:root {
  --black: #000;
  --white: #fff;
  --gray: #b8b8b8;
  --muted: #777;
  --line: rgba(255, 255, 255, 0.25);
  --line-soft: rgba(255, 255, 255, 0.13);
  --header-h: 82px;
  --shell: min(1420px, calc(100vw - 112px));
  --ease: cubic-bezier(0.2, 0.75, 0.25, 1);
}

* { box-sizing: border-box; }
html { scrollbar-width: none; -ms-overflow-style: none; scroll-behavior: smooth; scroll-padding-top: 0; background: var(--black); }
html::-webkit-scrollbar, body::-webkit-scrollbar { display: none; width: 0; height: 0; }
body { margin: 0; overflow-x: hidden; color: var(--white); background: var(--black); font-family: Arial, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif; line-height: 1.5; -webkit-font-smoothing: antialiased; }
body.menu-open { overflow: hidden; }
a { color: inherit; text-decoration: none; }
button { color: inherit; font: inherit; }
img { display: block; max-width: 100%; }
h1, h2, h3, h4, p, dl, dd, ol, ul, address { margin: 0; }
.shell { width: var(--shell); margin: 0 auto; }

.skip-link { position: fixed; z-index: 200; top: 16px; left: 16px; padding: 12px 18px; color: var(--black); background: var(--white); transform: translateY(-180%); }
.skip-link:focus { transform: translateY(0); }

.site-header { position: fixed; z-index: 100; top: 0; right: 0; left: 0; color: var(--white); background: linear-gradient(to bottom, rgba(0,0,0,.82), transparent); border: 0; transition: background 300ms ease, box-shadow 300ms ease; }
.site-header.is-scrolled { background: rgba(3,8,15,.72); box-shadow: 0 10px 32px rgba(0,0,0,.22); -webkit-backdrop-filter: blur(18px) saturate(125%); backdrop-filter: blur(18px) saturate(125%); }
.header-inner { display: flex; min-height: var(--header-h); align-items: center; gap: 38px; }
.brand { display: inline-flex; width: 42px; flex: 0 0 auto; align-items: center; white-space: nowrap; }
.brand img { width: 42px; height: 42px; }
.main-nav { display: flex; align-items: center; gap: 34px; }
.main-nav a { position: relative; padding: 31px 0 27px; font-size: 12px; font-weight: 700; letter-spacing: .05em; text-transform: uppercase; }
.main-nav a::after { position: absolute; right: 100%; bottom: 22px; left: 0; height: 1px; content: ""; background: var(--white); transition: right 260ms var(--ease); }
.main-nav a:hover::after, .main-nav a:focus-visible::after, .main-nav a.is-active::after { right: 0; }
.language { display: flex; align-items: center; gap: 7px; margin-left: auto; font-size: 11px; }
.language button { padding: 5px 3px; color: var(--gray); background: transparent; border: 0; cursor: pointer; }
.language button[aria-pressed="true"] { color: var(--white); font-weight: 700; }
.menu-toggle { display: none; margin-left: auto; padding: 8px 0; background: transparent; border: 0; cursor: pointer; }
.menu-toggle__icon, .menu-toggle__icon::before, .menu-toggle__icon::after { display: block; width: 22px; height: 1px; background: currentColor; }
.menu-toggle__icon { position: relative; }
.menu-toggle__icon::before, .menu-toggle__icon::after { position: absolute; left: 0; content: ""; transition: transform 220ms ease, top 220ms ease; }
.menu-toggle__icon::before { top: -7px; }
.menu-toggle__icon::after { top: 7px; }
.menu-toggle[aria-expanded="true"] .menu-toggle__icon { background: transparent; }
.menu-toggle[aria-expanded="true"] .menu-toggle__icon::before { top: 0; transform: rotate(45deg); }
.menu-toggle[aria-expanded="true"] .menu-toggle__icon::after { top: 0; transform: rotate(-45deg); }

