px; margin-bottom: 20px; }
  .head-link { font-size: 13px; }
  .lead { font-size: 15px; margin-top: 8px; }
  .search { padding: 8px 10px; min-height: 54px; gap: 8px; }
  .search input { font-size: 16px; }
  .search button[type=submit] { padding: 8px 10px; }
  .quick { gap: 20px; margin-bottom: 18px; }
  .filters { gap: 12px; }
  .filters > .row { gap: 2px; }
  .chip { font-size: 13px; padding: 7px 8px; }
  .filters form { width: 100%; }
  .filters select { flex: 1; font-size: 13px; }
  .datehead { margin: 24px 0 10px; }
  .datehead h2 { font-size: 20px; }
  .timeline { display: block; margin-bottom: 0; }
  .time { padding: 18px 4px 0; font-size: 12px; }
  .time:before, .time:after { display: none; }
  .resource { padding: 16px 4px 20px; background: transparent; border: 0; border-bottom: 1px solid var(--line); border-radius: 0; }
  .timeline .resource { padding-top: 5px; }
  .resmeta { font-size: 13px; margin-bottom: 8px; }
  .resource .resbody, .catalog .resbody, .tree-results .resbody { grid-template-columns: minmax(0,1fr); gap: 0; }
  .resource .cover-compact { display: none; }
  .resource .title, .catalog .title { font-size: 19px; line-height: 1.55; }
  .resource .outcome { font-size: 15px; line-height: 1.85; }
  .cardfacts { margin-top: 10px; }
  .resourcefoot { padding: 10px 0 0; margin-top: 12px; border: 0; gap: 10px; }
  .resourcefoot .row { gap: 10px; }
  .resourcefoot .topiccrumb, .resourcefoot .topiccrumb a { font-size: 12px; }
  .catalog { gap: 0; margin-top: 12px; }
  .catalog .resbody { margin-bottom: 0; }
  .catalog .resourcefoot { margin-top: 12px; }
  .detailhero { display: block; margin-top: 20px; }
  .detailhero h1 { font-size: 27px; }
  .detailhero .outcome { font-size: 16px; }
  .detailhero > .cover { display: none; }
  .detailhero .row { gap: 10px; }
  .tabs { gap: 8px 18px; }
  .tabs a { font-size: 14px; padding: 10px 0; }
  .twobox, .detailrail { grid-template-columns: 1fr; }
  .tree-layout { grid-template-columns: 1fr; gap: 28px; }
  .tree { padding: 16px; border: 1px solid var(--line); border-radius: 12px; }
  .tree-results .resource { margin-top: 0; }
  .box { padding: 18px; }
  .footer { font-size: 12px; margin-top: 32px; gap: 14px; }
  .footer nav { gap: 16px; }
}

.detailhero > .cover-compact { display: grid; place-items: center; justify-content: center; align-content: center; padding: 0; }
.detailhero > .cover-compact .icon { width: 42px; height: 42px; }
.sourcecard p, .sourcecard li { font-size: 15px; line-height: 1.85; }
.sourcecard h3 { font-size: 20px; }
.sourcecard li { margin: 10px 0; }
.sourcecard li .muted { display: block; }

@media (max-width: 610px) { .detailhero > .cover-compact { display: none; } }
.learning-main { min-width: 0; }
.learning-main > .section { scroll-margin-top: 28px; padding-top: 32px; border-top: 1px solid var(--line); margin-top: 36px; }
.learning-main > .section:first-child { margin-top: 0; }
.course-version { font-size: 14px; color: var(--sub); margin: 10px 0; line-height: 1.7; }
.learning-fit { margin: 0; display: grid; gap: 16px; }
.learning-fit > div { display: grid; grid-template-columns: 82px minmax(0, 1fr); gap: 16px; }
.learning-fit dt { color: var(--sub); font-size: 14px; }
.learning-fit dd { margin: 0; font-size: 15px; line-height: 1.85; }
.guide-more { margin: 18px 0; }
.guide-more summary { cursor: pointer; font-size: 15px; color: var(--brand); padding: 10px 0; }
.course-cost { margin-top: 20px; font-size: 14px !important; color: var(--sub); }
.choice-rows { display: grid; gap: 12px; margin: 22px 0 6px; }
.choice-rows > div { display: grid; grid-template-columns: 82px minmax(0, 1fr); gap: 16px; align-items: center; }
.choice-label { color: var(--sub); font-size: 14px; }
.choice-rows .route-options, .choice-rows .guide-systems { margin: 0; }
.tools-heading { font-size: 16px; margin: 28px 0 4px; }
.section .tool-list { list-style: none; padding: 0; margin: 0; }
.tool-list li { display: grid; grid-template-columns: 180px minmax(0, 1fr); gap: 16px; padding: 12px 0; border-bottom: 1px solid var(--line); font-size: 15px; line-height: 1.75; }
