:root {
  --ink: #171a1d;
  --muted: #626a70;
  --line: #d8ddda;
  --paper: #f7f8f5;
  --white: #ffffff;
  --jade: #087c62;
  --jade-dark: #075f4d;
  --blue: #2654c7;
  --red: #c83f38;
  --yellow: #f1c84b;
  --max: 1180px;
  --header: 72px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 92px; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif; line-height: 1.65; letter-spacing: 0; }
body.menu-open { overflow: hidden; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button, input { font: inherit; }
.skip-link { position: fixed; left: 16px; top: -60px; z-index: 100; padding: 10px 14px; color: #fff; background: var(--ink); }
.skip-link:focus { top: 12px; }

.site-header { position: sticky; top: 0; z-index: 50; height: var(--header); border-bottom: 1px solid var(--line); background: rgba(247, 248, 245, .96); }
.header-inner { width: min(calc(100% - 48px), var(--max)); height: 100%; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; white-space: nowrap; }
.brand img { width: 42px; height: 42px; }
.site-nav { display: flex; align-items: center; gap: 6px; }
.site-nav a { position: relative; display: flex; align-items: center; min-height: 40px; padding: 7px 13px; color: #4d555a; font-size: 14px; font-weight: 700; }
.site-nav a:not(.nav-download)::after { content: ""; position: absolute; left: 13px; right: 13px; bottom: 4px; height: 2px; background: var(--jade); transform: scaleX(0); transform-origin: left; transition: transform .2s ease; }
.site-nav a:hover::after, .site-nav a.active::after { transform: scaleX(1); }
.site-nav a.active { color: var(--ink); }
.site-nav .nav-download { margin-left: 8px; padding: 8px 18px; color: #fff; background: var(--jade); }
.site-nav .nav-download:hover { background: var(--jade-dark); }
.menu-toggle { display: none; width: 42px; height: 42px; padding: 9px; border: 1px solid var(--line); background: var(--white); cursor: pointer; }
.menu-toggle span { display: block; height: 2px; margin: 5px 0; background: var(--ink); transition: transform .2s ease, opacity .2s ease; }

.hero { border-bottom: 1px solid var(--line); background: linear-gradient(90deg, #f7f8f5 0 66%, #eef1ed 66% 100%); }
.hero-inner { width: min(calc(100% - 48px), var(--max)); min-height: 650px; margin: 0 auto; display: grid; grid-template-columns: minmax(0, 1.14fr) minmax(360px, .86fr); gap: 56px; align-items: center; padding: 42px 0 48px; }
.hero-copy { max-width: 650px; }
.eyebrow { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; font-size: 12px; text-transform: uppercase; }
.eyebrow span { padding: 4px 8px; color: #fff; background: var(--blue); font-weight: 800; }
.eyebrow b { color: var(--muted); }
h1, h2, h3, p { margin-top: 0; }
.hero h1 { max-width: 630px; margin-bottom: 18px; font-size: 48px; line-height: 1.12; font-weight: 900; }
.hero h1 span { display: block; color: var(--jade); }
.hero-copy > p { max-width: 610px; margin-bottom: 24px; color: #40474c; font-size: 17px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 28px; }
.button { display: inline-flex; min-height: 46px; align-items: center; justify-content: center; padding: 10px 22px; border: 1px solid var(--ink); font-size: 15px; font-weight: 800; }
.button.primary { border-color: var(--jade); color: #fff; background: var(--jade); }
.button.primary:hover { border-color: var(--jade-dark); background: var(--jade-dark); }
.button.secondary { background: transparent; }
.button.secondary:hover { background: var(--white); }
.hero-facts { display: grid; grid-template-columns: repeat(3, 1fr); margin: 0; border-top: 1px solid var(--line); }
.hero-facts div { padding: 12px 14px 0 0; }
.hero-facts dt { color: var(--muted); font-size: 11px; font-weight: 800; }
.hero-facts dd { margin: 2px 0 0; font-size: 13px; font-weight: 800; }
.hero-media { position: relative; min-height: 500px; display: grid; grid-template-columns: 42px minmax(0, 1fr); align-items: center; justify-items: center; }
.spine-rail { align-self: stretch; display: flex; flex-direction: column; align-items: center; justify-content: space-around; border-left: 2px solid var(--ink); color: var(--muted); font-size: 10px; font-weight: 800; }
.spine-rail span { width: 34px; padding: 3px 0; border-top: 1px solid var(--ink); background: var(--paper); text-align: center; }
.hero-shot { position: relative; padding: 10px; border: 1px solid var(--ink); background: var(--white); box-shadow: 12px 12px 0 var(--blue); }
.hero-shot::before { content: ""; position: absolute; width: 10px; height: 10px; right: -6px; top: 44%; background: var(--red); }
.hero-shot img { width: 244px; height: auto; max-width: 400px; }
.edge-note { position: absolute; right: -9px; bottom: 40px; display: flex; flex-direction: column; padding: 8px 10px; border-left: 3px solid var(--red); background: var(--white); box-shadow: 0 6px 20px rgba(23, 26, 29, .11); font-size: 11px; }
.edge-note b { color: var(--blue); }