.hero, .section, .contact { position: relative; min-height: 100svh; overflow: hidden; isolation: isolate; }
.hero::before, .capabilities::before, .contact::before { position: absolute; z-index: -3; inset: 0; content: ""; background-position: center; background-size: cover; transform: scale(1.01); }
.hero::before, .contact::before { background-image: url("../assets/hero-city.jpg"); }
.capabilities::before { background-image: url("../assets/data-core.jpg"); }
.hero::after, .capabilities::after, .solutions::after, .contact::after { position: absolute; z-index: -2; inset: 0; content: ""; background: linear-gradient(90deg, rgba(0,0,0,.94) 0%, rgba(0,0,0,.57) 43%, rgba(0,0,0,.08) 76%), linear-gradient(0deg, rgba(0,0,0,.82) 0%, transparent 50%, rgba(0,0,0,.25) 100%); }
.hero-video { position: absolute; z-index: -3; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: center; background: var(--black); }
.hero-grid, .hero-orbit { display: none; }
.hero-inner { display: flex; min-height: 100svh; flex-direction: column; justify-content: flex-end; padding-top: 150px; padding-bottom: 92px; }
.hero-copy { display: grid; width: min(680px, 72vw); gap: 12px; }
.eyebrow { display: flex; align-items: center; color: var(--white); font-size: 13px; font-weight: 700; letter-spacing: .13em; text-transform: uppercase; }
.eyebrow > span:first-child { display: none; }
.hero h1 { max-width: 720px; font-size: clamp(46px, 4.7vw, 68px); font-weight: 800; line-height: 1; letter-spacing: -.04em; text-transform: uppercase; }
.hero h1 em { color: var(--white); font-style: normal; }
.hero-actions { display: flex; padding-top: 20px; }
.button { position: relative; z-index: 0; display: inline-flex; min-width: 160px; min-height: 54px; align-items: center; justify-content: center; gap: 24px; overflow: hidden; padding: 0 24px; color: var(--white); background: transparent; border: 1px solid rgba(255,255,255,.72); font-size: 12px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; transition: color 260ms ease; }
.button::before { position: absolute; z-index: -1; right: 0; bottom: 0; left: 0; height: 0; content: ""; background: var(--white); transition: height 260ms var(--ease); }
.button:hover, .button:focus-visible { color: var(--black); }
.button:hover::before, .button:focus-visible::before { height: 100%; }
.button--primary, .button--ghost { color: var(--white); background: transparent; border-color: rgba(255,255,255,.72); box-shadow: none; }
.scroll-cue { position: absolute; z-index: 2; right: 50%; bottom: 28px; width: 22px; height: 30px; transform: translateX(50%); }
.scroll-cue::before, .scroll-cue::after { position: absolute; bottom: 8px; width: 13px; height: 1px; content: ""; background: var(--white); }
.scroll-cue::before { left: 0; transform: rotate(45deg); }
.scroll-cue::after { right: 0; transform: rotate(-45deg); }
.scroll-cue span { display: none; }

.section { display: flex; align-items: flex-end; padding: 132px 0 82px; background: var(--black); }
.section-heading { display: grid; gap: 18px; }
.section-heading h2, .contact h2 { max-width: 840px; font-size: clamp(44px, 4.4vw, 64px); font-weight: 800; line-height: 1; letter-spacing: -.04em; text-transform: uppercase; }
.section-heading > p:last-child { max-width: 620px; color: var(--gray); font-size: 15px; }
.section-heading--center { align-items: start; text-align: left; }

.about::before { position: absolute; z-index: 0; right: -16vw; width: 62vw; aspect-ratio: 1; content: ""; border: 1px solid var(--line-soft); border-radius: 50%; box-shadow: 0 0 0 7vw rgba(255,255,255,.018), 0 0 0 14vw rgba(255,255,255,.012); }
.about-layout { position: relative; z-index: 1; display: grid; grid-template-columns: 1.05fr .95fr; gap: 100px; align-items: center; }
.about-story { display: grid; gap: 26px; }
.about-story .lead { max-width: 600px; color: var(--white); font-size: 22px; line-height: 1.48; }
.about-story > p:not(.lead) { color: var(--gray); }
.principles { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.principles article { display: grid; min-height: 146px; align-content: space-between; padding: 20px 0; gap: 12px; border-top: 1px solid var(--line); }
.principles article > span { color: var(--muted); font-size: 12px; }
.principles h3 { font-size: 18px; text-transform: uppercase; }
.principles p { color: var(--gray); font-size: 13px; }

