:root {
  --brand: #1769ff;
  --brand-2: #6d4aff;
  --brand-soft: #eaf2ff;
  --ink: #10203a;
  --muted: #61708a;
  --line: #e4eaf2;
  --surface: #f5f7fb;
  --white: #fff;
  --success: #16a879;
  --shadow: 0 16px 50px rgba(42, 71, 120, .10);
  --shadow-sm: 0 8px 28px rgba(42, 71, 120, .08);
  --radius: 22px;
  --radius-sm: 14px;
  --container: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: #fff;
  font-family: Inter, "HarmonyOS Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(circle at 8% 8%, rgba(92, 157, 255, .12), transparent 24rem),
    radial-gradient(circle at 92% 30%, rgba(118, 82, 255, .09), transparent 22rem);
}
a { color: inherit; text-decoration: none; }
img, svg { max-width: 100%; display: block; }
button, input, summary { font: inherit; }
.container { width: min(var(--container), calc(100% - 40px)); margin-inline: auto; }
.section { padding: 104px 0; position: relative; }
.section-soft { background: linear-gradient(180deg, rgba(245,248,252,.84), rgba(248,250,253,.52)); }
.section-head { max-width: 720px; margin: 0 auto 54px; text-align: center; }
.section-head.left { margin-left: 0; text-align: left; }
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--brand);
  font-weight: 750;
  font-size: 14px;
  letter-spacing: .04em;
  background: var(--brand-soft);
  border: 1px solid rgba(23,105,255,.12);
  border-radius: 999px;
  padding: 7px 12px;
}
.eyebrow::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--brand); box-shadow: 0 0 0 5px rgba(23,105,255,.10); }
h1, h2, h3, h4 { margin: 0 0 16px; color: #0c1b32; line-height: 1.22; letter-spacing: -.025em; }
h1 { font-size: clamp(42px, 6vw, 72px); font-weight: 850; }
h2 { font-size: clamp(32px, 4vw, 46px); font-weight: 820; }
h3 { font-size: 21px; font-weight: 760; }
p { margin: 0 0 18px; }
.lead { font-size: 19px; color: var(--muted); max-width: 690px; }
.gradient-text { background: linear-gradient(110deg, var(--brand), var(--brand-2)); color: transparent; background-clip: text; -webkit-background-clip: text; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 50px;
  padding: 0 22px;
  border-radius: 13px;
  font-weight: 760;
  border: 1px solid transparent;
  transition: transform .25s ease, box-shadow .25s ease, background .25s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { color: #fff; background: linear-gradient(120deg, var(--brand), var(--brand-2)); box-shadow: 0 12px 26px rgba(57, 92, 255, .24); }
.btn-primary:hover { box-shadow: 0 16px 34px rgba(57, 92, 255, .32); }
.btn-ghost { background: rgba(255,255,255,.78); border-color: var(--line); }
.btn-sm { min-height: 42px; padding: 0 17px; font-size: 14px; }
.icon { width: 20px; height: 20px; stroke: currentColor; fill: none; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,.83);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(224,231,240,.72);
}
.nav { min-height: 74px; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { display: flex; align-items: center; gap: 11px; font-size: 21px; font-weight: 850; white-space: nowrap; }
.brand-mark {
  width: 38px; height: 38px; border-radius: 12px; color: #fff;
  display: grid; place-items: center;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  box-shadow: 0 8px 20px rgba(23,105,255,.25);
}
.brand-mark svg { width: 23px; height: 23px; }
.nav-links { display: flex; align-items: center; gap: 28px; color: #46546c; font-size: 14px; font-weight: 650; }
.nav-links a { transition: color .2s; }
.nav-links a:hover { color: var(--brand); }
.nav-actions { display: flex; align-items: center; gap: 10px; }
.menu-btn { display: none; border: 0; background: transparent; padding: 8px; color: var(--ink); cursor: pointer; }