.section { padding: 78px 0; }
.section-inner { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; }
.section-heading { display: grid; grid-template-columns: 210px 1fr; align-items: end; margin-bottom: 34px; border-bottom: 1px solid var(--ink); }
.section-heading > span { padding-bottom: 10px; color: var(--blue); font-size: 11px; font-weight: 900; }
.section-heading h2 { margin: 0; padding-bottom: 8px; font-size: 30px; line-height: 1.2; }
.feature-section { background: var(--white); }
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.feature-item { min-height: 250px; padding: 24px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.feature-item:nth-child(even) { background: #f6f8f5; }
.feature-no { display: inline-flex; width: 28px; height: 28px; align-items: center; justify-content: center; margin-bottom: 36px; color: #fff; background: var(--blue); font-size: 12px; font-weight: 900; }
.feature-item:nth-child(2) .feature-no, .feature-item:nth-child(4) .feature-no { background: var(--red); }
.feature-item h3 { margin-bottom: 10px; font-size: 19px; }
.feature-item p { margin: 0; color: var(--muted); font-size: 14px; }

.route-section { background: #edf2ef; }
.route-layout { display: grid; grid-template-columns: 260px 1fr; column-gap: 64px; }
.route-layout .section-heading { grid-column: 1; display: block; margin: 0; border: 0; }
.route-layout .section-heading > span { display: block; }
.route-layout .section-heading h2 { margin-top: 12px; font-size: 34px; }
.route-list { grid-column: 2; grid-row: 1 / span 2; margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--ink); }
.route-list li { display: grid; grid-template-columns: 58px 1fr; gap: 20px; padding: 20px 0; border-bottom: 1px solid var(--line); }
.route-list li > span { color: var(--red); font-size: 12px; font-weight: 900; }
.route-list h3 { margin-bottom: 4px; font-size: 18px; }
.route-list p { margin: 0; color: var(--muted); font-size: 14px; }
.text-link { grid-column: 1; align-self: end; margin-top: 32px; color: var(--jade); font-weight: 800; }
.text-link span { padding-left: 6px; }

.gallery-section { background: var(--ink); color: var(--white); }
.gallery-section .section-heading { border-color: #596066; }
.gallery-section .section-heading > span { color: var(--yellow); }
.gallery-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; align-items: end; }
.gallery-card { margin: 0; }
.image-mat { height: 440px; display: flex; align-items: flex-end; justify-content: center; padding: 22px 18px 0; overflow: hidden; border: 1px solid #4e5559; background: #24292d; }
.gallery-card:nth-child(2) .image-mat { background: #123b35; }
.gallery-card:nth-child(3) .image-mat { background: #223156; }
.gallery-card img { width: auto; max-width: 400px; height: 418px; object-fit: contain; object-position: bottom; }
.gallery-card figcaption { display: grid; grid-template-columns: 120px 1fr; gap: 14px; padding: 14px 2px; border-bottom: 1px solid #4e5559; }
.gallery-card figcaption b { font-size: 14px; }
.gallery-card figcaption span { color: #b9c0c3; font-size: 12px; }

