:root {
  --paper: #fffefa;
  --background: #f7f6f2;
  --ink: #25302f;
  --muted: #747a73;
  --accent: #b6533e;
  --accent-light: #f7ece6;
  --line: #e6e5dc;
  --sans: "Noto Sans SC", "Source Han Sans SC", "Microsoft YaHei", "PingFang SC", sans-serif;
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 104px; }
body { margin: 0; background: var(--background); color: var(--ink); font-family: var(--sans); -webkit-font-smoothing: antialiased; }
body::before { content: ""; position: absolute; inset: 76px 0 auto; height: 540px; pointer-events: none; background: radial-gradient(ellipse at 78% 0%, #e9ede4aa, transparent 60%); z-index: -1; }
a { color: inherit; text-underline-offset: 5px; }
a:focus-visible, button:focus-visible, summary:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; }
::selection { color: #332f27; background: #f0dacb; }
.skip-link { position: fixed; top: -60px; left: 16px; padding: 12px 18px; background: var(--ink); color: white; z-index: 100; }
.skip-link:focus { top: 14px; }
.site-header { height: 76px; position: sticky; top: 0; z-index: 20; border-bottom: 1px solid var(--line); background: #f7f6f2f2; backdrop-filter: blur(14px); }
.header-inner { max-width: 1280px; padding: 0 48px; height: 100%; margin: auto; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.wordmark { font-family: Georgia, "Times New Roman", serif; font-size: 26px; font-weight: 700; letter-spacing: -1.1px; text-decoration: none; white-space: nowrap; }
.wordmark span { color: var(--accent); }
.top-nav { display: flex; align-items: center; gap: 28px; font-size: 13px; }
.top-nav a { text-decoration: none; color: #53615b; }
.top-nav a:hover { color: var(--accent); }
.top-nav .visit-link { border: 1px solid #c5ccc0; border-radius: 6px; padding: 9px 15px; }
.reading-track { height: 2px; position: absolute; bottom: -1px; width: 100%; background: transparent; }
.reading-progress { height: 100%; width: 0; background: var(--accent); }
.page-shell { max-width: 1280px; margin: auto; padding: 0 48px; }
.article-hero { padding: 66px 0 45px; border-bottom: 1px solid var(--line); }
.breadcrumb { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; font-size: 12px; color: var(--muted); margin-bottom: 30px; }
.breadcrumb a { text-decoration: none; }
.breadcrumb span[aria-hidden] { color: #b5b9b1; }
.eyebrow { font-size: 11px; text-transform: uppercase; font-weight: 600; letter-spacing: 2.2px; display: flex; align-items: center; gap: 10px; color: var(--accent); margin-bottom: 18px; }
.eyebrow::before { content: ""; width: 25px; height: 1px; background: currentColor; }
h1 { font-family: var(--serif); font-weight: 600; font-size: clamp(32px, 3.45vw, 48px); line-height: 1.5; letter-spacing: -.035em; max-width: 990px; margin: 0 0 27px; text-wrap: balance; }
.article-meta { display: flex; flex-wrap: wrap; gap: 10px 20px; align-items: center; color: var(--muted); font-size: 12px; }
.article-meta .divider { width: 1px; height: 12px; background: #d4d7ce; }
.article-meta .author { display: flex; align-items: center; gap: 8px; color: #526158; }
.author-dot { width: 7px; height: 7px; border-radius: 50%; background: #738673; }
.article-layout { display: grid; grid-template-columns: minmax(0, 780px) minmax(190px, 1fr); gap: 72px; align-items: start; padding-top: 44px; }
.article-body { font-size: 16.5px; line-height: 2.02; min-width: 0; padding-bottom: 60px; }
.article-body > p { margin: 0 0 23px; }
.article-body > p:first-child { font-size: 19px; line-height: 1.95; margin-bottom: 27px; }
.article-body > p:first-child strong { font-weight: 500; }
.article-body strong { font-weight: 650; color: #1c2d27; }
.article-body h2 { font-size: 25px; line-height: 1.65; margin: 58px 0 23px; letter-spacing: -.025em; padding-top: 20px; border-top: 1px solid var(--line); }
.article-body h2:first-of-type { margin-top: 41px; }
.article-body h3 { font-size: 19px; line-height: 1.75; margin: 35px 0 15px; font-weight: 650; }
.article-body a { color: var(--accent); text-decoration-thickness: 1px; }
.article-body a:hover { color: #773c2e; }
.article-body ul, .article-body ol { padding-left: 1.5em; margin: 21px 0 25px; }
.article-body li { padding-left: .25em; margin-bottom: 12px; }
.article-body li::marker { color: #84917f; font-weight: 600; }
.article-body blockquote { margin: 27px 0; padding: 17px 23px; border-left: 3px solid var(--accent); background: var(--accent-light); font-size: 15px; line-height: 2; color: #5c443a; }
.article-body blockquote p { margin: 0; }
.table-scroll { overflow-x: auto; margin: 28px 0 30px; border: 1px solid var(--line); border-radius: 5px; background: var(--paper); }
.article-body table { border-collapse: collapse; width: 100%; font-size: 14px; line-height: 1.9; }
.article-body th { background: #eaf0e7; color: #405442; font-weight: 600; text-align: left; padding: 14px 16px; }
.article-body td { padding: 17px 16px; border-top: 1px solid var(--line); vertical-align: top; }
.article-body th:first-child { width: 31%; }
.article-body tr:nth-child(even) td { background: #fafaf5; }
