:root {
  color-scheme: dark;
  --paper: #080f1a; --panel: #101f2e; --ink: #e8f1f6;
  --muted: #a2b4c5; --line: #2b4052; --cyan: #83dbee; --amber: #f0bc75;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", system-ui, sans-serif;
  color: var(--ink); background: var(--paper);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 28px; }
body { margin: 0; }
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 5px; }
a:hover { color: var(--cyan); }
a:focus-visible, summary:focus-visible, [tabindex]:focus-visible { outline: 2px solid var(--cyan); outline-offset: 5px; }
.skip-link { position: absolute; top: -90px; left: 16px; z-index: 10; padding: 14px; background: var(--paper); }
.skip-link:focus { top: 12px; }
.review-strip { display: flex; justify-content: center; gap: 18px; padding: 11px 20px; background: #26303a; color: #d7dfe5; font-size: 12px; }
.review-strip span { color: var(--amber); font-weight: 700; }
.review-strip a { margin-left: 14px; }
.reading-header { max-width: 1240px; margin: auto; padding: 26px 36px; display: flex; justify-content: space-between; align-items: center; border-bottom: 1px solid var(--line); }
.reading-brand { display: flex; gap: 12px; align-items: center; text-decoration: none; font-size: 20px; font-weight: 700; }
.reading-brand small { display: block; color: var(--muted); font-size: 10px; font-weight: 400; letter-spacing: .14em; margin-top: 4px; }
.brand-symbol { display: block; width: 22px; height: 30px; background: var(--cyan); clip-path: polygon(12% 100%, 45% 0, 100% 100%, 72% 100%, 43% 39%, 30% 100%); }
.reading-header nav { display: flex; gap: 28px; color: #c1d0db; font-size: 13px; }
.reading-header nav a { text-decoration: none; }
.reading-main { max-width: 1240px; margin: auto; padding: 0 36px; }
.breadcrumbs { padding-top: 26px; display: flex; gap: 12px; align-items: center; color: var(--muted); font-size: 12px; }
.breadcrumbs a { text-decoration: none; }
.article-hero { display: grid; grid-template-columns: minmax(0, 1fr) 272px; gap: 58px; align-items: end; padding: 46px 0 40px; }
.article-kind { margin: 0 0 22px; color: var(--cyan); font-size: 13px; font-weight: 600; }
.article-kind span { color: var(--muted); border-left: 1px solid var(--line); padding-left: 13px; margin-left: 13px; font-weight: 400; }
h1 { margin: 0; font-size: clamp(30px, 3.2vw, 46px); line-height: 1.38; letter-spacing: -.035em; font-weight: 750; text-wrap: balance; }
.article-lead { color: #b4c4d2; font-size: 16px; line-height: 1.9; margin: 24px 0; max-width: 720px; }
.article-meta { display: flex; flex-wrap: wrap; gap: 10px 22px; font-size: 11px; color: var(--muted); }
.answer-note { border-top: 2px solid var(--cyan); background: var(--panel); padding: 23px 24px; }
.note-label { color: var(--cyan); font-size: 13px; font-weight: 700; }
.answer-note p { margin: 14px 0 18px; line-height: 1.9; font-size: 14px; }
.answer-note small { font-size: 10px; color: var(--muted); }
.concept-map { display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--line); background: #0b1724; margin-bottom: 48px; }
.concept { padding: 24px 28px; position: relative; }
.concept + .concept { border-left: 1px solid var(--line); }
.concept h2 { display: flex; justify-content: space-between; gap: 12px; margin: 0; align-items: center; font-size: 21px; }
.concept h2 span { font-size: 11px; font-weight: 400; color: var(--cyan); }
.concept p { font-size: 13px; line-height: 1.85; color: var(--muted); margin: 12px 0 0; }
.reading-layout { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 56px; align-items: start; padding-bottom: 72px; }
.desktop-toc { position: sticky; top: 28px; border-top: 1px solid var(--line); }
.desktop-toc nav > p { color: #d8e4ed; font-size: 12px; margin: 22px 0 18px; }
.desktop-toc ol, .mobile-toc ol { padding: 0; list-style: none; margin: 0; }
.desktop-toc li { padding: 0 0 17px; }
.desktop-toc a, .mobile-toc a { font-size: 12px; line-height: 1.7; color: var(--muted); text-decoration: none; }
.desktop-toc a:hover, .mobile-toc a:hover { color: var(--cyan); }
.article-body { max-width: 840px; }
.article-body section { margin: 0 0 46px; }
.article-body h2 { margin: 0 0 20px; font-size: 25px; line-height: 1.5; letter-spacing: -.02em; }
.article-body p, .reading-list { color: #bdccd8; font-size: 15px; line-height: 2; }
.article-body p { margin: 0 0 18px; }
.reading-list { padding-left: 22px; }
.reading-list li { padding-left: 6px; margin: 10px 0; }
.reading-list li::marker { color: var(--cyan); }
.table-scroll { overflow-x: auto; margin: 24px 0; border: 1px solid var(--line); }
table { width: 100%; border-collapse: collapse; text-align: left; line-height: 1.8; font-size: 13px; }
th { background: #142333; padding: 15px 17px; font-weight: 600; color: #e0eaf2; }
td { padding: 17px; color: #b7c9d8; vertical-align: top; border-top: 1px solid var(--line); }
td:first-child { color: var(--ink); width: 28%; }
.task-flow { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; list-style: none; padding: 0; margin: 28px 0 14px; }
.task-flow li { text-align: center; border: 1px solid #365a6a; background: #10232f; padding: 18px 8px; color: #b9e9f2; font-size: 12px; position: relative; }
.task-flow li + li::before { content: "›"; position: absolute; left: -10px; color: var(--muted); }