.capabilities { align-items: flex-end; }
.capabilities > .shell { display: grid; gap: 50px; }
.capabilities .section-heading { max-width: 780px; }
.capability-path { display: grid; grid-template-columns: repeat(4,1fr); grid-column: 1/-1; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.capability-path li { display: grid; min-height: 194px; align-content: start; padding: 22px 24px 22px 0; gap: 11px; border-right: 1px solid var(--line-soft); }
.capability-path li + li { padding-left: 24px; }
.capability-path li:last-child { border-right: 0; }
.step-index { color: var(--muted); font-size: 11px; }
.step-icon { display: none; }
.capability-path h3 { padding-top: 23px; font-size: 17px; text-transform: uppercase; }
.capability-path p { color: var(--gray); font-size: 12px; }

.solutions { align-items: flex-end; }
.solution-backdrops { position: absolute; z-index: -3; inset: 0; overflow: hidden; background: var(--black); }
.solution-backdrop { position: absolute; inset: 0; opacity: 0; background-position: center; background-size: cover; transform: scale(1.015); transition: opacity 800ms ease, transform 6.5s linear; }
.solution-backdrop.is-active { opacity: 1; transform: scale(1.04); }
.solution-backdrop[data-sector-image="low-altitude"] { background-image: url("../assets/low-altitude.jpg"); }
.solution-backdrop[data-sector-image="digital-economy"] { background-image: url("../assets/digital-economy.jpg"); }
.solution-backdrop[data-sector-image="government"] { background-image: url("../assets/digital-government.jpg"); }
.solution-backdrop[data-sector-image="city"] { background-image: url("../assets/digital-city.jpg"); }
.solutions > .shell { position: relative; z-index: 1; display: grid; gap: 44px; }
.solutions .section-heading { max-width: 760px; }
.sector-tabs { display: grid; grid-template-columns: 180px minmax(0,780px); gap: 48px; align-items: end; }
.sector-nav { display: grid; align-content: end; gap: 16px; }
.tab-list { display: grid; border-left: 1px solid var(--line); }
.tab-list button { position: relative; padding: 12px 0 12px 20px; color: var(--muted); text-align: left; background: transparent; border: 0; cursor: pointer; font-size: 11px; font-weight: 700; letter-spacing: .05em; text-transform: uppercase; }
.tab-list button::before { position: absolute; top: 0; bottom: 0; left: -1px; width: 2px; content: ""; background: transparent; }
.tab-list button[aria-selected="true"] { color: var(--white); }
.tab-list button[aria-selected="true"]::before { background: var(--white); }
.carousel-toggle { display: inline-flex; width: max-content; align-items: center; gap: 8px; padding: 3px 0; color: var(--muted); background: transparent; border: 0; cursor: pointer; font-size: 9px; letter-spacing: .08em; }
.carousel-toggle:hover, .carousel-toggle:focus-visible { color: var(--white); }
.carousel-toggle__icon { position: relative; width: 10px; height: 10px; border-left: 2px solid currentColor; border-right: 2px solid currentColor; }
.carousel-toggle[aria-pressed="true"] .carousel-toggle__icon { border: 0; }
.carousel-toggle[aria-pressed="true"] .carousel-toggle__icon::before { position: absolute; inset: 0; content: ""; border-top: 5px solid transparent; border-bottom: 5px solid transparent; border-left: 8px solid currentColor; }
.carousel-progress { display: block; height: 1px; overflow: hidden; background: rgba(255,255,255,.18); }
.carousel-progress i { display: block; width: 100%; height: 100%; background: var(--white); transform: scaleX(0); transform-origin: left; }
.solutions.is-carousel-running .carousel-progress i { animation: sector-progress 6.5s linear forwards; }
@keyframes sector-progress { to { transform: scaleX(1); } }
[role="tabpanel"] { display: grid; grid-template-columns: 1fr 230px; gap: 36px; align-items: end; min-height: 240px; padding: 30px; background: rgba(0,0,0,.58); border: 1px solid var(--line); backdrop-filter: blur(14px); }
[role="tabpanel"][hidden] { display: none; }
.sector-copy { display: grid; gap: 14px; }
.sector-number { color: var(--muted); font-size: 11px; }
.sector-copy h3 { font-size: 28px; line-height: 1.08; text-transform: uppercase; }
.sector-copy > p:not(.sector-number) { max-width: 600px; color: var(--gray); font-size: 13px; }
.sector-copy ul { display: flex; flex-wrap: wrap; padding: 8px 0 0; gap: 8px 18px; list-style: none; }
.sector-copy li { color: #eee; font-size: 11px; }
.sector-copy li::before { content: "— "; color: var(--muted); }
.sector-visual { position: relative; display: flex; min-height: 160px; align-items: center; justify-content: center; gap: 12px; border: 1px solid var(--line-soft); }
.sector-visual span { font-size: 34px; font-weight: 700; }
.sector-visual i { width: 18px; height: 1px; background: var(--muted); }
.sector-visual p { position: absolute; right: 0; bottom: 12px; left: 0; color: var(--muted); text-align: center; font-size: 9px; letter-spacing: .12em; }