.notes-section { background: var(--white); }
.notes-layout { display: grid; grid-template-columns: 260px 1fr; column-gap: 64px; }
.notes-layout .section-heading { display: block; margin: 0; border: 0; }
.notes-layout .section-heading > span { display: block; }
.notes-layout .section-heading h2 { margin-top: 12px; }
.notes-board { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 3px solid var(--jade); }
.notes-board div { padding: 20px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.notes-board div:first-child { border-left: 1px solid var(--line); }
.notes-board b { font-size: 16px; }
.notes-board p { margin: 8px 0 0; color: var(--muted); font-size: 13px; }

.faq-preview { background: var(--paper); }
.faq-preview-grid { display: grid; border-top: 1px solid var(--ink); }
.faq-preview-grid a { display: grid; grid-template-columns: 60px 1fr 30px; align-items: center; min-height: 78px; border-bottom: 1px solid var(--line); }
.faq-preview-grid a:hover { background: var(--white); }
.faq-preview-grid span { color: var(--red); font-size: 12px; font-weight: 900; }
.faq-preview-grid b { font-size: 17px; }
.faq-preview-grid i { color: var(--jade); font-size: 22px; font-style: normal; }

.download-band { padding: 44px 0; color: #fff; background: var(--blue); }
.download-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.download-inner span { color: #d9e2ff; font-size: 11px; font-weight: 900; }
.download-inner h2 { margin: 5px 0 4px; font-size: 28px; }
.download-inner p { margin: 0; color: #d9e2ff; }
.download-band .button.primary { border-color: #fff; color: var(--ink); background: #fff; white-space: nowrap; }

.site-footer { padding: 34px 24px 20px; border-top: 1px solid var(--line); background: #eef0ed; text-align: center; }
.footer-inner { width: min(100%, var(--max)); margin: 0 auto 24px; display: flex; align-items: center; justify-content: space-between; }
.footer-brand { display: flex; align-items: center; gap: 9px; }
.footer-brand img { width: 34px; height: 34px; }
.footer-inner nav { display: flex; gap: 24px; color: var(--muted); font-size: 13px; }
.footer-inner nav a:hover { color: var(--jade); }
.disclaimer, .copyright { text-align: center; }
.disclaimer { margin: 0 auto 4px; color: #6b7276; font-size: 12px; }
.copyright { margin: 0; color: #868c8f; font-size: 11px; }

.page-hero { border-bottom: 1px solid var(--line); background: var(--white); }
.page-hero-inner { width: min(calc(100% - 48px), var(--max)); min-height: 330px; margin: 0 auto; display: grid; grid-template-columns: 1fr 180px; gap: 50px; align-items: center; padding: 52px 0; }
.page-kicker { color: var(--blue); font-size: 11px; font-weight: 900; }
.page-hero h1 { margin: 12px 0 14px; font-size: 42px; line-height: 1.2; }
.page-hero p { max-width: 760px; margin: 0; color: var(--muted); font-size: 16px; }
.page-index { height: 150px; display: flex; flex-direction: column; align-items: center; justify-content: center; border-left: 2px solid var(--ink); border-right: 1px solid var(--line); background: #f0f4f1; }
.page-index b { color: var(--jade); font-size: 48px; line-height: 1; }
.page-index span { margin-top: 10px; color: var(--muted); font-size: 12px; font-weight: 800; }

.article-section { padding: 62px 0 86px; }
.article-layout { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; display: grid; grid-template-columns: 220px minmax(0, 760px); gap: 74px; justify-content: center; }
.article-nav { position: sticky; top: 104px; align-self: start; display: grid; border-top: 3px solid var(--jade); }
.article-nav b { padding: 14px 12px; border-bottom: 1px solid var(--line); }
.article-nav a { padding: 10px 12px; border-bottom: 1px solid var(--line); color: var(--muted); font-size: 13px; }
.article-nav a:hover { color: var(--jade); background: var(--white); }
.prose > section { padding: 0 0 52px; margin: 0 0 52px; border-bottom: 1px solid var(--line); }
.prose > section:last-child { margin-bottom: 0; }
.step-label { display: inline-block; margin-bottom: 10px; color: var(--red); font-size: 11px; font-weight: 900; }
.prose h2 { margin-bottom: 16px; font-size: 28px; }
.prose p { color: #444b50; font-size: 16px; }
.prose a:not(.button) { color: var(--jade); text-decoration: underline; text-underline-offset: 3px; }
.check-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }
.check-row span, .check-row b { padding: 7px 10px; border: 1px solid var(--line); font-size: 12px; }
.check-row span { color: #fff; background: var(--ink); }
.check-row b { background: var(--white); }
.inline-download { margin-top: 8px; }
.callout { margin-top: 24px; padding: 18px 20px; border-left: 4px solid var(--yellow); background: #fff8df; }
.callout b { font-size: 13px; }
.callout p { margin: 4px 0 0; font-size: 14px; }
.article-figure { display: grid; grid-template-columns: 190px 1fr; align-items: center; gap: 22px; margin: 28px 0 0; padding: 18px; background: #eaf0ed; }
.article-figure img { width: 180px; height: auto; max-width: 400px; border: 1px solid var(--line); }
.article-figure figcaption { color: var(--muted); font-size: 13px; }

