:root {
  --navy-950: #03142f;
  --navy-900: #06275b;
  --navy-800: #083a7a;
  --blue-600: #0768ed;
  --blue-500: #1686ff;
  --cyan-400: #37d7e6;
  --orange-500: #ff8a1f;
  --ink: #10213c;
  --muted: #63728a;
  --line: #dce5f2;
  --soft: #f4f8fd;
  --white: #ffffff;
  --container: 1180px;
  --shadow: 0 24px 70px rgba(4, 29, 71, 0.14);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
.container { width: min(calc(100% - 40px), var(--container)); margin-inline: auto; }
.skip-link { position: fixed; left: 12px; top: -80px; z-index: 100; padding: 10px 14px; background: #fff; border-radius: 8px; }
.skip-link:focus { top: 12px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  height: 78px;
  background: rgba(255,255,255,.94);
  border-bottom: 1px solid rgba(220,229,242,.9);
  backdrop-filter: blur(16px);
}
.header-inner { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand-mark {
  position: relative;
  width: 42px;
  height: 42px;
  border-radius: 13px;
  background: linear-gradient(145deg, var(--blue-600), #0344ae);
  box-shadow: 0 8px 20px rgba(7,104,237,.25);
}
.brand-mark::before,
.brand-mark::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  border: 3px solid #fff;
  border-bottom: 0;
  border-radius: 50% 50% 0 0;
}
.brand-mark::before { top: 10px; height: 12px; opacity: .72; }
.brand-mark::after { left: 15px; right: 15px; top: 17px; height: 7px; }
.brand-mark i { position: absolute; width: 6px; height: 6px; left: 18px; bottom: 8px; border-radius: 50%; background: var(--orange-500); }
.brand-copy { display: grid; line-height: 1.1; }
.brand-copy strong { font-size: 20px; letter-spacing: .04em; }
.brand-copy small { margin-top: 6px; color: #77849a; font-size: 12px; letter-spacing: .12em; }
.desktop-nav { display: flex; align-items: center; gap: 32px; color: #42516a; }
.desktop-nav a { position: relative; font-size: 15px; }
.desktop-nav a::after { content: ""; position: absolute; left: 0; right: 100%; bottom: -8px; height: 2px; background: var(--blue-600); transition: right .2s ease; }
.desktop-nav a:hover::after, .desktop-nav a:focus-visible::after { right: 0; }

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 52px;
  padding: 0 26px;
  border-radius: 12px;
  color: #fff;
  background: linear-gradient(135deg, var(--blue-600), #0752c5);
  box-shadow: 0 12px 28px rgba(7,104,237,.25);
  font-weight: 700;
  transition: transform .2s ease, box-shadow .2s ease;
}
.button:hover { transform: translateY(-2px); box-shadow: 0 16px 32px rgba(7,104,237,.32); }
.button:focus-visible, a:focus-visible { outline: 3px solid rgba(22,134,255,.35); outline-offset: 3px; }
.button-small { min-height: 42px; padding: 0 20px; font-size: 14px; }
.menu-toggle, .mobile-nav { display: none; }

