:root {
  --ink: #111315;
  --paper: #f7f8f6;
  --white: #ffffff;
  --line: #cbd0ce;
  --muted: #5d6662;
  --mint: #54e6a4;
  --mint-dark: #087346;
  --blue: #315bff;
  --blue-soft: #dce4ff;
  --yellow: #f2cf55;
  --header-h: 68px;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif;
  color: var(--ink);
  background: var(--paper);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); line-height: 1.7; }
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button { font: inherit; }
[id] { scroll-margin-top: 88px; }

.site-header { position: sticky; top: 0; z-index: 50; min-height: var(--header-h); background: rgba(247, 248, 246, .96); border-bottom: 1px solid var(--ink); }
.header-inner, .hero-inner, .section-inner, .page-hero-inner, .article-shell, .footer-inner { width: min(1180px, calc(100% - 48px)); margin-inline: auto; }
.header-inner { min-height: var(--header-h); display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 20px; font-weight: 800; }
.brand img { width: 38px; height: 38px; border: 1px solid var(--ink); border-radius: 50%; }
.site-nav { display: flex; align-items: center; gap: 28px; font-size: 14px; font-weight: 700; }
.site-nav > a:not(.download-link) { position: relative; padding: 21px 0 19px; }
.site-nav > a:not(.download-link)::after { content: ""; position: absolute; left: 0; right: 100%; bottom: 14px; height: 2px; background: var(--blue); transition: right .2s ease; }
.site-nav > a:hover::after, .site-nav > a.active::after { right: 0; }
.download-link { min-width: 98px; padding: 9px 16px; text-align: center; background: var(--mint); border: 1px solid var(--ink); box-shadow: 3px 3px 0 var(--ink); }
.menu-toggle { display: none; width: 42px; height: 42px; padding: 10px; border: 1px solid var(--ink); background: var(--white); }
.menu-toggle span { display: block; height: 2px; margin: 4px 0; background: var(--ink); }

.home-hero { border-bottom: 1px solid var(--ink); overflow: hidden; }
.hero-inner { min-height: 540px; display: grid; grid-template-columns: minmax(0, 1.02fr) minmax(440px, .98fr); gap: 62px; align-items: center; padding-block: 38px 28px; }
.hero-copy { min-width: 0; }
.eyebrow { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 16px; }
.eyebrow span { padding: 3px 9px; border: 1px solid var(--ink); font-size: 11px; font-weight: 800; letter-spacing: 0; }
.eyebrow span:first-child { background: var(--blue); color: var(--white); border-color: var(--blue); }
h1, h2, h3, p { margin-top: 0; }
.hero-copy h1 { max-width: 560px; margin-bottom: 14px; font-size: clamp(40px, 4.3vw, 64px); line-height: 1.12; letter-spacing: 0; }
.hero-copy > p { max-width: 590px; margin-bottom: 22px; color: #39413e; font-size: 16px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 24px; }
.button { min-width: 126px; min-height: 44px; display: inline-flex; align-items: center; justify-content: center; padding: 9px 20px; border: 1px solid var(--ink); font-weight: 800; }
.button-primary { background: var(--mint); box-shadow: 4px 4px 0 var(--ink); }
.button-secondary { background: var(--white); }
.button:hover { transform: translate(-1px, -1px); }
.mode-switch { display: flex; align-items: stretch; width: fit-content; max-width: 100%; border: 1px solid var(--ink); background: var(--white); overflow: auto; }
.mode-label, .mode-button { white-space: nowrap; padding: 7px 10px; border: 0; border-right: 1px solid var(--ink); font-size: 12px; font-weight: 700; }
.mode-label { background: var(--ink); color: var(--white); }
.mode-button { cursor: pointer; background: var(--white); color: var(--ink); }
.mode-button:last-child { border-right: 0; }
.mode-button.active { background: var(--blue-soft); color: #173bbd; }
.mode-readout { max-width: 540px; display: flex; gap: 12px; align-items: baseline; padding: 9px 12px; border-inline: 1px solid var(--line); border-bottom: 1px solid var(--line); font-size: 12px; color: var(--muted); }
.mode-readout strong { color: var(--ink); white-space: nowrap; }