.faq-hero .page-index { background: #eef1fb; }
.faq-section { padding: 62px 0 86px; }
.faq-layout { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; display: grid; grid-template-columns: 250px 1fr; gap: 60px; }
.faq-tools { position: sticky; top: 104px; align-self: start; }
.faq-tools > label { display: block; margin-bottom: 8px; font-size: 13px; font-weight: 900; }
.search-box { display: flex; align-items: center; border: 1px solid var(--ink); background: var(--white); }
.search-box span { padding-left: 12px; font-size: 20px; }
.search-box input { width: 100%; min-width: 0; padding: 11px; border: 0; outline: 0; background: transparent; font-size: 13px; }
.topic-list { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; margin-top: 12px; }
.topic { min-height: 38px; border: 1px solid var(--line); background: transparent; color: var(--muted); cursor: pointer; }
.topic.active, .topic:hover { border-color: var(--jade); color: #fff; background: var(--jade); }
.faq-count { margin-top: 14px; color: var(--muted); font-size: 12px; }
.faq-list { border-top: 1px solid var(--ink); }
.faq-list details { border-bottom: 1px solid var(--line); background: transparent; }
.faq-list details[hidden] { display: none; }
.faq-list summary { min-height: 72px; display: grid; grid-template-columns: 52px 1fr 24px; align-items: center; padding: 10px 6px; cursor: pointer; font-weight: 800; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary > span { color: var(--red); font-size: 11px; }
.faq-list summary i { position: relative; width: 18px; height: 18px; }
.faq-list summary i::before, .faq-list summary i::after { content: ""; position: absolute; left: 2px; right: 2px; top: 8px; height: 2px; background: var(--jade); }
.faq-list summary i::after { transform: rotate(90deg); transition: transform .2s ease; }
.faq-list details[open] summary i::after { transform: rotate(0); }
.faq-list details > div { padding: 0 54px 20px; }
.faq-list details p { margin: 0; color: var(--muted); }
.faq-empty { padding: 32px 12px; color: var(--muted); text-align: center; }
.support-note { padding: 44px 0; border-top: 1px solid var(--line); background: #edf2ef; }
.support-note .section-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.support-note span { color: var(--blue); font-size: 11px; font-weight: 900; }
.support-note h2 { margin: 5px 0; font-size: 26px; }
.support-note p { margin: 0; color: var(--muted); }

@media (max-width: 900px) {
  .hero-inner { grid-template-columns: minmax(0, 1fr) minmax(300px, .72fr); gap: 28px; }
  .hero h1 { font-size: 42px; }
  .hero-shot img { width: 220px; }
  .feature-grid { grid-template-columns: 1fr 1fr; }
  .route-layout, .notes-layout { grid-template-columns: 210px 1fr; gap: 36px; }
  .gallery-card img { height: 370px; }
  .image-mat { height: 392px; }
  .article-layout { grid-template-columns: 190px minmax(0, 1fr); gap: 44px; }
  .faq-layout { grid-template-columns: 220px 1fr; gap: 36px; }
}

