:root {
  --ink: #111214;
  --muted: #65676d;
  --paper: #f7f7f4;
  --white: #ffffff;
  --line: #d9dad8;
  --soft: #eceeec;
  --mint: #a7f0d2;
  --mint-strong: #27b982;
  --lilac: #c9b8ff;
  --lilac-strong: #8e66f2;
  --blue: #457cff;
  --shell: 76rem;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--paper); }
body { margin: 0; overflow-x: hidden; background: var(--paper); color: var(--ink); font-family: Arial, "Microsoft YaHei", "PingFang SC", sans-serif; font-size: 1rem; line-height: 1.65; letter-spacing: 0; }
body.menu-open { overflow: hidden; }
[hidden] { display: none !important; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button { font: inherit; color: inherit; }
.skip-link { position: fixed; z-index: 100; top: -5rem; left: 1rem; padding: .75rem 1rem; background: var(--ink); color: #fff; }
.skip-link:focus { top: 1rem; }
.section-shell { width: min(calc(100% - 2rem), var(--shell)); margin-inline: auto; }

.site-header { position: sticky; z-index: 50; top: 0; border-bottom: 1px solid rgba(17,18,20,.14); background: rgba(247,247,244,.92); backdrop-filter: blur(16px); }
.nav-shell { display: grid; grid-template-columns: 1fr auto; align-items: center; width: min(calc(100% - 2rem), var(--shell)); min-height: 4.25rem; margin-inline: auto; }
.brand { display: inline-flex; align-items: center; gap: .65rem; width: max-content; }
.brand > span:last-child { display: grid; line-height: 1; }
.brand b { font-size: 1rem; }
.brand small { margin-top: .25rem; color: var(--muted); font-size: .56rem; font-weight: 700; }
.brand-symbol { position: relative; display: inline-flex; align-items: flex-end; justify-content: center; gap: .16rem; width: 2.2rem; height: 2.2rem; padding: .42rem; border: 1px solid var(--ink); border-radius: 50%; background: var(--ink); transform: rotate(-8deg); }
.brand-symbol i { display: block; width: .23rem; border-radius: .15rem; background: var(--mint); }
.brand-symbol i:nth-child(1) { height: .55rem; }
.brand-symbol i:nth-child(2) { height: .92rem; background: var(--lilac); }
.brand-symbol i:nth-child(3) { height: 1.25rem; background: #fff; }
.desktop-nav, .nav-download { display: none; }
.menu-toggle { display: grid; place-items: center; width: 2.75rem; height: 2.75rem; border: 1px solid var(--ink); border-radius: 0; background: transparent; cursor: pointer; }
.menu-toggle svg { width: 1.15rem; }
.mobile-menu { position: absolute; top: 100%; left: 0; right: 0; display: grid; padding: .5rem 1rem 1rem; border-bottom: 1px solid var(--ink); background: var(--paper); }
.mobile-menu a { display: flex; align-items: center; min-height: 3rem; border-bottom: 1px solid var(--line); font-size: .9rem; font-weight: 700; }