.hero {
  position: relative;
  overflow: hidden;
  color: #fff;
  background:
    linear-gradient(110deg, rgba(3,20,47,.98) 0%, rgba(6,39,91,.97) 54%, rgba(5,60,119,.92) 100%);
}
.hero::before { content: ""; position: absolute; inset: 0; opacity: .08; background-image: linear-gradient(rgba(255,255,255,.24) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.24) 1px, transparent 1px); background-size: 56px 56px; mask-image: linear-gradient(to right, #000, transparent 78%); }
.hero-glow { position: absolute; width: 540px; height: 540px; right: 8%; top: -180px; border-radius: 50%; background: rgba(55,215,230,.18); filter: blur(20px); }
.hero-grid { position: relative; min-height: 650px; display: grid; grid-template-columns: 1.05fr .95fr; align-items: center; gap: 74px; padding-block: 74px; }
.hero-copy { max-width: 650px; }
.eyebrow { display: flex; align-items: center; gap: 10px; margin-bottom: 22px; color: #a9c9f7; font-size: 14px; font-weight: 700; letter-spacing: .15em; }
.eyebrow span { width: 30px; height: 2px; background: var(--cyan-400); }
h1 { margin: 0; font-size: clamp(44px, 5vw, 72px); line-height: 1.12; letter-spacing: -.04em; }
h1 em { color: #7ee8f0; font-style: normal; }
.hero-copy > p { max-width: 610px; margin: 26px 0 30px; color: #c5d4ea; font-size: 18px; line-height: 1.85; }
.hero-actions { display: flex; align-items: center; gap: 28px; }
.text-link { color: #fff; font-weight: 700; }
.text-link span { display: inline-block; margin-left: 5px; transition: transform .2s ease; }
.text-link:hover span { transform: translateX(4px); }
.hero-points { display: flex; padding: 0; margin: 48px 0 0; list-style: none; }
.hero-points li { display: grid; gap: 2px; padding: 0 26px; border-left: 1px solid rgba(255,255,255,.18); }
.hero-points li:first-child { padding-left: 0; border-left: 0; }
.hero-points b { font-size: 16px; }
.hero-points span { color: #90a9ca; font-size: 13px; }

.hero-visual { position: relative; min-height: 440px; border-radius: 28px; overflow: visible; }
.hero-image { width: 100%; height: 440px; display: block; object-fit: cover; object-position: 71% center; border-radius: 28px; border: 1px solid rgba(255,255,255,.18); box-shadow: 0 36px 80px rgba(0,0,0,.28); }
.hero-card { position: absolute; z-index: 2; left: -34px; bottom: 27px; width: 285px; padding: 22px; border: 1px solid rgba(255,255,255,.2); border-radius: 18px; background: rgba(4,30,70,.82); box-shadow: 0 24px 60px rgba(0,0,0,.3); backdrop-filter: blur(14px); }
.card-kicker { display: inline-block; margin-bottom: 8px; color: #7ee8f0; font-size: 12px; font-weight: 700; letter-spacing: .12em; }
.hero-card strong { display: block; font-size: 20px; line-height: 1.35; }
.hero-card p { margin: 8px 0 0; color: #afc4df; font-size: 13px; }
.carrier-row { display: flex; flex-wrap: wrap; gap: 9px; }
.carrier { display: inline-flex; align-items: center; gap: 7px; padding: 8px 11px; border: 1px solid rgba(255,255,255,.13); border-radius: 999px; color: #dbe7f7; background: rgba(255,255,255,.06); font-size: 12px; }
.carrier i, .dot { width: 7px; height: 7px; border-radius: 50%; }
.carrier.mobile i, .dot.mobile { background: #28b474; }
.carrier.unicom i, .dot.unicom { background: #ed4052; }
.carrier.telecom i, .dot.telecom { background: #3a91ff; }
.speed-badge { position: absolute; z-index: 3; right: -8px; top: 28px; display: grid; padding: 16px 20px; border-radius: 16px; color: var(--navy-950); background: #fff; box-shadow: var(--shadow); transform: rotate(2deg); }
.speed-badge span { color: #6d7c91; font-size: 12px; }
.speed-badge b { font-size: 19px; }

.trust-strip { border-bottom: 1px solid var(--line); background: #fff; }
.trust-inner { min-height: 90px; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.trust-inner > p { margin: 0; color: #8994a6; font-size: 14px; }
.trust-list { display: flex; flex-wrap: wrap; gap: 38px; font-weight: 700; }
.trust-list span { display: inline-flex; align-items: center; gap: 10px; }