.article-body .caption, .caption { font-size: 12px; color: #91a7ba; line-height: 1.8; }
.article-body .section-source { color: #91a7ba; font-size: 12px; margin-top: 17px; }
.article-figure { margin: 28px 0; border: 1px solid var(--line); background: var(--panel); }
.article-figure > a { display: block; }
.article-figure > .figure-checkerboard { background-color: #233340; background-image: conic-gradient(#40515e 25%, transparent 0 50%, #40515e 0 75%, transparent 0); background-size: 24px 24px; }
.article-figure img { display: block; width: 100%; height: auto; }
.article-figure figcaption { padding: 16px 20px; color: #b4c4d2; font-size: 13px; line-height: 1.85; }
.article-link a { color: var(--cyan); text-underline-offset: 4px; overflow-wrap: anywhere; }
.section-source a { color: #91bacc; }
.source-section { border-top: 1px solid var(--line); padding-top: 30px; }
.source-section ol { padding-left: 23px; color: var(--cyan); font-size: 14px; line-height: 2.3; }
.reading-next { padding: 26px 30px; background: var(--panel); border-left: 2px solid var(--cyan); }
.reading-next strong { font-size: 19px; }
.reading-next p { margin-top: 12px; font-size: 13px; }
.reading-next > a { display: inline-block; color: var(--cyan); font-size: 13px; margin: 2px 0 4px; }
.reading-footer { max-width: 1168px; margin: auto; padding: 30px 0 40px; border-top: 1px solid var(--line); display: flex; gap: 25px; align-items: center; color: var(--muted); font-size: 12px; }
.reading-footer p { flex: 1; margin: 0; }
.reading-footer > a { text-decoration: none; }
.mobile-toc { display: none; }
.review-main { max-width: 1050px; padding: 60px 36px 80px; margin: auto; }
.review-main h1 { font-size: clamp(28px, 4vw, 45px); }
.review-main h2 { margin: 45px 0 22px; font-size: 22px; }
.review-facts { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; margin: 40px 0; }
.review-facts div { border-top: 1px solid var(--line); padding-top: 19px; }
.review-facts b { color: var(--cyan); font-size: 13px; }
.review-facts p { font-size: 14px; line-height: 1.9; color: var(--muted); }
.review-article { display: block; padding: 27px 30px; border: 1px solid var(--line); background: var(--panel); text-decoration: none; }
.review-article > span, .review-article > b { font-size: 12px; color: var(--cyan); }
.review-article h3 { font-size: 25px; margin: 16px 0; line-height: 1.6; }
.review-article p { font-size: 14px; color: var(--muted); line-height: 1.8; margin-bottom: 24px; }
.review-article + .review-article { margin-top: 18px; }
.brief-template { margin: 24px 0; border: 1px solid var(--line); background: #0d1a28; }
.brief-template .template-label { margin: 0; padding: 13px 20px; border-bottom: 1px solid var(--line); color: var(--cyan); font-size: 12px; }
.brief-template pre { margin: 0; padding: 22px; white-space: pre-wrap; overflow-wrap: anywhere; line-height: 1.9; font-family: inherit; font-size: 14px; color: #c9d8e4; }
@media (max-width: 960px) {
  .article-hero { grid-template-columns: 1fr; gap: 28px; }
  .answer-note { padding: 20px 24px; }
  .answer-note p { margin-bottom: 10px; }
  .reading-layout { grid-template-columns: 170px minmax(0, 1fr); gap: 30px; }
  .concept { padding: 20px; }
  .concept h2 { display: block; }
  .concept h2 span { display: block; margin-top: 8px; }
  .reading-footer { margin: 0 36px; }
}
@media (max-width: 640px) {
  .reading-header { padding: 20px; }
  .reading-header nav { gap: 16px; font-size: 12px; }
  .reading-brand { font-size: 18px; gap: 8px; }
  .reading-brand small { font-size: 9px; letter-spacing: .05em; }
  .reading-main { padding: 0 20px; }
  .breadcrumbs { padding-top: 22px; font-size: 11px; }
  .article-hero { padding: 30px 0 26px; }
  .article-kind { margin-bottom: 17px; }
  h1 { font-size: 30px; line-height: 1.43; }
  .article-lead { font-size: 15px; }
  .article-meta { gap: 10px 14px; }
  .concept-map { grid-template-columns: 1fr; margin-bottom: 26px; }
  .concept { padding: 18px 22px; }
  .concept + .concept { border-left: 0; border-top: 1px solid var(--line); }
  .concept h2 { display: flex; font-size: 19px; }
  .concept h2 span { display: inline; margin-top: 0; }
  .reading-layout { display: block; padding-bottom: 40px; }
  .desktop-toc { display: none; }
  .mobile-toc { display: block; margin: 0 0 34px; padding: 16px 18px; border: 1px solid var(--line); }
  .mobile-toc summary { cursor: pointer; font-size: 14px; color: var(--cyan); }
  .mobile-toc li { padding-top: 14px; }
  .article-body h2 { font-size: 22px; }
  .article-body p, .reading-list { font-size: 15px; line-height: 1.95; }
  th, td { padding: 12px 10px; }
  table { min-width: 460px; }
  .task-flow { grid-template-columns: 1fr 1fr; gap: 10px; }
  .task-flow li::before { display: none; }
  .reading-footer { margin: 0 20px; flex-wrap: wrap; gap: 15px; line-height: 1.8; }
  .reading-footer p { flex-basis: 70%; }
  .review-strip { gap: 10px; font-size: 10px; padding: 10px; }
  .review-strip a { margin-left: 2px; }
  .review-main { padding: 38px 20px 50px; }
  .review-facts { grid-template-columns: 1fr; gap: 12px; }
  .review-article { padding: 22px; }
  .review-article h3 { font-size: 21px; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }