@charset "UTF-8";
:root {
  --paper: #f7f6f0;
  --white: #fffefa;
  --ink: #172a24;
  --muted: #69746a;
  --forest: #173e35;
  --green: #3f7160;
  --wash: #e8ede1;
  --line: #dfe2d6;
  --serif: "Songti SC", "STSong", "Noto Serif CJK SC", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 34px; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--sans); font-size: 16px; line-height: 1.7; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; }
button, a, input { -webkit-tap-highlight-color: transparent; }
button:focus-visible, a:focus-visible, input:focus-visible { outline: 3px solid #79a58e; outline-offset: 5px; }
h1, h2, h3, p, figure { margin: 0; }
img { display: block; max-width: 100%; height: auto; }
[hidden] { display: none !important; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; z-index: 100; top: -60px; left: 20px; padding: 10px 20px; background: var(--forest); color: white; }
.skip-link:focus { top: 16px; }
.site-grid { display: grid; grid-template-columns: 254px minmax(0, 1fr); }
.sidebar { position: sticky; top: 0; height: 100dvh; min-height: 680px; padding: 42px 26px 24px; border-right: 1px solid var(--line); display: flex; flex-direction: column; background: #eeefe6; }
.brand { display: flex; align-items: center; gap: 11px; font-size: 18px; font-weight: 650; white-space: nowrap; }
.brand small { display: block; font-size: 8px; letter-spacing: 1.45px; font-weight: 500; margin-top: 4px; color: var(--muted); }
.book-mark { flex-shrink: 0; width: 36px; height: 41px; border: 1.5px solid var(--forest); border-radius: 2px 6px 6px 2px; display: inline-flex; align-items: center; justify-content: center; font: 25px Georgia, serif; color: var(--forest); position: relative; }
.book-mark::before { content: ""; position: absolute; left: 5px; top: 0; bottom: 0; border-left: 1px solid #a2b2a2; }
.book-mark span { position: absolute; right: -5px; bottom: -5px; font: 10px var(--sans); background: #eeefe6; padding: 1px 3px; }
.sidebar-intro { margin-top: 29px; font-size: 12px; line-height: 1.9; color: var(--muted); padding-left: 2px; }
.sidebar nav { margin-top: 37px; }
.nav-caption { display: flex; justify-content: space-between; align-items: center; font-size: 10px; letter-spacing: 1.8px; color: var(--muted); margin-bottom: 13px; }
.nav-caption span { font-size: 9px; letter-spacing: 0; }
.chapter-link { display: flex; align-items: center; gap: 12px; font-size: 13px; padding: 11px 10px; border-radius: 5px; margin: 4px -10px; color: #425447; }
.chapter-link:hover { background: #e2e7da; }
.chapter-link[aria-current] { color: #fffefa; background: var(--forest); }
.chapter-number { font: 11px Georgia, serif; opacity: .65; width: 18px; }
.chapter-arrow { margin-left: auto; font-size: 17px; opacity: 0; }
.chapter-link[aria-current] .chapter-arrow, .chapter-link:hover .chapter-arrow { opacity: 1; }
.sidebar-note { display: flex; align-items: flex-start; gap: 8px; margin-top: 30px; padding-top: 23px; border-top: 1px solid #d8ddce; font-size: 11px; color: #536554; }
.sidebar-note p span { color: #7c8578; font-size: 10px; }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: #648974; margin-top: 7px; }
.sidebar-bottom { margin-top: auto; padding-top: 30px; font-size: 10px; color: var(--muted); }
.register-button { display: flex; align-items: center; justify-content: space-between; gap: 16px; width: 100%; border: 1px solid #bdc8b8; background: transparent; color: #63755f; border-radius: 4px; padding: 10px 12px; font-size: 12px; opacity: .7; }