.section { padding-block: 108px; }
.section-heading { display: grid; grid-template-columns: 1.15fr .85fr; align-items: end; gap: 80px; margin-bottom: 44px; }
.section-label { color: var(--blue-600); font-size: 14px; font-weight: 800; letter-spacing: .14em; }
h2 { margin: 10px 0 0; font-size: clamp(32px, 4vw, 48px); line-height: 1.25; letter-spacing: -.035em; }
.section-heading p { margin: 0; color: var(--muted); }
.service-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.service-card { position: relative; overflow: hidden; min-height: 310px; padding: 32px; border: 1px solid var(--line); border-radius: 20px; background: #fff; transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease; }
.service-card::before { content: ""; position: absolute; left: 0; right: 0; top: 0; height: 5px; }
.card-mobile::before { background: #28b474; }
.card-unicom::before { background: #ed4052; }
.card-telecom::before { background: #3a91ff; }
.service-card:hover { transform: translateY(-6px); border-color: #c4d4e8; box-shadow: var(--shadow); }
.service-number { color: #a4b2c5; font-size: 13px; font-weight: 800; letter-spacing: .15em; }
.service-card h3 { margin: 48px 0 13px; font-size: 27px; }
.service-card p { margin: 0 0 28px; color: var(--muted); }
.service-card a { position: absolute; left: 32px; bottom: 28px; color: var(--blue-600); font-size: 14px; font-weight: 800; }
.service-note { margin: 22px 0 0; color: #748198; font-size: 13px; text-align: right; }

.advantages { overflow: hidden; background: var(--soft); }
.advantage-layout { display: grid; grid-template-columns: .85fr 1.15fr; gap: 86px; align-items: start; }
.advantage-intro { position: sticky; top: 116px; }
.advantage-intro h2 { margin-bottom: 22px; }
.advantage-intro > p { max-width: 500px; margin: 0; color: var(--muted); font-size: 17px; }
.scene-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 32px; }
.scene-tags span { padding: 8px 13px; border: 1px solid #ccd9e9; border-radius: 999px; color: #34506f; background: rgba(255,255,255,.7); font-size: 13px; font-weight: 700; }
.advantage-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.advantage-card { min-height: 230px; padding: 29px; border: 1px solid #dce6f1; border-radius: 18px; background: #fff; }
.advantage-card:nth-child(even) { transform: translateY(34px); }
.advantage-card > span { display: inline-grid; width: 38px; height: 38px; place-items: center; border-radius: 10px; color: var(--blue-600); background: #eaf3ff; font-size: 12px; font-weight: 800; }
.advantage-card h3 { margin: 27px 0 9px; font-size: 22px; }
.advantage-card p { margin: 0; color: var(--muted); font-size: 15px; }

.process { background: #fff; }
.process-heading { align-items: center; }
.process-list { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; padding: 0; margin: 10px 0 0; list-style: none; counter-reset: steps; }
.process-list li { position: relative; min-height: 230px; padding: 28px 26px; border-top: 1px solid var(--line); }
.process-list li:not(:last-child)::after { content: "→"; position: absolute; right: -8px; top: 44px; z-index: 2; color: #9eb0c6; background: #fff; font-size: 20px; }
.step-number { width: 54px; height: 54px; display: grid; place-items: center; border-radius: 16px; color: #fff; background: var(--navy-900); box-shadow: 0 10px 22px rgba(6,39,91,.18); font-weight: 800; }
.process-list h3 { margin: 27px 0 8px; font-size: 21px; }
.process-list p { margin: 0; color: var(--muted); font-size: 15px; }

.coverage-section { padding: 0 0 108px; background: #fff; }
.coverage-panel { position: relative; overflow: hidden; display: grid; grid-template-columns: 1.15fr .85fr; gap: 72px; padding: 62px; border-radius: 28px; color: #fff; background: linear-gradient(125deg, #041a3d 0%, #073977 62%, #0569a8 100%); box-shadow: 0 32px 70px rgba(4,31,74,.18); }
.coverage-panel::after { content: ""; position: absolute; width: 470px; height: 470px; right: -180px; bottom: -280px; border-radius: 50%; border: 80px solid rgba(55,215,230,.1); }
.coverage-copy, .coverage-list { position: relative; z-index: 1; }
.section-label.light { color: #7ee8f0; }
.coverage-copy h2 { margin: 8px 0 17px; }
.coverage-copy p { max-width: 630px; margin: 0 0 30px; color: #bdd0e8; }
.button-light { color: var(--navy-900); background: #fff; box-shadow: none; }
.button-light:hover { box-shadow: 0 12px 28px rgba(0,0,0,.2); }
.coverage-list { padding: 27px; border: 1px solid rgba(255,255,255,.14); border-radius: 20px; background: rgba(255,255,255,.07); }
.coverage-list > span { color: #7ee8f0; font-size: 13px; font-weight: 800; letter-spacing: .12em; }
.coverage-list ul { display: grid; gap: 14px; padding: 0; margin: 22px 0; list-style: none; }
.coverage-list li { display: flex; align-items: center; gap: 13px; }
.coverage-list li i { width: 28px; height: 28px; display: grid; place-items: center; flex: 0 0 auto; border-radius: 8px; color: #03142f; background: #7ee8f0; font-size: 12px; font-style: normal; font-weight: 800; }
.coverage-list p { margin: 0; color: #9fb6d4; font-size: 12px; }