.hero { position: relative; min-height: 46rem; overflow: hidden; padding: 5rem 1rem 3rem; background: #f2f3f1; }
.hero-meta { position: absolute; z-index: 4; top: 1.25rem; font-size: .58rem; font-weight: 800; }
.hero-meta-left { left: 1rem; }
.hero-meta-right { right: 1rem; text-align: right; }
.hero-band { position: absolute; z-index: 0; top: 9rem; left: -8%; width: 116%; height: 8rem; background: linear-gradient(90deg, rgba(201,184,255,.82), rgba(218,220,255,.7) 48%, rgba(167,240,210,.9)); transform: rotate(-2deg); }
.hero-product { position: relative; z-index: 2; width: min(100%, 44rem); margin: 0 auto; border: 1px solid rgba(17,18,20,.25); border-radius: .35rem; background: #fff; box-shadow: 0 2rem 4rem rgba(22,26,31,.16); transform: rotate(1.5deg); }
.window-bar { display: flex; align-items: center; gap: .7rem; min-height: 2rem; padding: .4rem .65rem; border-bottom: 1px solid var(--line); background: #fff; color: #5b5d62; font-size: .52rem; font-weight: 800; }
.window-bar > span { display: flex; gap: .25rem; }
.window-bar > span i { width: .45rem; height: .45rem; border-radius: 50%; background: #dadada; }
.window-bar > span i:first-child { background: var(--lilac); }
.window-bar > span i:nth-child(2) { background: var(--mint); }
.window-bar small { margin-left: auto; color: var(--mint-strong); font-size: .46rem; }
.hero-product > img { width: 100%; height: auto; }
.speed-chip { position: absolute; right: -.5rem; bottom: -2.2rem; display: grid; grid-template-columns: 1fr auto; align-items: baseline; min-width: 8.5rem; padding: .65rem .75rem; border: 1px solid var(--ink); background: var(--ink); color: #fff; box-shadow: .45rem .45rem 0 var(--mint); }
.speed-chip span { grid-column: 1 / -1; color: var(--mint); font-size: .47rem; font-weight: 800; }
.speed-chip strong { font-size: 1.55rem; line-height: 1; }
.speed-chip small { color: #c7c9cd; font-size: .5rem; }
.hero-copy { position: relative; z-index: 3; display: flex; flex-direction: column; width: min(100%, var(--shell)); margin: 2.8rem auto 0; }
.eyebrow { margin: 0 0 .75rem; color: #7b7d82; font-size: .6rem; font-weight: 800; }
.eyebrow.dark { color: #52545a; }
.hero h1 { margin: 0; font-size: 2.75rem; line-height: .98; font-weight: 500; }
.hero h1 span { display: block; font-weight: 400; }
.hero h1 strong { display: block; margin-top: .25rem; font-weight: 800; }
.hero-copy > p:not(.eyebrow) { max-width: 34rem; margin: 1.1rem 0 0; color: #55575c; font-size: .92rem; }
.hero-actions { display: flex; flex-direction: column; align-items: flex-start; gap: .8rem; margin-top: 1.4rem; }
.hero-copy .eyebrow { order: 0; }
.hero-copy h1 { order: 1; }
.hero-copy .hero-actions { order: 2; }
.hero-copy > p:not(.eyebrow) { order: 3; }
.primary-download { display: inline-flex; align-items: center; gap: .7rem; min-height: 3.75rem; padding: .55rem .75rem .55rem .55rem; border: 1px solid var(--ink); border-radius: .25rem; background: var(--ink); color: #fff; transition: transform .2s, box-shadow .2s; }
.primary-download:hover { transform: translateY(-2px); box-shadow: .4rem .4rem 0 var(--mint); }
.primary-download .button-icon { display: grid; place-items: center; width: 2.55rem; height: 2.55rem; background: var(--mint); color: var(--ink); }
.primary-download span:nth-child(2) { display: grid; min-width: 8.8rem; }
.primary-download b { font-size: .8rem; }
.primary-download small { color: #aeb0b5; font-size: .58rem; }
.primary-download svg { width: 1rem; }
.text-action { display: inline-flex; align-items: center; gap: .45rem; min-height: 2.75rem; padding: .25rem 0; border-bottom: 1px solid var(--ink); font-size: .75rem; font-weight: 700; }
.text-action svg { width: .95rem; }
.hero-index { position: absolute; right: 1rem; bottom: 1rem; color: #d0d1ce; font-size: 4rem; line-height: 1; font-weight: 800; }

.section-label { display: flex; align-items: center; gap: .6rem; margin-bottom: 1.5rem; color: #696b70; font-size: .55rem; font-weight: 800; }
.section-label span { display: grid; place-items: center; width: 1.8rem; height: 1.8rem; border: 1px solid currentColor; }
.section-label.light { color: #d2d4d0; }
.manifesto { padding-block: 5rem; }
.manifesto h2, .identity h2, .experience h2, .feature-lead h2, .install h2, .download-zone h2, .faq h2 { margin: 0; font-size: 2.25rem; line-height: 1.16; font-weight: 400; }
.manifesto h2 strong, .identity h2 strong, .experience h2 strong, .feature-lead h2 strong, .install h2 strong, .download-zone h2 strong, .faq h2 strong { font-weight: 800; }
.manifesto > p { max-width: 42rem; margin: 1.4rem 0 0 auto; color: var(--muted); font-size: .92rem; }