.sidebar-bottom > p { margin-top: 5px; }
.sidebar-bottom > a { display: inline-block; margin-top: 22px; }
.page-shell { width: 100%; min-width: 0; padding: 0 clamp(26px, 4.6vw, 78px); }
.topline { height: 88px; display: flex; align-items: center; justify-content: space-between; color: #7a8275; font-size: 9px; letter-spacing: 2px; border-bottom: 1px solid var(--line); }
.topline span:last-child { font-size: 10px; letter-spacing: 2px; }
main, .site-footer, .topline { max-width: 1260px; margin-left: auto; margin-right: auto; }
.mobile-header { display: none; }
.home-intro { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(300px, .9fr); gap: 38px; align-items: center; padding: 58px 0 56px; border-bottom: 1px solid var(--line); }
.eyebrow { display: flex; align-items: center; gap: 9px; font-size: 11px; letter-spacing: 1.2px; color: var(--green); line-height: 1.8; }
.eyebrow > span { width: 18px; height: 1px; background: var(--green); flex-shrink: 0; }
h1 { font-family: var(--serif); font-size: clamp(35px, 3.35vw, 58px); font-weight: 600; line-height: 1.38; letter-spacing: -.045em; margin-top: 19px; }
.hero-copy h1 { white-space: nowrap; }
.hero-copy h1 > span { color: var(--green); }
.hero-summary { color: #697467; font-size: 13px; line-height: 1.95; max-width: 420px; margin-top: 22px; }
.primary-link { display: inline-flex; gap: 27px; align-items: center; justify-content: space-between; background: var(--forest); color: var(--white); padding: 13px 20px; border-radius: 4px; font-size: 12px; line-height: 1.6; font-weight: 500; }
.primary-link:hover { background: #2b5648; }
.primary-link span { font-size: 18px; line-height: 1; }
.hero-copy .primary-link { margin-top: 27px; }
.small-note { font-size: 9px; color: #818879; margin-top: 13px; }
.hero-figure { border: 1px solid #d7ddcf; padding: 15px 17px 13px; background: #edf0e5; border-radius: 3px; transform: rotate(1deg); box-shadow: 4px 6px 0 #e2e5d8; }
.figure-topline { display: flex; justify-content: space-between; font-size: 7px; letter-spacing: 1.6px; color: #7d8877; border-bottom: 1px solid #d1d9c7; padding-bottom: 12px; }
.hero-figure img { width: 100%; }
.hero-figure figcaption { display: flex; align-items: center; gap: 7px; font-size: 8px; color: #7c8572; border-top: 1px solid #d1d9c7; padding-top: 10px; }
.figure-dot { width: 5px; height: 5px; background: #819575; border-radius: 50%; }
.home-section { padding-top: 46px; }
.section-heading { display: flex; align-items: flex-end; justify-content: space-between; gap: 25px; margin-bottom: 23px; }
.section-index { display: block; font-size: 9px; letter-spacing: 1.6px; color: #7b8a74; margin-bottom: 9px; }
h2 { font-family: var(--serif); font-size: 27px; font-weight: 600; letter-spacing: -.025em; line-height: 1.5; }
.section-heading > p { color: #858c80; font-size: 10px; padding-bottom: 5px; }
.device-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.device-card { display: grid; grid-template-columns: 45px 1fr 17px; gap: 18px; padding: 25px 23px 0; border: 1px solid #d7decf; border-radius: 4px; background: var(--white); transition: border-color .2s, transform .2s; }
.device-card:hover { border-color: #5f886e; transform: translateY(-3px); }
.device-icon { width: 44px; height: 51px; border-radius: 6px; background: #edf1e7; color: var(--forest); display: flex; align-items: center; justify-content: center; }
.device-icon svg { width: 23px; height: 32px; }
.card-kicker { display: block; font-size: 8px; letter-spacing: 1.7px; color: #83927a; margin-bottom: 6px; }