.faq { background: var(--soft); }
.faq-layout { display: grid; grid-template-columns: .75fr 1.25fr; gap: 85px; align-items: start; }
.faq-intro { position: sticky; top: 116px; }
.faq-intro h2 { margin-bottom: 20px; }
.faq-intro p { margin: 0; color: var(--muted); }
.faq-list { display: grid; gap: 12px; }
.faq-list details { border: 1px solid var(--line); border-radius: 16px; background: #fff; }
.faq-list summary { position: relative; padding: 23px 60px 23px 24px; cursor: pointer; list-style: none; font-size: 17px; font-weight: 800; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary span::before, .faq-list summary span::after { content: ""; position: absolute; right: 25px; top: 33px; width: 14px; height: 2px; background: var(--blue-600); transition: transform .2s ease; }
.faq-list summary span::after { transform: rotate(90deg); }
.faq-list details[open] summary span::after { transform: rotate(0); }
.faq-list details p { margin: 0; padding: 0 24px 23px; color: var(--muted); }

.contact { padding: 108px 0; color: #fff; background: var(--navy-950); }
.contact-panel { display: grid; grid-template-columns: .8fr 1.2fr; gap: 72px; align-items: end; }
.contact-copy h2 { margin: 8px 0 18px; }
.contact-copy p { margin: 0; color: #aabed9; }
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.contact-item { min-height: 180px; display: flex; flex-direction: column; padding: 23px; border: 1px solid rgba(255,255,255,.13); border-radius: 17px; background: rgba(255,255,255,.06); }
.contact-item > span { color: #8fa9ca; font-size: 13px; }
.contact-item strong { margin-top: 23px; font-size: 22px; }
.contact-item small { margin-top: auto; color: #8098b8; font-size: 12px; line-height: 1.55; }

.about { padding: 72px 0; border-bottom: 1px solid rgba(255,255,255,.08); color: #fff; background: #041a3b; }
.about-inner { display: grid; grid-template-columns: .9fr 1.1fr; gap: 80px; align-items: center; }
.about-title { display: flex; align-items: center; gap: 16px; }
.about-title h2 { margin: 0; font-size: 24px; letter-spacing: 0; }
.about-inner > p { margin: 0; color: #9fb4d0; }

.site-footer { padding: 42px 0 34px; color: #9bb0cb; background: #03142f; }
.footer-top { display: flex; align-items: center; justify-content: space-between; gap: 30px; padding-bottom: 28px; border-bottom: 1px solid rgba(255,255,255,.1); }
.footer-top div { display: flex; align-items: baseline; gap: 18px; }
.footer-top strong { color: #fff; font-size: 20px; }
.footer-top span, .footer-top a { font-size: 13px; }
.footer-top a { color: #d4e2f4; }
.footer-bottom { display: grid; grid-template-columns: .6fr 1.4fr; gap: 42px; padding-top: 25px; }
.footer-bottom p { margin: 0; font-size: 12px; line-height: 1.75; }

.reveal { opacity: 0; transform: translateY(14px); transition: opacity .6s ease, transform .6s ease; }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