.identity { padding-block: 5rem; border-block: 1px solid var(--line); background: #fff; }
.identity-head { display: grid; gap: 1rem; }
.identity-note { max-width: 38rem; margin: 1rem 0 0; color: var(--muted); font-size: .82rem; }
.identity-grid { display: grid; gap: .75rem; margin-top: 2.5rem; }
.identity-visual { position: relative; min-height: 18rem; overflow: hidden; padding: 1rem; border: 1px solid var(--line); background: #efefed; }
.visual-caption { position: relative; z-index: 2; font-size: .52rem; font-weight: 800; }
.visual-speed { display: grid; place-items: center; background: #131416; color: #fff; }
.speed-rings { position: relative; display: grid; place-items: center; width: 12rem; height: 12rem; }
.speed-rings > i { position: absolute; inset: 0; border: 1px solid rgba(255,255,255,.35); border-radius: 50%; }
.speed-rings > i:nth-child(2) { inset: 1.4rem; border-color: var(--mint); }
.speed-rings > i:nth-child(3) { inset: 2.8rem; border: .7rem solid var(--lilac); border-left-color: transparent; transform: rotate(30deg); }
.speed-rings b { font-size: 2.5rem; }
.speed-rings small { position: absolute; bottom: 2.2rem; font-size: .42rem; }
.visual-speed .visual-caption { position: absolute; top: 1rem; left: 1rem; color: #c7c8cc; }
.visual-progress { display: flex; flex-direction: column; justify-content: space-between; background: linear-gradient(135deg, #e6ddff, #bdf5dc); }
.progress-art { margin: auto 0 1rem; }
.progress-art > b { display: block; font-size: 4.3rem; line-height: 1; }
.progress-art > span { display: block; height: .7rem; margin: 1rem 0 .7rem; border: 1px solid var(--ink); background: rgba(255,255,255,.45); }
.progress-art > span i { display: block; width: 94%; height: 100%; background: var(--ink); }
.progress-art small { font-size: .5rem; font-weight: 800; }
.visual-categories { display: flex; flex-direction: column; background: #f0f0ee; }
.category-lines { display: grid; gap: .55rem; margin-top: auto; }
.category-lines span { display: flex; justify-content: space-between; align-items: center; min-height: 3.2rem; padding: .7rem; border-top: 1px solid var(--ink); font-size: .65rem; font-weight: 800; }
.category-lines span:nth-child(2) { margin-left: 1.4rem; background: var(--lilac); }
.category-lines span:nth-child(3) { margin-left: 2.8rem; background: var(--mint); }
.category-lines b { font-size: 1.4rem; }
.palette-band { display: grid; grid-template-columns: 1fr auto auto auto; gap: .5rem; align-items: center; margin-top: .75rem; font-size: .48rem; font-weight: 800; }
.palette-band div { grid-column: 1 / -1; height: 4.5rem; background: linear-gradient(90deg, var(--lilac), #e2e2ff 48%, var(--mint)); }