.device-card h3 { font-family: var(--serif); font-size: 23px; font-weight: 600; line-height: 1.2; }
.device-card p { font-size: 11px; line-height: 1.95; color: #7d8677; margin-top: 12px; }
.card-arrow { font-size: 19px; font-weight: 300; color: #5d7d63; }
.card-footer { grid-column: 1/-1; border-top: 1px solid var(--line); display: flex; justify-content: space-between; color: #506951; font-size: 10px; padding: 14px 0; margin-top: 3px; }
.card-footer span { color: #a3ad98; font-family: Georgia, serif; }
.task-list { border-top: 1px solid var(--line); }
.task-list > a { display: flex; align-items: center; gap: 23px; padding: 22px 6px; border-bottom: 1px solid var(--line); }
.task-list > a:hover { background: #eef0e6; }
.task-number { font: 19px Georgia, serif; color: #9ea993; min-width: 30px; }
.task-list h3 { font-size: 15px; font-weight: 550; }
.task-list p { color: #818979; font-size: 11px; margin-top: 3px; }
.task-list a > span:last-child { margin-left: auto; font-size: 22px; color: #52725b; padding-left: 10px; }
.preparation-grid { display: grid; grid-template-columns: minmax(200px, .73fr) minmax(0, 1.27fr); gap: 50px; align-items: start; margin-bottom: 50px; }
.preparation-intro h2 { font-size: 31px; }
.preparation-intro > p { font-size: 12px; color: #7b8575; line-height: 1.95; margin-top: 16px; max-width: 270px; }
.pencil-note { font-family: var(--serif); color: #7a9074; font-size: 18px; line-height: 1.8; margin-top: 26px; transform: rotate(-3deg); border-left: 2px solid #c3d0b8; padding-left: 16px; }
.checklist { border: 1px solid #d6dfcc; background: #fdfdf8; border-radius: 4px; padding: 21px 24px 17px; }
.checklist-heading { display: flex; justify-content: space-between; align-items: center; gap: 10px; font-size: 12px; }
.checklist-count { font-size: 10px; color: #849079; }
progress { appearance: none; width: 100%; height: 3px; border: 0; display: block; margin: 14px 0 9px; background: #e8eddf; }
progress::-webkit-progress-bar { background: #e8eddf; }
progress::-webkit-progress-value { background: #648d69; transition: width .2s; }
progress::-moz-progress-bar { background: #648d69; }
.checklist fieldset { border: 0; margin: 0; padding: 0; min-width: 0; }
.check-item { display: flex; align-items: flex-start; gap: 12px; cursor: pointer; font-size: 12px; color: #5a6f56; line-height: 1.8; padding: 11px 0; }
.check-item + .check-item { border-top: 1px dashed #e1e6d9; }
.check-item input { margin: 4px 0 0; width: 15px; height: 15px; flex-shrink: 0; accent-color: var(--green); cursor: pointer; }
.check-item input:checked + span { text-decoration: line-through; color: #8c9684; }
.checklist-bottom { display: flex; justify-content: space-between; gap: 8px; align-items: center; border-top: 1px solid #e2e7d9; margin-top: 10px; padding-top: 13px; }
.checklist-bottom > span { font-size: 9px; color: #8c9584; }
.reset-checklist { padding: 2px; border: 0; background: transparent; font-size: 10px; color: #587451; white-space: nowrap; }
.no-script-note { font-size: 10px; margin-top: 8px; }
.official-panel { display: flex; align-items: center; gap: 30px; justify-content: space-between; border-top: 1px solid #d4deca; border-bottom: 1px solid #d4deca; padding: 30px; background: #e8edde; }
.official-panel h2 { font-size: 25px; }
.official-panel p { color: #7c8974; font-size: 11px; line-height: 1.9; margin-top: 7px; max-width: 510px; }
.official-panel .primary-link { flex-shrink: 0; }
.sources-block { margin-top: 37px; padding-top: 26px; border-top: 1px solid var(--line); }
