:root {
  --ink: #172028;
  --muted: #5b6670;
  --paper: #f5f3ed;
  --white: #ffffff;
  --line: #cdd2d0;
  --cyan: #16b8c7;
  --cyan-dark: #087985;
  --coral: #ff6b5f;
  --lime: #a6cf47;
  --header-h: 72px;
  --max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
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: 1.7; }
body.menu-open { overflow: hidden; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }

.site-header { height: var(--header-h); background: rgba(245, 243, 237, 0.96); border-bottom: 1px solid var(--ink); position: sticky; top: 0; z-index: 50; }
.header-inner, .hero-inner, .section-inner, .footer-inner { width: min(calc(100% - 48px), var(--max)); margin-inline: auto; }
.header-inner { height: 100%; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 19px; font-weight: 800; }
.brand img { width: 44px; height: 44px; }
.site-nav { display: flex; align-items: center; gap: 30px; font-size: 14px; font-weight: 700; }
.site-nav a { position: relative; padding: 8px 0; }
.site-nav a:not(.nav-download)::after { content: ""; position: absolute; left: 0; right: 100%; bottom: 3px; height: 2px; background: var(--cyan-dark); transition: right .2s ease; }
.site-nav a:hover::after, .site-nav a.active::after { right: 0; }
.site-nav .nav-download { padding: 9px 18px; color: var(--white); background: var(--ink); border: 1px solid var(--ink); }
.menu-toggle { display: none; width: 42px; height: 42px; padding: 10px; border: 1px solid var(--ink); background: transparent; cursor: pointer; }
.menu-toggle span { display: block; height: 2px; background: var(--ink); margin: 4px 0; }

.hero { border-bottom: 1px solid var(--ink); background: linear-gradient(90deg, rgba(22,184,199,.05) 1px, transparent 1px), linear-gradient(rgba(23,32,40,.045) 1px, transparent 1px); background-size: 30px 30px; }
.hero-inner { min-height: 646px; display: grid; grid-template-columns: 1.05fr .95fr; gap: 68px; align-items: center; padding-block: 44px; }
.hero-copy { min-width: 0; }
.eyebrow, .section-kicker, .block-code, .route-label { letter-spacing: 0; font-size: 12px; font-weight: 800; text-transform: uppercase; }
.eyebrow { display: flex; align-items: center; gap: 8px; color: var(--cyan-dark); }
.signal-dot { width: 9px; height: 9px; background: var(--cyan); border: 2px solid var(--ink); }
.hero h1 { max-width: 640px; margin: 19px 0 18px; font-size: clamp(42px, 4.5vw, 66px); line-height: 1.06; letter-spacing: 0; }
.hero h1 span { display: block; }
.hero-copy > p { max-width: 590px; margin: 0; color: #3d4851; font-size: 17px; line-height: 1.9; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }
.button { min-height: 46px; display: inline-flex; align-items: center; justify-content: center; padding: 10px 22px; border: 1px solid var(--ink); font-weight: 800; line-height: 1.4; transition: transform .15s ease, box-shadow .15s ease; }
.button:hover { transform: translate(-2px, -2px); box-shadow: 4px 4px 0 var(--ink); }
.button-primary { color: var(--white); background: var(--cyan-dark); }
.button-ghost { background: transparent; }
.button-light { background: var(--white); color: var(--ink); }
.hero-signals { display: flex; flex-wrap: wrap; gap: 18px; padding: 0; margin: 25px 0 0; list-style: none; font-size: 13px; font-weight: 700; }
.hero-signals li { display: flex; align-items: center; gap: 7px; }
.signal { width: 11px; height: 11px; border: 1px solid var(--ink); }
.cyan { background: var(--cyan); }.coral { background: var(--coral); }.lime { background: var(--lime); }

.hero-media { min-width: 0; height: 430px; position: relative; display: flex; align-items: center; justify-content: center; padding-top: 24px; border: 1px solid var(--ink); background: var(--white); box-shadow: 12px 12px 0 var(--cyan); overflow: hidden; }
.media-ruler { position: absolute; inset: 0 0 auto; height: 31px; display: flex; align-items: center; justify-content: space-around; border-bottom: 1px solid var(--line); color: var(--muted); font-size: 10px; font-weight: 800; }
.media-ruler span { width: 33.33%; text-align: center; border-right: 1px solid var(--line); }
.media-ruler span:last-child { border-right: 0; }
.phone-shot { margin: 0; position: absolute; display: flex; align-items: center; justify-content: center; }
.phone-shot img { width: 100%; height: 100%; max-width: 400px; object-fit: contain; background: #20252b; border: 4px solid var(--ink); box-shadow: 6px 6px 0 rgba(23,32,40,.18); }
.phone-shot-main { width: 168px; height: 370px; z-index: 3; left: 50%; top: 50%; transform: translate(-50%, -47%); }
.phone-shot-left, .phone-shot-right { width: 124px; height: 273px; z-index: 2; top: 50%; transform: translateY(-44%); }
.phone-shot-left { left: 7%; transform: translateY(-44%) rotate(-3deg); }
.phone-shot-right { right: 7%; transform: translateY(-44%) rotate(3deg); }

.section-inner { padding-block: 82px; }
.section-heading { margin-bottom: 34px; }
.section-heading h2, .download-inner h2, .guide-finish h2, .diagnostic-note h2, .faq-download h2 { margin: 7px 0 0; font-size: clamp(27px, 3vw, 40px); line-height: 1.22; letter-spacing: 0; }
.split-heading { display: flex; align-items: end; justify-content: space-between; gap: 40px; padding-bottom: 18px; border-bottom: 1px solid var(--ink); }
.section-note { max-width: 520px; color: var(--muted); font-size: 15px; }
.status-band { background: var(--white); border-bottom: 1px solid var(--ink); }
.status-band .section-inner { padding-block: 56px; }
.status-grid { display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--ink); }
.status-grid article { min-height: 176px; padding: 24px; border-right: 1px solid var(--ink); }
.status-grid article:last-child { border-right: 0; }
.status-index { color: var(--cyan-dark); font-size: 13px; font-weight: 900; }
.status-grid h3 { margin: 21px 0 7px; font-size: 20px; }
.status-grid p { margin: 0; color: var(--muted); font-size: 14px; }

.gallery-section { background: var(--paper); border-bottom: 1px solid var(--ink); }
.gallery-grid { display: grid; grid-template-columns: 1.12fr .94fr .94fr; gap: 18px; align-items: end; }
.gallery-item { margin: 0; }
.gallery-frame { height: 480px; display: flex; align-items: center; justify-content: center; padding: 26px; border: 1px solid var(--ink); background: var(--white); overflow: hidden; }
.gallery-item:nth-child(2) .gallery-frame { height: 420px; background: #d7f3f5; }
.gallery-item:nth-child(3) .gallery-frame { height: 385px; background: #eef5dc; }
.gallery-frame img { width: auto; height: 100%; max-width: 400px; object-fit: contain; border: 4px solid var(--ink); }
.gallery-item figcaption { display: grid; gap: 3px; padding-top: 12px; color: var(--muted); font-size: 13px; }
.gallery-item figcaption span { color: var(--ink); font-size: 16px; font-weight: 800; }

.feature-section { background: var(--white); border-bottom: 1px solid var(--ink); }
.feature-list { border-top: 1px solid var(--ink); }
.feature-list article { display: grid; grid-template-columns: 84px 1fr; gap: 24px; padding: 26px 0; border-bottom: 1px solid var(--line); }
.feature-code { color: var(--cyan-dark); font-size: 12px; font-weight: 900; }
.feature-list h3 { margin: 0 0 5px; font-size: 20px; }
.feature-list p { max-width: 750px; margin: 0; color: var(--muted); }

.routes-section { border-bottom: 1px solid var(--ink); }
.route-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.route-card { min-height: 270px; display: flex; flex-direction: column; align-items: flex-start; padding: 30px; border: 1px solid var(--ink); background: #d7f3f5; }
.route-card-dark { color: var(--white); background: var(--ink); }
.route-card h3 { margin: 40px 0 8px; font-size: 25px; line-height: 1.3; }
.route-card p { margin: 0; color: inherit; opacity: .8; }
.route-link { margin-top: auto; padding-top: 26px; font-weight: 800; border-bottom: 2px solid currentColor; }

.faq-preview { background: var(--white); border-bottom: 1px solid var(--ink); }
.text-link { font-weight: 800; color: var(--cyan-dark); border-bottom: 2px solid currentColor; }
.mini-faq { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.mini-faq article { padding: 24px; border: 1px solid var(--line); border-top: 5px solid var(--coral); }
.mini-faq article:nth-child(2) { border-top-color: var(--cyan); }
.mini-faq article:nth-child(3) { border-top-color: var(--lime); }
.mini-faq h3 { margin: 0 0 10px; font-size: 18px; line-height: 1.5; }
.mini-faq p { margin: 0; color: var(--muted); font-size: 14px; }

.download-band { color: var(--white); background: var(--cyan-dark); border-bottom: 1px solid var(--ink); }
.download-inner { min-height: 250px; display: flex; align-items: center; justify-content: space-between; gap: 40px; }
.download-note { margin-top: 8px; opacity: .82; }

.sub-hero { border-bottom: 1px solid var(--ink); background: var(--white); }
.sub-hero-inner { min-height: 380px; display: grid; grid-template-columns: 1fr .78fr; align-items: center; gap: 70px; }
.sub-hero h1 { margin: 11px 0 15px; font-size: clamp(38px, 4.3vw, 54px); line-height: 1.12; letter-spacing: 0; }
.sub-hero p { max-width: 670px; margin: 0; color: var(--muted); font-size: 16px; }
.guide-hero { background: linear-gradient(90deg, var(--white) 72%, #d7f3f5 72%); }
.faq-hero { background: linear-gradient(90deg, var(--white) 72%, #eef5dc 72%); }
.guide-map { min-height: 210px; display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: 8px; padding: 28px; border: 1px solid var(--ink); background: var(--paper); box-shadow: 9px 9px 0 var(--coral); }
.guide-map span { min-width: 62px; padding: 8px; text-align: center; border: 1px solid var(--ink); background: var(--white); font-weight: 800; }
.guide-map i { width: 16px; height: 1px; background: var(--ink); }

.guide-layout { display: grid; grid-template-columns: 210px minmax(0, 1fr); gap: 64px; align-items: start; }
.step-index { position: sticky; top: 100px; display: grid; border-top: 1px solid var(--ink); }
.step-index span { padding: 12px 0; color: var(--cyan-dark); font-size: 12px; font-weight: 900; }
.step-index a { padding: 11px 0; border-top: 1px solid var(--line); font-size: 14px; font-weight: 700; }
.guide-block { scroll-margin-top: 100px; padding: 0 0 64px; margin-bottom: 64px; border-bottom: 1px solid var(--ink); }
.guide-block h2 { margin: 6px 0 20px; font-size: clamp(25px, 3vw, 36px); line-height: 1.3; }
.guide-block p { color: #46515a; font-size: 16px; line-height: 2; }
.guide-block a { color: var(--cyan-dark); font-weight: 800; border-bottom: 1px solid currentColor; }
.check-strip { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 26px; border: 1px solid var(--ink); }
.check-strip span { padding: 13px; text-align: center; border-right: 1px solid var(--ink); font-size: 13px; font-weight: 800; }
.check-strip span:last-child { border-right: 0; }
.notice { margin-top: 24px; padding: 20px; border: 1px solid var(--ink); display: grid; gap: 5px; }
.notice-coral { background: #ffe1dd; }
.notice span { color: var(--muted); }
.guide-figure { display: grid; grid-template-columns: 180px 1fr; align-items: center; gap: 28px; margin: 30px 0 0; padding: 24px; background: #d7f3f5; border: 1px solid var(--ink); }
.guide-figure img { width: 180px; max-width: 400px; border: 3px solid var(--ink); }
.guide-figure figcaption { font-weight: 700; }
.guide-finish, .diagnostic-note, .faq-download { display: flex; align-items: center; justify-content: space-between; gap: 30px; padding: 30px; border: 1px solid var(--ink); background: #eef5dc; }
.guide-finish p, .diagnostic-note p, .faq-download p { margin: 8px 0 0; color: var(--muted); }

.diagnostic-board { display: grid; grid-template-columns: 1fr 1fr; border: 1px solid var(--ink); box-shadow: 9px 9px 0 var(--cyan); }
.diagnostic-board span { min-height: 90px; display: flex; align-items: center; justify-content: center; border-right: 1px solid var(--ink); border-bottom: 1px solid var(--ink); background: var(--white); font-size: 18px; font-weight: 900; }
.diagnostic-board span:nth-child(2n) { border-right: 0; }
.diagnostic-board span:nth-child(n+3) { border-bottom: 0; }
.diagnostic-board .cyan-bg { background: #d7f3f5; }.diagnostic-board .coral-bg { background: #ffe1dd; }.diagnostic-board .lime-bg { background: #eef5dc; }
.faq-toolbar { display: flex; justify-content: space-between; align-items: end; gap: 30px; padding-bottom: 24px; border-bottom: 1px solid var(--ink); }
.faq-toolbar h2 { margin: 6px 0 0; font-size: 38px; }
.faq-filters { display: flex; flex-wrap: wrap; gap: 8px; }
.filter-button { min-width: 64px; padding: 8px 13px; border: 1px solid var(--ink); background: transparent; cursor: pointer; font-weight: 700; }
.filter-button.active { color: var(--white); background: var(--ink); }
.faq-list { margin-top: 30px; border-top: 1px solid var(--ink); }
.faq-item { border-bottom: 1px solid var(--ink); }
.faq-item[hidden] { display: none; }
.faq-item > button { width: 100%; min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 14px 8px; border: 0; background: transparent; color: var(--ink); text-align: left; cursor: pointer; font-weight: 800; }
.faq-item > button span { display: flex; align-items: center; gap: 18px; }
.faq-item > button i { width: 34px; color: var(--cyan-dark); font-style: normal; font-size: 12px; }
.faq-item > button b { width: 32px; height: 32px; flex: 0 0 32px; display: grid; place-items: center; border: 1px solid var(--ink); font-size: 20px; line-height: 1; }
.faq-answer { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .25s ease; }
.faq-answer p { overflow: hidden; margin: 0; padding: 0 58px 0 60px; color: var(--muted); }
.faq-item.open .faq-answer { grid-template-rows: 1fr; }
.faq-item.open .faq-answer p { padding-bottom: 23px; }
.faq-item.open > button b { color: var(--white); background: var(--coral); }
.diagnostic-note { margin-top: 56px; background: #d7f3f5; }
.faq-download { margin-top: 20px; background: var(--white); }

.site-footer { background: var(--ink); color: var(--white); }
.footer-inner { min-height: 290px; display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; padding-block: 52px; }
.footer-brand { display: flex; align-items: center; gap: 9px; font-size: 18px; font-weight: 800; }
.footer-brand img { width: 36px; height: 36px; }
.site-footer nav { display: flex; flex-wrap: wrap; justify-content: center; gap: 24px; margin: 24px 0; font-size: 14px; }
.disclaimer { max-width: 760px; margin: 0; color: #c8d0d4; font-size: 13px; text-align: center; }
.copyright { margin: 13px 0 0; color: #89959d; font-size: 12px; text-align: center; }