.experience { padding-block: 5rem 0; background: #f1f2f0; }
.experience-heading { display: grid; gap: 1.2rem; }
.experience-heading > p { margin: 0; color: var(--muted); font-size: .88rem; }
.app-stage { position: relative; min-height: 33rem; margin-top: 3rem; padding: 4rem 1rem 7rem; overflow: hidden; background: #dedfdd; }
.app-stage::before { content: ""; position: absolute; inset: 0; opacity: .28; background-image: linear-gradient(#fff 1px, transparent 1px), linear-gradient(90deg, #fff 1px, transparent 1px); background-size: 2.5rem 2.5rem; }
.app-window { position: relative; z-index: 2; width: min(100%, 64rem); margin: 0 auto; border: 1px solid #aeb0ae; border-radius: .35rem; background: #fff; box-shadow: 0 2.2rem 4rem rgba(17,18,20,.2); }
.app-window img { width: 100%; }
.stage-note { position: absolute; z-index: 3; display: none; align-items: center; gap: .55rem; padding: .55rem .7rem; border: 1px solid var(--ink); background: #fff; font-size: .5rem; line-height: 1.25; }
.stage-note b { font-size: 1rem; }
.note-a { left: max(1rem, calc(50% - 34rem)); bottom: 2.5rem; }
.note-b { right: max(1rem, calc(50% - 34rem)); top: 2.5rem; background: var(--mint); }

.features { display: grid; gap: 2.5rem; padding-block: 5rem; }
.feature-lead > p:not(.eyebrow) { margin-top: 1rem; color: var(--muted); font-size: .9rem; }
.feature-story { display: grid; gap: .75rem; }
.feature-panel { position: relative; overflow: hidden; border: 1px solid var(--line); background: #fff; }
.panel-copy { padding: 1.25rem; }
.panel-copy > span { color: var(--muted); font-size: .5rem; font-weight: 800; }
.panel-copy h3 { margin: .35rem 0 .5rem; font-size: 1.25rem; }
.panel-copy p { margin: 0; color: var(--muted); font-size: .83rem; }
.panel-segments img { width: 100%; padding: 0 1rem 1rem; }
.panel-browser { background: #ededeb; }
.panel-browser img { width: 100%; }
.panel-resume { display: grid; min-height: 17rem; background: var(--ink); color: #fff; }
.panel-resume .panel-copy p { color: #b7b8bb; }
.panel-resume .panel-copy > span { color: var(--mint); }
.resume-mark { display: flex; align-items: center; gap: .7rem; padding: 1.25rem; color: var(--mint); }
.resume-mark svg { width: 3rem; height: 3rem; }
.resume-mark strong { font-size: 2rem; }

.install { padding-block: 5rem; background: var(--ink); color: #fff; }
.install-grid { display: grid; gap: 2rem; }
.install-copy > p:not(.eyebrow) { color: #b3b5b8; font-size: .9rem; }
.install-steps { list-style: none; margin: 0; padding: 0; border-top: 1px solid #45474b; }
.install-steps li { display: grid; grid-template-columns: 2rem 1fr 2rem; gap: .8rem; align-items: start; padding: 1.2rem 0; border-bottom: 1px solid #45474b; }
.install-steps li > span { color: var(--lilac); font-size: .65rem; font-weight: 800; }
.install-steps b { font-size: .95rem; }
.install-steps p { margin: .25rem 0 0; color: #9fa1a6; font-size: .78rem; }
.install-steps svg { width: 1.2rem; color: var(--mint); }

.download-zone { display: grid; gap: 2.5rem; padding-block: 5rem; }
.download-zone-copy > p:not(.eyebrow) { max-width: 34rem; color: var(--muted); font-size: .88rem; }
.download-ticket { border: 1px solid var(--ink); background: #fff; box-shadow: .7rem .7rem 0 var(--lilac); }
.ticket-top { display: grid; grid-template-columns: auto 1fr auto; gap: .8rem; align-items: center; padding: 1rem; border-bottom: 1px solid var(--ink); }
.brand-symbol.large { width: 2.8rem; height: 2.8rem; }
.ticket-top div { display: grid; }
.ticket-top small { color: var(--muted); font-size: .45rem; font-weight: 800; }
.ticket-top b { font-size: .9rem; }
.ticket-top > span:last-child { font-size: .6rem; font-weight: 800; }
.download-ticket dl { margin: 0; }
.download-ticket dl div { display: grid; grid-template-columns: 4.5rem 1fr; padding: .65rem 1rem; border-bottom: 1px solid var(--line); font-size: .68rem; }
.download-ticket dt { color: var(--muted); }
.download-ticket dd { margin: 0; font-weight: 700; }
.download-ticket dd i { display: inline-block; width: .45rem; height: .45rem; margin-right: .35rem; border-radius: 50%; background: var(--mint-strong); }
.ticket-download { display: flex; justify-content: space-between; align-items: center; min-height: 4rem; margin: 1rem; padding: .7rem .8rem; background: var(--ink); color: #fff; transition: background .2s; }
.ticket-download:hover { background: #343039; }
.ticket-download span { display: grid; }
.ticket-download small { color: var(--mint); font-size: .48rem; font-weight: 800; }
.ticket-download b { font-size: .85rem; }
.ticket-download svg { width: 1.2rem; }