@media (max-width: 720px) {
  :root { --header: 64px; }
  .header-inner, .hero-inner, .section-inner, .page-hero-inner, .article-layout, .faq-layout { width: min(calc(100% - 32px), var(--max)); }
  .brand img { width: 38px; height: 38px; }
  .menu-toggle { display: block; }
  .menu-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .menu-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
  .menu-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
  .site-nav { position: fixed; left: 0; right: 0; top: var(--header); bottom: 0; display: flex; flex-direction: column; align-items: stretch; gap: 0; padding: 16px; background: var(--paper); transform: translateX(100%); visibility: hidden; transition: transform .22s ease, visibility .22s ease; }
  .site-nav.open { transform: translateX(0); visibility: visible; }
  .site-nav a { min-height: 54px; border-bottom: 1px solid var(--line); }
  .site-nav .nav-download { justify-content: center; margin: 18px 0 0; border: 0; }
  .hero { background: linear-gradient(180deg, #f7f8f5 0 64%, #eef1ed 64% 100%); }
  .hero-inner { min-height: 0; grid-template-columns: 1fr; gap: 14px; padding: 24px 0 26px; }
  .eyebrow { margin-bottom: 10px; }
  .hero h1 { margin-bottom: 12px; font-size: 34px; }
  .hero-copy > p { margin-bottom: 16px; font-size: 14px; line-height: 1.55; }
  .hero-actions { margin-bottom: 14px; }
  .button { min-height: 42px; padding: 8px 16px; }
  .hero-facts { display: none; }
  .hero-media { min-height: 292px; grid-template-columns: 34px 1fr; order: 2; overflow: visible; }
  .hero-shot { padding: 7px; box-shadow: 8px 8px 0 var(--blue); }
  .hero-shot img { width: 142px; }
  .spine-rail { max-height: 268px; }
  .edge-note { right: 4px; bottom: 18px; }
  .section { padding: 54px 0; }
  .section-heading { display: block; margin-bottom: 24px; }
  .section-heading > span { display: block; }
  .section-heading h2 { margin-top: 7px; font-size: 26px; }
  .feature-grid { grid-template-columns: 1fr; }
  .feature-item { min-height: 0; padding: 20px; }
  .feature-no { margin-bottom: 18px; }
  .route-layout, .notes-layout { display: block; }
  .route-layout .section-heading, .notes-layout .section-heading { margin-bottom: 24px; border-bottom: 1px solid var(--ink); }
  .route-list li { grid-template-columns: 42px 1fr; gap: 10px; }
  .text-link { display: inline-block; margin-top: 24px; }
  .gallery-grid { grid-template-columns: 1fr; gap: 28px; }
  .image-mat { height: 380px; }
  .gallery-card img { height: 360px; }
  .gallery-card figcaption { grid-template-columns: 100px 1fr; }
  .notes-board { grid-template-columns: 1fr; }
  .notes-board div { border-left: 1px solid var(--line); }
  .faq-preview-grid a { grid-template-columns: 44px 1fr 22px; min-height: 74px; }
  .faq-preview-grid b { font-size: 14px; }
  .download-inner, .support-note .section-inner { align-items: flex-start; flex-direction: column; }
  .download-inner h2 { font-size: 24px; }
  .footer-inner { flex-direction: column; gap: 20px; }
  .footer-inner nav { flex-wrap: wrap; justify-content: center; gap: 16px; }
  .page-hero-inner { min-height: 0; grid-template-columns: 1fr; gap: 24px; padding: 38px 0; }
  .page-hero h1 { font-size: 32px; }
  .page-hero h1.balanced-title span { display: block; white-space: nowrap; }
  .page-index { width: 150px; height: 100px; justify-self: start; }
  .page-index b { font-size: 36px; }
  .article-section, .faq-section { padding: 44px 0 62px; }
  .article-layout, .faq-layout { display: block; }
  .article-nav, .faq-tools { position: static; margin-bottom: 42px; }
  .prose > section { padding-bottom: 38px; margin-bottom: 38px; }
  .prose h2 { font-size: 24px; }
  .article-figure { grid-template-columns: 120px 1fr; }
  .article-figure img { width: 112px; }
  .faq-list summary { grid-template-columns: 40px 1fr 22px; min-height: 66px; font-size: 14px; }
  .faq-list details > div { padding: 0 28px 18px 40px; font-size: 14px; }
}

@media (max-width: 390px) {
  .hero h1 { font-size: 31px; }
  .hero-actions { gap: 8px; }
  .hero-actions .button { padding-inline: 13px; font-size: 14px; }
  .edge-note { right: 0; }
  .article-figure { display: block; }
  .article-figure img { width: 150px; margin: 0 auto 16px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; }
}