.sources-block h2 { font-size: 18px; }
.sources-block > p { font-size: 11px; color: #88907f; margin-top: 8px; line-height: 1.8; }
.sources-block ul { list-style: none; padding: 0; margin: 14px 0 0; display: flex; flex-wrap: wrap; gap: 10px 22px; }
.sources-block li a { font-size: 11px; color: #5f7a5b; text-decoration: underline; text-underline-offset: 4px; text-decoration-color: #bacbb0; }
.sources-block li a:hover { text-decoration-color: currentColor; }
.site-footer { margin-top: 58px; padding: 29px 0 22px; border-top: 1px solid #cfd8c5; }
.footer-title { display: flex; align-items: center; justify-content: space-between; margin-bottom: 21px; }
.footer-title > span { font-family: var(--serif); font-size: 21px; }
.footer-title > a { color: #74876e; font-size: 10px; }
.footer-columns { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.footer-columns p { color: #8b9282; font-size: 10px; line-height: 1.95; }
.footer-columns strong { display: block; color: #63765b; font-size: 11px; font-weight: 500; margin-bottom: 7px; }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; color: #98a08e; font-size: 8px; margin-top: 25px; padding-top: 15px; border-top: 1px solid #e1e5d9; }
.footer-bottom a { color: #778a6e; }
.chapter-header { padding-top: 33px; max-width: 940px; }
.back-link { display: inline-block; color: #83917a; font-size: 11px; margin-bottom: 31px; }
.chapter-header h1 { font-size: clamp(30px, 3.25vw, 52px); max-width: 810px; }
.chapter-summary { font-size: 15px; line-height: 1.95; color: #76816f; max-width: 790px; margin-top: 23px; }
.chapter-meta { display: flex; flex-wrap: wrap; gap: 18px; color: #8b9681; font-size: 9px; letter-spacing: 1px; margin-top: 23px; }
.chapter-figure { margin-top: 30px; }
.chapter-figure img { width: 100%; height: 340px; object-fit: contain; background: #edf0e5; border: 1px solid #d8e0ce; border-radius: 3px; }
.chapter-figure figcaption { color: #919b85; font-size: 9px; margin-top: 8px; }
.chapter-layout { display: grid; grid-template-columns: minmax(0, 1fr) 180px; gap: 52px; margin-top: 13px; }
.reading-section { margin-top: 35px; }
.reading-section h2 { font-size: 24px; margin-bottom: 19px; }
.reading-section > p { color: #677561; font-size: 14px; line-height: 2; margin-top: 15px; }
.action-steps { padding: 17px 24px 17px 39px; margin: 20px 0 0; border: 1px solid #dfe5d5; background: #f0f3e9; border-radius: 3px; }
.action-steps li { padding: 7px 0 7px 5px; font-size: 12px; color: #64785b; line-height: 1.8; }
.action-steps li::marker { font-family: Georgia, serif; color: #829774; }
.reading-note { display: flex; gap: 11px; border-left: 2px solid #b8cba8; margin-top: 21px; padding: 10px 0 10px 16px; color: #819575; }
.reading-note > span { font-size: 20px; line-height: 1.4; }
.reading-note p { font-size: 12px; line-height: 1.9; }
.page-toc { align-self: start; position: sticky; top: 33px; margin-top: 36px; border-left: 1px solid #d6dfcb; padding-left: 20px; }
.page-toc > p { font-size: 9px; letter-spacing: 1.8px; color: #8a997d; margin-bottom: 17px; }
.page-toc > a { display: block; font-size: 10px; color: #7c8b70; line-height: 1.85; margin-top: 13px; }
.page-toc > a:hover { color: var(--forest); }
.page-toc .toc-source { color: #47643c; border-top: 1px solid #d9e1cf; padding-top: 16px; margin-top: 20px; }
.chapter-checklist { margin-top: 44px; }
.chapter-checklist h2 { font-size: 26px; margin-bottom: 20px; }
.next-chapter { display: flex; align-items: center; justify-content: space-between; padding: 26px 29px; background: #e8edde; border: 1px solid #d3dec7; margin-top: 40px; border-radius: 3px; }