@media (max-width: 900px) {
  .desktop-nav { display: none; }
  .header-inner > .button { margin-left: auto; }
  .menu-toggle { width: 42px; height: 42px; display: grid; place-content: center; gap: 5px; padding: 0; border: 1px solid var(--line); border-radius: 11px; background: #fff; }
  .menu-toggle span { width: 19px; height: 2px; display: block; border-radius: 2px; background: var(--navy-900); transition: transform .2s ease, opacity .2s ease; }
  .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); }
  .mobile-nav { position: absolute; left: 20px; right: 20px; top: 70px; display: grid; max-height: 0; overflow: hidden; border: 0 solid var(--line); border-radius: 14px; background: #fff; box-shadow: var(--shadow); opacity: 0; transform: translateY(-8px); transition: max-height .25s ease, opacity .2s ease, transform .2s ease, border-width .2s ease; }
  .mobile-nav.is-open { max-height: 360px; padding: 8px; border-width: 1px; opacity: 1; transform: translateY(0); }
  .mobile-nav a { padding: 13px 14px; border-radius: 9px; color: #314562; font-weight: 700; }
  .mobile-nav a:hover { background: var(--soft); }
  .hero-grid { min-height: auto; grid-template-columns: 1fr; gap: 44px; padding-block: 72px; }
  .hero-copy { max-width: 720px; }
  .hero-visual { min-height: 360px; }
  .hero-image { height: 400px; }
  .hero-card { left: 20px; }
  .section-heading { grid-template-columns: 1fr; gap: 18px; }
  .service-grid { grid-template-columns: 1fr; }
  .service-card { min-height: 260px; }
  .advantage-layout, .faq-layout, .contact-panel, .about-inner { grid-template-columns: 1fr; gap: 42px; }
  .advantage-intro, .faq-intro { position: static; }
  .process-list { grid-template-columns: 1fr 1fr; }
  .process-list li:not(:last-child)::after { display: none; }
  .coverage-panel { grid-template-columns: 1fr; gap: 42px; padding: 46px; }
  .contact-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-bottom { grid-template-columns: 1fr; gap: 12px; }
}

@media (max-width: 620px) {
  .container { width: min(calc(100% - 28px), var(--container)); }
  .site-header { height: 68px; }
  .brand-mark { width: 38px; height: 38px; }
  .brand-copy strong { font-size: 18px; }
  .brand-copy small { display: none; }
  .header-inner > .button { min-height: 38px; padding: 0 14px; }
  .header-inner > .button { display: none; }
  .hero-grid { padding-block: 58px; }
  h1 { font-size: clamp(40px, 12vw, 58px); }
  .hero-copy > p { font-size: 16px; }
  .hero-actions { align-items: flex-start; flex-direction: column; gap: 18px; }
  .hero-points { justify-content: space-between; margin-top: 38px; }
  .hero-points li { padding: 0 11px; }
  .hero-points b { font-size: 14px; }
  .hero-points span { font-size: 12px; }
  .hero-visual { min-height: 330px; }
  .hero-card { padding: 25px; }
  .hero-card strong { font-size: 23px; }
  .hero-image { height: 330px; object-position: 67% center; }
  .hero-card { left: 12px; bottom: 13px; width: 230px; padding: 16px; }
  .hero-card strong { font-size: 17px; }
  .speed-badge { right: 8px; top: 16px; padding: 12px 15px; }
  .speed-badge b { font-size: 16px; }
  .trust-inner { align-items: flex-start; flex-direction: column; padding-block: 22px; }
  .trust-list { gap: 14px 24px; }
  .section { padding-block: 78px; }
  .service-note { text-align: left; }
  .advantage-grid { grid-template-columns: 1fr; }
  .advantage-card:nth-child(even) { transform: none; }
  .advantage-card { min-height: auto; }
  .process-list { grid-template-columns: 1fr; }
  .process-list li { min-height: 0; display: grid; grid-template-columns: 54px 1fr; gap: 20px; padding-inline: 0; }
  .process-list h3 { margin-top: 0; }
  .coverage-section { padding-bottom: 78px; }
  .coverage-panel { width: 100%; border-radius: 0; padding: 54px 22px; }
  .contact { padding-block: 78px; }
  .contact-grid { grid-template-columns: 1fr; }
  .contact-item { min-height: 155px; }
  .about-title { align-items: flex-start; }
  .about-title h2 { font-size: 20px; }
  .footer-top, .footer-top div { align-items: flex-start; flex-direction: column; gap: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}