.article-body section.faq-section { margin-top: 0; }
.faq-section h3 { padding-top: 25px; border-top: 1px dashed #e3e4da; margin-top: 29px; }
.faq-section > h3:first-of-type { border-top: none; padding-top: 0; }
.faq-section p { margin: 0 0 20px; }
.article-toc { position: sticky; top: 112px; padding-left: 24px; border-left: 1px solid var(--line); }
.toc-heading { margin: 0 0 18px; color: #8a8f82; font-size: 11px; font-weight: 600; letter-spacing: 2px; }
.toc-list { padding: 0; margin: 0; list-style: none; }
.toc-list li { margin: 0 0 14px; }
.toc-list a { display: block; color: #727c70; font-size: 12px; line-height: 1.9; text-decoration: none; transition: color .15s; }
.toc-list a:hover, .toc-list a[aria-current="location"] { color: var(--accent); }
.toc-actions { border-top: 1px solid var(--line); margin-top: 25px; padding-top: 19px; display: flex; flex-wrap: wrap; gap: 15px; }
.text-button { padding: 0; border: 0; background: none; color: #7b8074; cursor: pointer; font-size: 11px; font-family: var(--sans); }
.text-button:hover { color: var(--accent); }
.share-status { min-height: 18px; font-size: 10px; color: var(--muted); margin-top: 10px; }
.mobile-toc { display: none; }
.article-end { border-top: 1px solid var(--line); padding: 31px 0 45px; display: flex; justify-content: space-between; gap: 24px; align-items: center; }
.end-label { font-family: Georgia, serif; font-size: 22px; letter-spacing: -.7px; margin: 0 0 7px; }
.end-note { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.8; }
.end-link { display: inline-flex; align-items: center; gap: 22px; border: 1px solid #b9c5b5; color: #405744; text-decoration: none; padding: 12px 19px; border-radius: 5px; font-size: 12px; white-space: nowrap; }
.end-link:hover { background: #eaf0e7; }
.site-footer { border-top: 1px solid var(--line); font-size: 10px; color: #90958c; padding: 22px 0 28px; }
.footer-inner { display: flex; justify-content: space-between; gap: 20px; }
.site-footer a { color: #727d6d; text-decoration: none; }
@media (min-width: 1000px) and (prefers-reduced-motion: no-preference) {
  .article-hero { animation: enter .55s ease-out both; }
  .article-layout { animation: enter .65s .1s ease-out both; }
  @keyframes enter { from { opacity: 0; transform: translateY(9px); } to { opacity: 1; transform: translateY(0); } }
}
@media (max-width: 1000px) {
  .header-inner, .page-shell { padding-left: 32px; padding-right: 32px; }
  .article-layout { grid-template-columns: minmax(0, 1fr) 180px; gap: 35px; }
  .article-toc { padding-left: 17px; }
  .article-body { font-size: 16px; }
}
@media (max-width: 760px) {
  html { scroll-padding-top: 88px; }
  .site-header { height: 64px; }
  .header-inner, .page-shell { padding-left: 22px; padding-right: 22px; }
  .wordmark { font-size: 23px; }
  .top-nav { gap: 16px; font-size: 11px; }
  .top-nav .feature-link { display: none; }
  .top-nav .visit-link { padding: 7px 10px; }
  .article-hero { padding-top: 35px; padding-bottom: 28px; }
  .breadcrumb { font-size: 11px; margin-bottom: 25px; gap: 9px; }
  .eyebrow { font-size: 10px; letter-spacing: 1.7px; margin-bottom: 14px; }
  h1 { font-size: 31px; line-height: 1.58; margin-bottom: 23px; }
  .article-meta { font-size: 10px; gap: 10px 13px; }
  .article-meta .divider { height: 10px; }
  .article-layout { display: block; padding-top: 27px; }
  .article-toc { display: none; }
  .mobile-toc { display: block; margin-bottom: 27px; border: 1px solid var(--line); border-radius: 5px; background: #f0f2eb; font-size: 12px; }
  .mobile-toc summary { padding: 13px 15px; color: #52634c; cursor: pointer; }
  .mobile-toc nav { padding: 0 15px 7px; }
  .mobile-toc .toc-list a { font-size: 12px; }
  .article-body { font-size: 15.5px; line-height: 2.02; padding-bottom: 35px; }
  .article-body > p:first-child { font-size: 17px; }
  .article-body h2 { font-size: 22px; margin-top: 43px; padding-top: 19px; }
  .article-body h3 { font-size: 17px; margin-top: 29px; }
  .article-body table { font-size: 12px; line-height: 1.85; }
  .article-body th, .article-body td { padding: 12px 10px; }
  .article-body blockquote { font-size: 14px; padding: 15px 17px; }
  .article-body li { margin-bottom: 12px; }
  .article-end { display: block; padding-top: 24px; }
  .end-link { margin-top: 20px; }
  .footer-inner { flex-direction: column; gap: 9px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}
@media print {
  body { background: white; color: black; }
  .site-header, .article-toc, .mobile-toc, .article-end, .site-footer, .skip-link { display: none; }
  .page-shell { max-width: none; padding: 0; }
  .article-hero { padding: 0 0 20px; }
  .article-layout { display: block; padding-top: 20px; }
  .article-body { font-size: 11pt; line-height: 1.8; }
  h1 { font-size: 25pt; }
  .article-body h2 { font-size: 16pt; break-after: avoid; }
  .article-body h3 { font-size: 13pt; break-after: avoid; }
  .article-body table, blockquote { break-inside: avoid; }
  .table-scroll { overflow: visible; }
}