.tool-name { font-weight: 600; display: flex; gap: 8px; align-items: baseline; flex-wrap: wrap; }
.tool-name .muted { font-weight: 400; font-size: 12px; }
.tool-name .link { font-size: inherit; }
.setup-steps { padding-left: 22px; margin: 4px 0 0; }
.setup-steps h4 { font-size: 15px; margin: 0 0 6px; }
.guide-lead { margin: 12px 0 16px; line-height: 1.85; }
.guide-lead .link { white-space: nowrap; margin-left: 4px; }
.source-facts { margin: 16px 0 0; display: grid; gap: 0; }
.source-facts > div { display: grid; grid-template-columns: 82px minmax(0, 1fr); gap: 16px; padding: 10px 0; border-bottom: 1px solid var(--line); }
.source-facts dt { color: var(--sub); font-size: 13px; line-height: 1.85; }
.source-facts dd { margin: 0; font-size: 14px; line-height: 1.85; }
.source-links { display: flex; flex-wrap: wrap; gap: 4px 18px; }
.workspace-tree { white-space: pre-wrap; background: var(--soft); border: 1px solid var(--line); padding: 20px; border-radius: 10px; margin-top: 18px; line-height: 1.9; color: var(--ink); }
.route-options { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0; }
.route-intro { margin-top: 18px; }
.guide-verification { font-size: 13px !important; color: var(--sub); padding-bottom: 18px; }
.step-context { color: var(--sub); font-size: 13px !important; margin-top: 12px; }
.cover.has-image { background: #fff; border: 1px solid var(--line); }
.cover.has-image:before, .cover.has-image:after { display: none; }
.cover.has-image img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: contain; padding: 6px; z-index: 2; background: #fff; }
.learning-tabs { flex-wrap: nowrap; gap: 30px; scroll-margin-top: 24px; }
.learning-tabs a { white-space: nowrap; }
.learning-panel { max-width: 960px; }
.learning-panel > .section { border-top: 0; margin-top: 0; padding-top: 4px; }
#course-setup-prompt, #course-lesson-prompt { max-height: 380px; overflow-y: auto; font-family: inherit; font-size: 14px; line-height: 1.9; padding: 22px; }
.study-instructions { margin-top: 32px; }
.study-instructions ol { padding-left: 24px; }
.study-instructions li { padding-left: 4px; margin: 12px 0; }
.setup-reference { padding: 16px 0; border-bottom: 1px solid var(--line); }
.source-notes { border-top: 1px solid var(--line); padding-top: 28px; margin-top: 40px; }
.source-notes h2 { font-size: 18px; }
.source-declarations { margin-top: 18px; color: var(--sub); }
.source-declarations p { font-size: 12px; line-height: 1.8; margin: 6px 0; }
@media (max-width: 610px) { .learning-tabs { gap: 18px; justify-content: space-between; } .learning-tabs a { font-size: 14px; } #course-setup-prompt, #course-lesson-prompt { font-size: 13px; padding: 16px; max-height: 340px; } }
@media (max-width: 610px) { .learning-fit > div, .choice-rows > div, .tool-list li, .source-facts > div { grid-template-columns: 1fr; gap: 4px; } }
/* 学前准备 / 学习指南: two tabs for every resource. */
.learning-panel h2.prep-tools { margin-top: 44px; }
.learning-fit dd .muted { font-size: 14px; }
.next-step { display: inline-block; margin-top: 28px; font-size: 15px; font-weight: 600; color: var(--brand); }
.next-step:hover { text-decoration: underline; }
#guide > .guide-more { margin-top: 14px; }
.study-instructions h3 { font-size: 16px; margin: 28px 0 8px; }
.syllabus-list { padding-left: 24px; columns: 2; column-gap: 40px; }
.syllabus-list li { break-inside: avoid; margin: 0 0 10px; font-size: 15px; }
@media (max-width: 610px) { .syllabus-list { columns: 1; } }
.related-notes { border-top: 1px solid var(--line); padding-top: 28px; margin-top: 56px; }
.related-notes h2 { font-size: 18px; }
.section .related-list { list-style: none; padding: 0; margin: 12px 0 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 4px 32px; }
.related-list li { display: grid; gap: 2px; padding: 10px 0; border-bottom: 1px solid var(--line); }
.related-list a { font-size: 15px; font-weight: 600; color: var(--ink); }
.related-list a:hover { color: var(--brand); }
.related-list .muted { font-size: 13px; }
.related-notes + .source-notes { margin-top: 24px; }
@media (max-width: 610px) { .related-list { grid-template-columns: 1fr; } }