.hero-media { position: relative; min-height: 450px; display: flex; justify-content: center; align-items: center; }
.media-index { position: absolute; top: 12px; right: 12px; display: flex; flex-direction: column; align-items: flex-end; font-size: 11px; font-weight: 800; }
.media-index span:first-child { font-size: 38px; line-height: 1; color: var(--blue); }
.phone-frame { position: relative; overflow: hidden; background: #dce2df; border: 2px solid var(--ink); border-radius: 24px; box-shadow: 10px 10px 0 var(--blue-soft); }
.phone-frame::before { content: ""; position: absolute; z-index: 2; top: 7px; left: 50%; width: 48px; height: 6px; transform: translateX(-50%); border-radius: 4px; background: rgba(17,19,21,.75); }
.main-phone { width: 224px; }
.main-phone img { width: 100%; max-width: 400px; height: auto; }
.preview-tab { position: absolute; z-index: 3; width: 116px; background: var(--white); border: 1px solid var(--ink); box-shadow: 5px 5px 0 var(--ink); overflow: hidden; }
.preview-tab span { display: block; padding: 4px 8px; background: var(--yellow); border-bottom: 1px solid var(--ink); font-size: 11px; font-weight: 800; }
.preview-tab img { width: 100%; max-width: 400px; height: 168px; object-fit: cover; object-position: top; }
.tab-filter { left: 6px; top: 96px; transform: rotate(-3deg); }
.tab-detail { right: 5px; bottom: 52px; transform: rotate(3deg); }
.spec-band { width: 100%; background: var(--ink); color: var(--white); }
.spec-band-inner { width: min(1180px, calc(100% - 48px)); margin-inline: auto; display: grid; grid-template-columns: repeat(4, 1fr); }
.spec-band-inner > div { min-width: 0; display: grid; grid-template-columns: 34px 1fr; padding: 12px 16px; border-right: 1px solid #454b48; }
.spec-band-inner > div:first-child { border-left: 1px solid #454b48; }
.spec-band-inner > div:last-child { border-right: 1px solid #454b48; }
.spec-band span { grid-row: 1 / 3; color: var(--mint); font-size: 12px; font-weight: 800; }
.spec-band strong { font-size: 13px; }
.spec-band small { color: #aeb7b3; font-size: 11px; }

.section { padding-block: 76px; border-bottom: 1px solid var(--ink); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 36px; margin-bottom: 34px; }
.section-no, .article-kicker { display: block; margin-bottom: 5px; color: var(--blue); font-size: 11px; font-weight: 800; letter-spacing: 0; }
.section h2, .final-cta h2, .page-hero h1, .article-content h2 { margin-bottom: 0; line-height: 1.2; letter-spacing: 0; }
.section h2, .final-cta h2 { font-size: clamp(28px, 3vw, 42px); }
.section-intro { max-width: 540px; color: var(--muted); font-size: 14px; }
.showcase-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 20px; }
.showcase-main, .showcase-side { min-width: 0; display: grid; align-items: center; border: 1px solid var(--ink); background: var(--white); }
.showcase-main { grid-template-columns: .86fr 1.14fr; }
.showcase-side { grid-template-rows: auto 1fr; }
.image-stage { min-height: 440px; display: flex; align-items: center; justify-content: center; padding: 22px; background: #e8ecea; overflow: hidden; }
.image-stage img { width: min(210px, 100%); max-width: 400px; border: 1px solid var(--ink); box-shadow: 7px 7px 0 var(--ink); }
.showcase-side .image-stage { min-height: 316px; }
.showcase-side .image-stage img { width: 160px; height: 284px; object-fit: cover; object-position: top; }
.caption { padding: 28px; }
.caption > span { color: var(--blue); font-size: 11px; font-weight: 800; }
.caption h3 { margin: 9px 0; font-size: 24px; line-height: 1.3; }
.caption p { margin-bottom: 0; color: var(--muted); font-size: 14px; }

.controls-section { background: var(--white); }
.controls-grid { display: grid; grid-template-columns: .74fr 1.26fr; gap: 74px; }
.controls-title { align-self: start; position: sticky; top: 100px; }
.controls-title .section-intro { margin: 18px 0 24px; }
.text-link { display: inline-flex; align-items: center; gap: 12px; color: #173bbd; font-size: 14px; font-weight: 800; }
.control-preview { width: 156px; position: relative; margin-top: 28px; border: 1px solid var(--ink); background: var(--white); }
.control-preview img { width: 100%; max-width: 400px; max-height: 230px; object-fit: cover; object-position: top; }
.control-preview span { display: block; padding: 5px 8px; border-top: 1px solid var(--ink); color: var(--blue); font-size: 10px; font-weight: 900; }
.control-list { border-top: 1px solid var(--ink); }
.control-list article { display: grid; grid-template-columns: 46px 1fr 66px; gap: 18px; align-items: start; padding: 24px 0; border-bottom: 1px solid var(--ink); }
.control-key { width: 34px; height: 34px; display: grid; place-items: center; background: var(--mint); border: 1px solid var(--ink); font-weight: 900; }
.control-list h3 { margin-bottom: 4px; font-size: 19px; }
.control-list p { margin-bottom: 0; color: var(--muted); font-size: 14px; }
.control-status { justify-self: end; padding: 3px 7px; background: var(--blue-soft); color: #173bbd; font-size: 10px; font-weight: 900; }

.features-section { background: #eef0ee; }
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); border: 1px solid var(--ink); background: var(--white); }
.feature-grid article { min-width: 0; min-height: 224px; padding: 24px; border-right: 1px solid var(--ink); }
.feature-grid article:last-child { border-right: 0; }
.feature-grid article > span { display: block; margin-bottom: 35px; color: var(--blue); font-size: 12px; font-weight: 900; }
.feature-grid h3 { margin-bottom: 8px; font-size: 18px; }
.feature-grid p { margin-bottom: 0; color: var(--muted); font-size: 13px; }

.routes-section h2 { margin-bottom: 28px; }
.route-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.route-grid a { position: relative; min-height: 180px; display: flex; flex-direction: column; align-items: flex-start; padding: 24px; border: 1px solid var(--ink); background: var(--white); transition: background .2s ease; }
.route-grid a:hover { background: var(--blue-soft); }
.route-grid span { color: var(--blue); font-size: 11px; font-weight: 900; }
.route-grid strong { margin: 20px 0 4px; font-size: 22px; }
.route-grid small { max-width: 410px; color: var(--muted); font-size: 13px; }
.route-grid b { position: absolute; right: 24px; top: 22px; font-size: 24px; }

.faq-preview { background: var(--white); }
.faq-list { border-top: 1px solid var(--ink); }
.faq-item { border-bottom: 1px solid var(--ink); }
.faq-item > button { width: 100%; min-height: 60px; display: flex; align-items: center; justify-content: space-between; gap: 18px; padding: 13px 4px; border: 0; background: transparent; color: var(--ink); text-align: left; cursor: pointer; font-weight: 800; }
.faq-item i { flex: 0 0 20px; width: 20px; height: 20px; position: relative; }
.faq-item i::before, .faq-item i::after { content: ""; position: absolute; inset: 9px 2px auto; height: 2px; background: var(--ink); transition: transform .2s ease; }
.faq-item i::after { transform: rotate(90deg); }
.faq-item > button[aria-expanded="true"] i::after { transform: rotate(0); }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height .25s ease; }
.faq-answer p { max-width: 850px; padding: 0 34px 18px 4px; margin-bottom: 0; color: var(--muted); font-size: 14px; }
.faq-item.open .faq-answer { max-height: 300px; }

.final-cta { padding-block: 48px; background: var(--blue); color: var(--white); border-bottom: 1px solid var(--ink); }
.cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.final-cta .section-no { color: #cbd6ff; }

.site-footer { padding-block: 38px; background: var(--ink); color: var(--white); }
.footer-inner { display: grid; justify-items: center; gap: 16px; text-align: center; }
.footer-brand { display: flex; align-items: center; gap: 9px; font-size: 18px; }
.footer-brand img { width: 34px; height: 34px; border-radius: 50%; }
.site-footer nav { display: flex; flex-wrap: wrap; justify-content: center; gap: 20px; font-size: 13px; }
.site-footer p { max-width: 720px; margin-bottom: 0; color: #b8c0bd; font-size: 12px; text-align: center; }
.site-footer small { color: #8d9692; text-align: center; }

.page-hero { padding-block: 58px; background: var(--white); border-bottom: 1px solid var(--ink); }
.page-hero-inner { display: grid; grid-template-columns: 1fr 290px; gap: 72px; align-items: end; }
.page-hero h1 { margin-bottom: 14px; font-size: clamp(38px, 4vw, 58px); }
.page-hero p { max-width: 730px; margin-bottom: 0; color: var(--muted); }
.page-hero-index { display: grid; grid-template-columns: 64px 1fr; padding: 18px; border: 1px solid var(--ink); background: var(--blue-soft); }
.page-hero-index > span { grid-row: 1 / 3; color: var(--blue); font-size: 42px; font-weight: 900; line-height: 1; }
.page-hero-index strong { font-size: 16px; }
.page-hero-index small { color: var(--muted); }
.faq-hero .page-hero-index { background: #dff9ec; }