@media (max-width: 900px) {
  :root { --header-h: 64px; }
  .header-inner, .hero-inner, .section-inner, .footer-inner { width: min(calc(100% - 32px), var(--max)); }
  .menu-toggle { display: block; }
  .site-nav { position: fixed; inset: var(--header-h) 0 auto; display: grid; gap: 0; padding: 12px 16px 20px; background: var(--paper); border-bottom: 1px solid var(--ink); transform: translateY(-130%); visibility: hidden; transition: transform .25s ease, visibility .25s ease; }
  .site-nav.open { transform: translateY(0); visibility: visible; }
  .site-nav a { padding: 13px 10px; border-bottom: 1px solid var(--line); }
  .site-nav .nav-download { margin-top: 10px; text-align: center; border-bottom: 1px solid var(--ink); }
  .hero-inner { min-height: 0; grid-template-columns: 1fr; gap: 26px; padding-block: 28px 36px; }
  .hero-media { height: 300px; max-width: 520px; width: 100%; margin-inline: auto; box-shadow: 8px 8px 0 var(--cyan); }
  .phone-shot-main { width: 118px; height: 260px; }
  .phone-shot-left, .phone-shot-right { width: 84px; height: 185px; }
  .phone-shot-left { left: 12%; }.phone-shot-right { right: 12%; }
  .status-grid, .mini-faq { grid-template-columns: 1fr; }
  .status-grid article { border-right: 0; border-bottom: 1px solid var(--ink); }
  .status-grid article:last-child { border-bottom: 0; }
  .gallery-grid { grid-template-columns: repeat(3, 1fr); }
  .gallery-frame, .gallery-item:nth-child(2) .gallery-frame, .gallery-item:nth-child(3) .gallery-frame { height: 360px; padding: 15px; }
  .sub-hero-inner { min-height: 340px; grid-template-columns: 1fr; gap: 28px; padding-block: 52px; }
  .guide-hero, .faq-hero { background: var(--white); }
  .guide-map, .diagnostic-board { max-width: 560px; width: 100%; }
  .guide-layout { grid-template-columns: 1fr; gap: 32px; }
  .step-index { position: static; grid-template-columns: repeat(5, 1fr); border: 1px solid var(--ink); }
  .step-index span { grid-column: 1 / -1; padding-inline: 12px; }
  .step-index a { padding: 10px; border-right: 1px solid var(--line); font-size: 12px; text-align: center; }
}

@media (max-width: 620px) {
  .header-inner, .hero-inner, .section-inner, .footer-inner { width: min(calc(100% - 24px), var(--max)); }
  .brand img { width: 38px; height: 38px; }
  .hero h1 { font-size: 34px; }
  .hero-copy > p { font-size: 15px; line-height: 1.75; }
  .hero-actions { display: grid; grid-template-columns: 1fr 1fr; }
  .button { padding-inline: 13px; font-size: 14px; }
  .hero-signals { gap: 9px 14px; margin-top: 18px; }
  .hero-media { height: 260px; }
  .phone-shot-main { width: 101px; height: 222px; }
  .phone-shot-left, .phone-shot-right { width: 70px; height: 154px; }
  .phone-shot-left { left: 8%; }.phone-shot-right { right: 8%; }
  .section-inner { padding-block: 60px; }
  .split-heading, .download-inner, .guide-finish, .diagnostic-note, .faq-download, .faq-toolbar { align-items: flex-start; flex-direction: column; gap: 18px; }
  .status-band .section-inner { padding-block: 48px; }
  .status-grid article { min-height: 0; }
  .gallery-grid { grid-template-columns: 1fr; gap: 34px; }
  .gallery-frame, .gallery-item:nth-child(2) .gallery-frame, .gallery-item:nth-child(3) .gallery-frame { height: 390px; }
  .feature-list article { grid-template-columns: 58px 1fr; gap: 14px; }
  .route-grid { grid-template-columns: 1fr; }
  .route-card { min-height: 240px; }
  .download-inner { min-height: 0; }
  .sub-hero-inner { min-height: 0; padding-block: 46px; }
  .sub-hero h1 { font-size: 34px; }
  .guide-map { min-height: 0; gap: 6px; padding: 18px 12px; }
  .guide-map span { min-width: 52px; font-size: 13px; }
  .guide-map i { width: 8px; }
  .step-index { grid-template-columns: 1fr 1fr; }
  .step-index a { border-bottom: 1px solid var(--line); }
  .check-strip { grid-template-columns: 1fr; }
  .check-strip span { border-right: 0; border-bottom: 1px solid var(--ink); }
  .check-strip span:last-child { border-bottom: 0; }
  .guide-figure { grid-template-columns: 1fr; justify-items: center; text-align: center; }
  .faq-toolbar h2 { font-size: 32px; }
  .faq-filters { width: 100%; display: grid; grid-template-columns: repeat(3, 1fr); }
  .faq-item > button { align-items: flex-start; min-height: 68px; padding-inline: 0; }
  .faq-item > button span { gap: 8px; }
  .faq-item > button i { width: 28px; flex: 0 0 28px; }
  .faq-answer p { padding-inline: 36px 6px; }
  .footer-inner { min-height: 260px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}