.cases { align-items: flex-end; background: radial-gradient(circle at 76% 45%, rgba(30,87,126,.24), transparent 30%), linear-gradient(135deg,#020508,#000 62%); }
.cases > .shell { display: grid; gap: 48px; }
.cases-heading { max-width: 820px; }
.case-grid { display: grid; grid-template-columns: repeat(3,1fr); border-top: 1px solid var(--line); }
.case-card { display: grid; min-height: 260px; align-content: start; padding: 28px 30px 30px 0; gap: 54px; border-right: 1px solid var(--line-soft); }
.case-card + .case-card { padding-left: 30px; }
.case-card:last-child { border-right: 0; }
.case-top { display: flex; align-items: center; justify-content: space-between; }
.case-index { color: var(--muted); font-size: 11px; }
.case-tag { color: var(--gray); font-size: 10px; letter-spacing: .08em; text-transform: uppercase; }
.case-card > div:nth-child(2) { display: grid; gap: 14px; }
.case-card h3 { font-size: 25px; line-height: 1.15; text-transform: uppercase; }
.case-card p { color: var(--gray); font-size: 12px; }

.contact { display: flex; min-height: 78svh; align-items: center; padding: 130px 0 80px; }
.contact::before { filter: grayscale(.35); }
.contact-layout { display: grid; grid-template-columns: .9fr 1.1fr; gap: 100px; align-items: end; }
.contact-copy { display: grid; gap: 22px; }
.contact-copy > p:not(.eyebrow) { max-width: 550px; color: var(--gray); }
.contact-copy .button { width: max-content; }
.contact-card { display: grid; grid-template-columns: 1fr auto; gap: 36px; padding: 30px; background: rgba(0,0,0,.64); border: 1px solid var(--line); backdrop-filter: blur(14px); }
.contact-details { display: grid; gap: 18px; }
.contact-details > div { display: grid; gap: 5px; padding-bottom: 18px; border-bottom: 1px solid var(--line-soft); }
.contact-details > div:last-child { padding-bottom: 0; border-bottom: 0; }
.contact-details span { color: var(--muted); font-size: 9px; letter-spacing: .1em; text-transform: uppercase; }
.contact-details strong, .contact-details a, .contact-details address { color: var(--white); font-size: 12px; font-style: normal; }
.qr { display: grid; align-content: center; justify-items: center; gap: 12px; }
.qr img { width: 116px; padding: 7px; background: var(--white); }
.qr span { color: var(--gray); font-size: 9px; }

.site-footer { color: var(--gray); background: var(--black); }
.footer-main { display: flex; align-items: center; gap: 36px; padding-top: 32px; padding-bottom: 26px; }
.brand--footer { color: var(--white); }
.footer-main p { margin-right: auto; font-size: 11px; }
.footer-main > a:last-child { font-size: 11px; }
.footer-legal { display: flex; align-items: center; justify-content: space-between; padding-top: 18px; padding-bottom: 24px; border-top: 1px solid var(--line-soft); font-size: 9px; }
.footer-legal div { display: flex; gap: 20px; }
.footer-legal a { display: inline-flex; align-items: center; gap: 6px; }
.floating-contact { display: none; }

.reveal { opacity: 1; transform: none; }
.is-reveal-ready .reveal { opacity: 0; transform: translateY(36px); transition: opacity 800ms var(--ease), transform 800ms var(--ease); }
.is-reveal-ready .reveal.is-visible { opacity: 1; transform: none; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--white); outline-offset: 4px; }