.article-shell { display: grid; grid-template-columns: 240px 1fr; gap: 72px; padding-block: 64px 84px; }
.article-nav { position: sticky; top: 100px; align-self: start; display: grid; border: 1px solid var(--ink); background: var(--white); }
.article-nav > span { padding: 10px 14px; background: var(--ink); color: var(--white); font-size: 10px; font-weight: 900; }
.article-nav a { padding: 10px 14px; border-bottom: 1px solid var(--line); font-size: 13px; font-weight: 700; }
.article-nav a:last-child { border-bottom: 0; }
.article-nav a:hover { background: var(--blue-soft); }
.article-content { min-width: 0; }
.article-content > section { padding-bottom: 52px; margin-bottom: 52px; border-bottom: 1px solid var(--ink); }
.article-content h2 { margin-bottom: 18px; font-size: 30px; }
.article-content p { color: #3e4743; }
.article-content a:not(.button) { color: #173bbd; text-decoration: underline; text-underline-offset: 3px; }
.check-row { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 24px; border: 1px solid var(--ink); }
.check-row span { padding: 13px; border-right: 1px solid var(--ink); background: var(--white); text-align: center; font-size: 13px; font-weight: 800; }
.check-row span:last-child { border-right: 0; }
.notice { margin-top: 24px; padding: 20px; border-left: 5px solid var(--blue); background: var(--blue-soft); }
.notice p { margin: 5px 0 0; }
.guide-figure { width: min(520px, 100%); display: grid; grid-template-columns: 190px 1fr; align-items: center; gap: 24px; margin: 28px 0 0; padding: 22px; background: #e7ebe9; border: 1px solid var(--ink); }
.guide-figure img { width: 190px; max-width: 400px; border: 1px solid var(--ink); }
.guide-figure figcaption { font-size: 14px; color: var(--muted); }
.article-action { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 24px; border: 1px solid var(--ink); background: var(--white); }
.article-action > div { display: grid; }
.article-action span { color: var(--muted); font-size: 13px; }

.faq-page { padding-top: 64px; }
.faq-layout { display: grid; grid-template-columns: 260px 1fr; gap: 72px; align-items: start; }
.faq-sidebar { position: sticky; top: 100px; display: grid; }
.faq-sidebar h2 { margin-bottom: 22px; font-size: 30px; }
.faq-sidebar > a { padding: 10px 0; border-top: 1px solid var(--ink); font-size: 13px; font-weight: 800; }
.sidebar-note { margin-top: 28px; padding: 17px; background: var(--yellow); border: 1px solid var(--ink); }
.sidebar-note p { margin: 5px 0 0; font-size: 12px; }
.faq-groups { min-width: 0; }
.faq-groups > section { margin-bottom: 54px; }
.faq-group-title { display: flex; align-items: baseline; gap: 18px; margin-bottom: 18px; }
.faq-group-title > span { color: var(--blue); font-size: 13px; font-weight: 900; }
.faq-group-title h2 { font-size: 28px; }

@media (max-width: 920px) {
  .hero-inner { grid-template-columns: minmax(0, 1fr) 390px; gap: 24px; }
  .hero-copy h1 { font-size: 46px; }
  .preview-tab { width: 100px; }
  .tab-filter { left: 0; }
  .tab-detail { right: 0; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-grid article:nth-child(2) { border-right: 0; }
  .feature-grid article:nth-child(-n+2) { border-bottom: 1px solid var(--ink); }
  .article-shell, .faq-layout { grid-template-columns: 200px 1fr; gap: 40px; }
}

@media (max-width: 760px) {
  :root { --header-h: 62px; }
  .header-inner, .hero-inner, .section-inner, .page-hero-inner, .article-shell, .footer-inner { width: min(100% - 28px, 620px); }
  .site-header { min-height: var(--header-h); }
  .header-inner { min-height: var(--header-h); }
  .brand img { width: 34px; height: 34px; }
  .menu-toggle { display: block; }
  .site-nav { position: fixed; z-index: 70; top: 62px; left: 14px; right: 14px; display: none; padding: 10px; border: 1px solid var(--ink); background: var(--white); box-shadow: 5px 5px 0 var(--ink); }
  .site-nav.open { display: grid; }
  .site-nav > a:not(.download-link) { padding: 10px; border-bottom: 1px solid var(--line); }
  .site-nav > a:not(.download-link)::after { display: none; }
  .download-link { margin-top: 4px; box-shadow: none; }