.keyword-rail { display: flex; align-items: center; gap: 1rem; overflow: hidden; padding: .8rem 1rem; border-block: 1px solid var(--ink); background: var(--mint); white-space: nowrap; font-size: .63rem; font-weight: 800; }
.keyword-rail i { width: .4rem; height: .4rem; flex: 0 0 auto; border-radius: 50%; background: var(--lilac-strong); }

.faq { display: grid; gap: 2rem; padding-block: 5rem; }
.faq-list { border-top: 1px solid var(--ink); }
.faq details { border-bottom: 1px solid var(--ink); }
.faq summary { display: flex; justify-content: space-between; align-items: center; gap: 1rem; min-height: 4rem; cursor: pointer; list-style: none; font-size: .88rem; font-weight: 700; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary svg { width: 1rem; transition: transform .2s; }
.faq details[open] summary svg { transform: rotate(45deg); }
.faq details p { max-width: 38rem; margin: -.25rem 2rem 1.2rem 0; color: var(--muted); font-size: .82rem; }

footer { padding-top: 3rem; border-top: 1px solid var(--ink); background: #ececea; }
.footer-main { display: grid; gap: 1.2rem; }
.footer-main p { margin: 0; color: var(--muted); font-size: .72rem; }
.footer-main nav { display: flex; flex-wrap: wrap; gap: 1rem; font-size: .72rem; font-weight: 700; }
.footer-bottom { display: grid; gap: .35rem; margin-top: 2rem; padding-block: 1rem 5.5rem; border-top: 1px solid var(--line); color: #77797e; font-size: .62rem; }
.mobile-download { position: fixed; z-index: 45; left: 0; right: 0; bottom: 0; display: flex; justify-content: space-between; align-items: center; min-height: 4.25rem; padding: .55rem .75rem; border-top: 1px solid #404247; background: rgba(17,18,20,.96); color: #fff; backdrop-filter: blur(12px); }
.mobile-download > span { display: grid; }
.mobile-download b { font-size: .7rem; }
.mobile-download small { color: #9fa1a6; font-size: .55rem; }
.mobile-download a { display: inline-flex; align-items: center; gap: .4rem; min-height: 2.8rem; padding: .65rem .9rem; background: var(--mint); color: var(--ink); font-size: .75rem; font-weight: 800; }
.mobile-download svg { width: 1rem; }