@media (max-width: 1180px) {
  :root { --shell: min(100% - 64px,1040px); }
  .header-inner { gap: 24px; }
  .main-nav { gap: 19px; }
  .main-nav a { font-size: 10px; }
  .sector-tabs { grid-template-columns: 150px 1fr; }
}

@media (max-width: 900px) {
  :root { --header-h: 70px; --shell: calc(100% - 42px); }
  .header-inner { min-height: var(--header-h); gap: 14px; }
  .brand { width: 36px; }
  .brand img { width: 36px; height: 36px; }
  .menu-toggle { display: flex; align-items: center; gap: 8px; }
  .menu-toggle__label { display: none; }
  .main-nav { position: fixed; z-index: 90; top: var(--header-h); right: 0; bottom: 0; left: 0; display: none; flex-direction: column; gap: 0; padding: 34px 22px; background: var(--black); }
  .main-nav.is-open { display: flex; }
  .main-nav a { width: 100%; padding: 18px 0; border-bottom: 1px solid var(--line-soft); font-size: 18px; }
  .main-nav a::after { display: none; }
  .language { margin-left: 0; }
  .hero-copy { width: min(100%,680px); }
  .about-layout, .contact-layout { grid-template-columns: 1fr; gap: 46px; }
  .about::before { top: 10%; right: -38vw; width: 90vw; }
  .capabilities, .solutions { min-height: auto; padding-top: 130px; padding-bottom: 75px; }
  .capabilities > .shell { grid-template-columns: 1fr; gap: 42px; }
  .capability-path { grid-template-columns: 1fr 1fr; }
  .capability-path li, .capability-path li + li { min-height: 175px; padding: 22px 20px 22px 0; border-bottom: 1px solid var(--line-soft); }
  .capability-path li:nth-child(even) { padding-left: 20px; border-right: 0; }
  .sector-tabs { grid-template-columns: 1fr; gap: 24px; }
  .sector-nav { gap: 12px; }
  .tab-list { display: flex; overflow-x: auto; border-bottom: 1px solid var(--line); border-left: 0; }
  .tab-list button { min-width: 120px; padding: 13px 12px; text-align: center; }
  .tab-list button::before { top: auto; right: 0; bottom: -1px; left: 0; width: auto; height: 2px; }
  .carousel-toggle { display: none; }
  .carousel-progress { width: 100%; }
  .cases { min-height: auto; }
  .case-grid { grid-template-columns: 1fr; }
  .case-card, .case-card + .case-card { min-height: 280px; padding: 28px 0; border-right: 0; border-bottom: 1px solid var(--line-soft); }
}

@media (max-width: 560px) {
  :root { --shell: calc(100% - 30px); }
  .language { gap: 3px; font-size: 9px; }
  .hero { min-height: 760px; }
  .hero::before, .contact::before { background-position: 64% center; }
  .hero h1 { font-size: 42px; }
  .button { width: 100%; }
  .hero-actions .button { width: 170px; }
  .section { min-height: auto; padding-top: 100px; padding-bottom: 70px; }
  .section-heading h2, .contact h2 { font-size: 39px; }
  .about { min-height: 760px; }
  .about-layout { gap: 34px; }
  .about-story .lead { font-size: 20px; }
  .principles { grid-template-columns: 1fr; }
  .principles article { min-height: 150px; }
  .capability-path { grid-template-columns: 1fr; }
  .capability-path li, .capability-path li + li, .capability-path li:nth-child(even) { min-height: auto; padding: 20px 0; border-right: 0; }
  .capability-path h3 { padding-top: 10px; }
  [role="tabpanel"] { grid-template-columns: 1fr; padding: 22px; }
  .sector-visual { min-height: 125px; }
  .solution-backdrop { background-position: 62% center; }
  .contact { min-height: auto; padding-top: 100px; padding-bottom: 60px; }
  .contact-card { grid-template-columns: 1fr; padding: 22px; }
  .qr { justify-items: start; }
  .footer-main, .footer-legal { align-items: flex-start; flex-direction: column; gap: 14px; }
  .footer-main p { margin-right: 0; }
  .footer-legal div { align-items: flex-start; flex-direction: column; gap: 8px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .hero-video { display: none; }
  *, *::before, *::after { animation-duration: 1ms; animation-iteration-count: 1; transition-duration: 1ms; }
  .is-reveal-ready .reveal { opacity: 1; transform: none; }
}