.next-chapter h2 { font-size: 24px; }
.next-chapter > span { font-size: 29px; color: #6c865e; }
.next-chapter:hover { background: #e1e9d5; }
.not-found { padding: 100px 0; min-height: 550px; }
.not-found p { max-width: 620px; margin: 25px 0; color: #7e8a73; }
@media (min-width: 1650px) {
  .site-grid { grid-template-columns: 285px minmax(0, 1fr); }
  .sidebar { padding-left: 34px; padding-right: 34px; }
  .home-intro { gap: 65px; padding-top: 70px; padding-bottom: 70px; }
  .hero-copy h1 { font-size: 60px; }
}
@media (max-width: 1220px) {
  .site-grid { grid-template-columns: 230px minmax(0, 1fr); }
  .sidebar { padding-left: 20px; padding-right: 20px; }
  .brand { font-size: 16px; }
  .home-intro { grid-template-columns: 1fr .85fr; gap: 28px; }
  .hero-copy h1 { font-size: 36px; }
  .hero-summary { font-size: 12px; }
  .device-card { gap: 12px; padding: 21px 18px 0; grid-template-columns: 37px 1fr 12px; }
  .device-icon { width: 36px; }
  .device-card h3 { font-size: 20px; }
  .device-card p { font-size: 10px; }
  .section-heading > p { display: none; }
  .chapter-layout { grid-template-columns: minmax(0, 1fr) 150px; gap: 28px; }
  .official-panel { padding: 25px; gap: 20px; }
  .official-panel h2 { font-size: 22px; }
}
@media (max-width: 980px) {
  html { scroll-padding-top: 90px; }
  .site-grid { display: block; }
  .mobile-header { display: flex; align-items: center; justify-content: space-between; position: sticky; top: 0; z-index: 50; height: 66px; padding: 0 28px; background: #eeefe6; border-bottom: 1px solid #d9dece; }
  .mobile-brand { display: flex; gap: 11px; align-items: center; font-size: 16px; font-weight: 600; }
  .mobile-header .book-mark { width: 29px; height: 33px; font-size: 21px; }
  .menu-toggle { border: 0; color: #45613f; padding: 7px 0 7px 16px; font-size: 12px; background: transparent; }
  .menu-toggle span { margin-left: 8px; }
  .sidebar { position: fixed; top: 66px; left: 0; height: calc(100dvh - 66px); min-height: 0; width: 272px; padding: 28px; z-index: 45; transform: translateX(-101%); visibility: hidden; overflow-y: auto; transition: transform .2s, visibility .2s; }
  .sidebar.is-open { transform: translateX(0); visibility: visible; }
  .sidebar > .brand { display: none; }
  .sidebar-intro { margin-top: 0; }
  .sidebar nav { margin-top: 25px; }
  .sidebar-note { margin-top: 20px; padding-top: 18px; }
  .sidebar-bottom { padding-top: 24px; }
  .sidebar-bottom > a { margin-top: 13px; }
  .menu-scrim { position: fixed; inset: 66px 0 0; z-index: 40; border: 0; background: rgb(20 38 25 / 35%); }
  body.menu-open { overflow: hidden; }
  .page-shell { padding: 0 34px; }
  .topline { height: 57px; font-size: 8px; }
  .home-intro { padding-top: 44px; padding-bottom: 43px; gap: 36px; }
  .hero-copy h1 { font-size: 37px; }
  .hero-figure { padding: 13px; }
  .home-section { padding-top: 39px; }
  .preparation-grid { gap: 35px; }
  .chapter-figure img { height: 320px; }
  .chapter-layout { grid-template-columns: minmax(0, 1fr) 160px; gap: 34px; }
}
@media (max-width: 660px) {
  .mobile-header { padding: 0 21px; height: 61px; }
  .mobile-brand { font-size: 15px; }
  .sidebar { top: 61px; height: calc(100dvh - 61px); }
  .menu-scrim { top: 61px; }
  .page-shell { padding: 0 23px; }
  .topline { height: 48px; font-size: 7px; letter-spacing: 1.5px; }
  .topline span:last-child { font-size: 8px; letter-spacing: 1px; }
  .home-intro { grid-template-columns: 1fr; gap: 31px; padding-top: 34px; padding-bottom: 36px; }