  .hero-inner { min-height: 0; grid-template-columns: 1fr; gap: 12px; padding-block: 27px 18px; }
  .hero-copy h1 { max-width: 340px; margin-bottom: 10px; font-size: 39px; }
  .hero-copy > p { margin-bottom: 15px; font-size: 14px; line-height: 1.62; }
  .eyebrow { margin-bottom: 10px; }
  .hero-actions { margin-bottom: 16px; }
  .button { min-height: 41px; }
  .mode-switch { width: 100%; }
  .mode-switch .mode-label { display: none; }
  .mode-button { flex: 1; }
  .mode-readout { display: none; }
  .hero-media { min-height: 248px; overflow: hidden; }
  .main-phone { width: 145px; border-radius: 17px; box-shadow: 7px 7px 0 var(--blue-soft); }
  .preview-tab { width: 78px; box-shadow: 3px 3px 0 var(--ink); }
  .preview-tab img { height: 112px; }
  .tab-filter { left: calc(50% - 148px); top: 35px; }
  .tab-detail { right: calc(50% - 148px); bottom: 26px; }
  .media-index { top: 6px; right: 0; }
  .media-index span:first-child { font-size: 28px; }
  .spec-band-inner { width: min(100% - 28px, 620px); grid-template-columns: repeat(2, 1fr); }
  .spec-band-inner > div { padding: 9px 12px; border-bottom: 1px solid #454b48; }
  .spec-band-inner > div:nth-child(2) { border-right: 1px solid #454b48; }
  .spec-band-inner > div:nth-child(n+3) { border-bottom: 0; }

  .section { padding-block: 54px; }
  .section-heading { align-items: start; flex-direction: column; gap: 12px; margin-bottom: 25px; }
  .section h2, .final-cta h2 { font-size: 32px; }
  .showcase-grid, .showcase-main { grid-template-columns: 1fr; }
  .showcase-main .image-stage { order: 2; }
  .image-stage { min-height: 330px; }
  .showcase-side .image-stage { min-height: 280px; }
  .caption { padding: 22px; }
  .controls-grid { grid-template-columns: 1fr; gap: 28px; }
  .controls-title, .article-nav, .faq-sidebar { position: static; }
  .control-list article { grid-template-columns: 40px 1fr; }
  .control-status { grid-column: 2; grid-row: 2; justify-self: start; }
  .feature-grid { grid-template-columns: 1fr; }
  .feature-grid article { min-height: 0; border-right: 0; border-bottom: 1px solid var(--ink); }
  .feature-grid article:last-child { border-bottom: 0; }
  .feature-grid article > span { margin-bottom: 18px; }
  .route-grid { grid-template-columns: 1fr; }
  .cta-inner { align-items: flex-start; flex-direction: column; }

  .page-hero { padding-block: 40px; }
  .page-hero-inner { grid-template-columns: 1fr; gap: 25px; }
  .page-hero h1 { font-size: 39px; }
  .page-hero-index { max-width: 330px; }
  .article-shell, .faq-layout { grid-template-columns: 1fr; gap: 36px; padding-block: 45px 62px; }
  .article-nav { grid-template-columns: 1fr 1fr; }
  .article-nav > span { grid-column: 1 / -1; }
  .article-nav a { border-right: 1px solid var(--line); }
  .article-content > section { padding-bottom: 40px; margin-bottom: 40px; }
  .article-content h2 { font-size: 27px; }
  .check-row { grid-template-columns: 1fr; }
  .check-row span { border-right: 0; border-bottom: 1px solid var(--ink); }
  .check-row span:last-child { border-bottom: 0; }
  .guide-figure { grid-template-columns: 130px 1fr; }
  .guide-figure img { width: 130px; }
  .article-action { align-items: stretch; flex-direction: column; }
  .faq-page { padding-top: 48px; }
  .faq-sidebar > a { max-width: 380px; }
}

@media (max-width: 390px) {
  .header-inner, .hero-inner, .section-inner, .page-hero-inner, .article-shell, .footer-inner { width: calc(100% - 24px); }
  .hero-copy h1, .page-hero h1 { font-size: 36px; }
  .mode-button { padding-inline: 6px; font-size: 11px; }
  .hero-media { min-height: 232px; }
  .main-phone { width: 132px; }
  .tab-filter { left: 3px; }
  .tab-detail { right: 3px; }
  .spec-band small { display: none; }
  .spec-band-inner { width: calc(100% - 24px); }
  .spec-band-inner > div { grid-template-columns: 30px 1fr; }
  .guide-figure { grid-template-columns: 1fr; }
  .guide-figure img { width: 160px; justify-self: center; }
}

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