@media (min-width: 48rem) {
  .section-shell { width: min(calc(100% - 3rem), var(--shell)); }
  .nav-shell { grid-template-columns: auto 1fr auto; gap: 2rem; width: min(calc(100% - 3rem), var(--shell)); min-height: 4.75rem; }
  .desktop-nav { display: flex; justify-content: center; gap: 2rem; font-size: .72rem; font-weight: 700; }
  .desktop-nav a { position: relative; }
  .desktop-nav a::after { content: ""; position: absolute; left: 0; right: 100%; bottom: -.25rem; height: 1px; background: var(--ink); transition: right .2s; }
  .desktop-nav a:hover::after { right: 0; }
  .nav-download { display: inline-flex; align-items: center; gap: .45rem; min-height: 2.8rem; padding: .55rem .85rem; border: 1px solid var(--ink); font-size: .7rem; font-weight: 800; }
  .nav-download:hover { background: var(--ink); color: #fff; }
  .nav-download svg { width: 1rem; }
  .menu-toggle, .mobile-menu { display: none !important; }
  .hero { min-height: 47rem; padding: 7rem 1.5rem 3rem; }
  .hero-meta { top: 1.5rem; }
  .hero-meta-left { left: 1.5rem; }
  .hero-meta-right { right: 1.5rem; }
  .hero-band { top: 12rem; height: 9rem; }
  .hero-product { width: min(56vw, 45rem); margin: 0 4vw 0 auto; }
  .hero-copy { margin-top: -13rem; }
  .hero h1 { max-width: 9ch; font-size: 4.4rem; }
  .hero-copy > p:not(.eyebrow) { max-width: 28rem; }
  .hero-copy > p:not(.eyebrow) { order: 2; }
  .hero-copy .hero-actions { order: 3; }
  .hero-actions { flex-direction: row; align-items: center; }
  .hero-index { right: 1.5rem; font-size: 6rem; }
  .manifesto { padding-block: 7rem; }
  .manifesto h2, .identity h2, .experience h2, .feature-lead h2, .install h2, .download-zone h2, .faq h2 { font-size: 3.2rem; }
  .manifesto > p { font-size: 1rem; }
  .identity { padding-block: 7rem; }
  .identity-head { grid-template-columns: .35fr 1fr; gap: 3rem; }
  .identity-grid { grid-template-columns: 1fr 1fr 1fr; }
  .identity-visual { min-height: 22rem; }
  .palette-band { grid-template-columns: 1fr auto auto auto; }
  .palette-band div { grid-column: auto; height: 5rem; }
  .experience { padding-top: 7rem; }
  .experience-heading { grid-template-columns: .3fr .9fr .6fr; gap: 3rem; align-items: end; }
  .experience-heading .section-label { align-self: start; }
  .app-stage { min-height: 44rem; padding: 5rem 2rem 8rem; }
  .stage-note { display: flex; }
  .features { grid-template-columns: .72fr 1.28fr; gap: 4rem; padding-block: 7rem; }
  .feature-lead { position: sticky; top: 7rem; align-self: start; }
  .feature-story { grid-template-columns: 1fr; }
  .panel-segments { grid-column: 1 / -1; display: grid; grid-template-columns: .6fr 1.4fr; align-items: center; }
  .panel-segments img { padding: 1rem; }
  .panel-browser { display: grid; grid-template-columns: 1.25fr .75fr; align-items: end; }
  .panel-resume { grid-template-columns: 1fr 1fr; align-items: center; min-height: 14rem; }
  .install { padding-block: 7rem; }
  .install-grid { grid-template-columns: .8fr 1.2fr; gap: 6rem; }
  .download-zone { grid-template-columns: 1fr 1fr; align-items: center; gap: 5rem; padding-block: 7rem; }
  .download-ticket { box-shadow: 1rem 1rem 0 var(--lilac); }
  .faq { grid-template-columns: .7fr 1.3fr; gap: 5rem; padding-block: 7rem; }
  .footer-main { grid-template-columns: auto 1fr auto; align-items: center; }
  .footer-main p { text-align: center; }
  .footer-bottom { grid-template-columns: 1fr auto; padding-bottom: 1rem; }
  .mobile-download { display: none; }
}

@media (min-width: 64rem) {
  .hero { min-height: 50rem; }
  .hero-product { width: min(56vw, 50rem); margin-right: max(2rem, calc((100vw - var(--shell)) / 2)); }
  .hero-copy { margin-top: -20rem; }
  .hero h1 { font-size: 4.7rem; }
  .hero-copy > p:not(.eyebrow) { font-size: 1rem; }
  .identity-visual { min-height: 25rem; }
  .progress-art > b { font-size: 5.5rem; }
}

@media (max-width: 22rem) {
  .hero { min-height: 51rem; }
  .hero h1 { font-size: 2.65rem; }
  .primary-download span:nth-child(2) { min-width: 7.5rem; }
  .manifesto h2, .identity h2, .experience h2, .feature-lead h2, .install h2, .download-zone h2, .faq h2 { font-size: 2rem; }
}

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