  .eyebrow { font-size: 10px; letter-spacing: .8px; }
  .hero-copy h1 { font-size: clamp(33px, 8.8vw, 47px); margin-top: 17px; letter-spacing: -.05em; }
  .hero-summary { font-size: 13px; margin-top: 18px; max-width: 420px; }
  .hero-copy .primary-link { margin-top: 22px; }
  .small-note { font-size: 9px; }
  .hero-figure { transform: none; width: 100%; max-width: 490px; }
  .hero-figure img { width: 100%; max-height: 250px; object-fit: contain; }
  .figure-topline { padding-bottom: 10px; }
  .hero-figure figcaption { font-size: 8px; padding-top: 8px; }
  h2 { font-size: 25px; }
  .home-section { padding-top: 34px; }
  .section-heading { margin-bottom: 18px; }
  .section-index { font-size: 8px; margin-bottom: 8px; }
  .device-grid { grid-template-columns: 1fr; gap: 13px; }
  .device-card { padding: 23px 22px 0; grid-template-columns: 42px 1fr 15px; gap: 16px; }
  .device-card h3 { font-size: 24px; }
  .device-card p { font-size: 12px; margin-top: 9px; }
  .device-icon { width: 42px; height: 48px; }
  .card-footer { font-size: 11px; padding: 12px 0; }
  .task-list > a { gap: 13px; padding: 19px 2px; }
  .task-number { min-width: 23px; font-size: 17px; }
  .task-list h3 { font-size: 14px; }
  .task-list p { font-size: 11px; line-height: 1.8; }
  .task-list a > span:last-child { font-size: 20px; }
  .preparation-grid { grid-template-columns: 1fr; gap: 23px; margin-bottom: 35px; }
  .preparation-intro h2 { font-size: 28px; }
  .preparation-intro h2 br { display: none; }
  .preparation-intro > p { max-width: none; font-size: 12px; margin-top: 10px; }
  .pencil-note { display: none; }
  .checklist { padding: 19px 18px 16px; }
  .check-item { font-size: 12px; }
  .official-panel { flex-direction: column; align-items: flex-start; gap: 22px; padding: 25px 22px; }
  .official-panel h2 { font-size: 23px; }
  .official-panel p { font-size: 12px; }
  .sources-block { margin-top: 30px; padding-top: 22px; }
  .sources-block ul { flex-direction: column; gap: 7px; }
  .sources-block li a { font-size: 11px; }
  .site-footer { margin-top: 36px; padding-top: 24px; }
  .footer-columns { grid-template-columns: 1fr; gap: 18px; }
  .footer-columns p { font-size: 10px; }
  .footer-columns strong { margin-bottom: 5px; }
  .footer-bottom { gap: 9px 14px; font-size: 8px; }
  .chapter-header { padding-top: 22px; }
  .back-link { margin-bottom: 22px; font-size: 10px; }
  .chapter-header .eyebrow { font-size: 8px; letter-spacing: .6px; }
  .chapter-header h1 { font-size: 33px; line-height: 1.4; margin-top: 16px; }
  .chapter-summary { font-size: 13px; line-height: 1.95; margin-top: 18px; }
  .chapter-meta { font-size: 8px; gap: 12px; letter-spacing: .5px; margin-top: 18px; }
  .chapter-figure { margin-top: 24px; }
  .chapter-figure img { height: auto; aspect-ratio: 3 / 2; object-fit: contain; }
  .chapter-figure figcaption { font-size: 8px; }
  .chapter-layout { display: block; margin-top: 0; }
  .page-toc { display: none; }
  .reading-section { margin-top: 29px; }
  .reading-section h2 { font-size: 23px; margin-bottom: 16px; }
  .reading-section > p { font-size: 14px; line-height: 2; }
  .reading-note p { font-size: 12px; }
  .action-steps { padding: 13px 18px 13px 31px; }
  .chapter-checklist { margin-top: 34px; }
  .next-chapter { margin-top: 28px; padding: 23px; }
  .next-chapter h2 { font-size: 23px; }
  .not-found { padding: 65px 0; min-height: 450px; }
  .not-found h1 { font-size: 33px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}