.hero { padding: 86px 0 82px; overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: 1.02fr .98fr; align-items: center; gap: 64px; }
.hero-copy .eyebrow { margin-bottom: 24px; }
.hero-copy .lead { margin: 24px 0 30px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.trust-line { margin-top: 30px; display: flex; flex-wrap: wrap; gap: 18px; color: var(--muted); font-size: 14px; }
.trust-line span { display: flex; align-items: center; gap: 7px; }
.trust-line svg { color: var(--success); }
.hero-visual { position: relative; min-height: 520px; display: grid; place-items: center; }
.hero-glow { position: absolute; width: 440px; height: 440px; border-radius: 50%; filter: blur(10px); background: radial-gradient(circle, rgba(43,119,255,.20), rgba(111,75,255,.05) 55%, transparent 72%); animation: breathe 5s ease-in-out infinite; }
.network-card {
  width: 100%; position: relative; z-index: 1;
  padding: 20px; border-radius: 30px;
  background: rgba(255,255,255,.82);
  border: 1px solid rgba(207,220,239,.9);
  box-shadow: 0 30px 80px rgba(48,82,140,.16);
  transform: perspective(1100px) rotateY(-4deg) rotateX(2deg);
  transition: transform .5s ease;
}
.network-card:hover { transform: perspective(1100px) rotateY(0) rotateX(0) translateY(-5px); }
.status-pill { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px 15px; margin-top: 14px; border-radius: 14px; background: #f6f9fd; color: var(--muted); font-size: 13px; }
.status-pill strong { color: var(--ink); }
.live-dot { display:inline-block; width:8px; height:8px; margin-right:6px; border-radius:50%; background:#19be83; box-shadow:0 0 0 5px rgba(25,190,131,.12); animation:pulse 1.8s infinite; }
.float-badge { position: absolute; z-index: 3; border: 1px solid var(--line); background: rgba(255,255,255,.92); backdrop-filter: blur(12px); box-shadow: var(--shadow-sm); border-radius: 15px; padding: 12px 15px; font-size: 13px; animation: float 4.5s ease-in-out infinite; }
.float-badge strong { display:block; font-size:16px; }
.float-badge.one { top: 55px; right: -20px; }
.float-badge.two { bottom: 55px; left: -24px; animation-delay: -2.1s; }

.metrics { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: rgba(255,255,255,.7); }
.metric-grid { display:grid; grid-template-columns:repeat(4,1fr); }
.metric { padding:30px; text-align:center; border-right:1px solid var(--line); }
.metric:last-child { border-right:0; }
.metric strong { display:block; font-size:31px; line-height:1.1; letter-spacing:-.03em; }
.metric span { color:var(--muted); font-size:13px; }

.grid-3 { display:grid; grid-template-columns:repeat(3,1fr); gap:22px; }
.grid-2 { display:grid; grid-template-columns:repeat(2,1fr); gap:24px; }
.card { background:rgba(255,255,255,.9); border:1px solid var(--line); border-radius:var(--radius); padding:28px; box-shadow:0 1px 0 rgba(20,40,70,.02); transition:transform .3s ease, box-shadow .3s ease, border-color .3s ease; }
.card:hover { transform:translateY(-6px); box-shadow:var(--shadow); border-color:#d5e0ee; }
.feature-icon { width:48px; height:48px; display:grid; place-items:center; color:var(--brand); border-radius:15px; margin-bottom:22px; background:linear-gradient(145deg,#edf5ff,#f3efff); }
.feature-icon .icon { width:25px; height:25px; }
.card p { color:var(--muted); font-size:15px; margin-bottom:0; }

.pricing-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:22px; align-items:stretch; }
.price-card { position:relative; display:flex; flex-direction:column; padding:32px; background:#fff; border:1px solid var(--line); border-radius:26px; box-shadow:var(--shadow-sm); }
.price-card.popular { transform:translateY(-12px); border:2px solid var(--brand); box-shadow:0 22px 60px rgba(41,101,255,.17); }
.price-tag { position:absolute; top:-14px; right:22px; border-radius:999px; color:#fff; background:linear-gradient(120deg,var(--brand),var(--brand-2)); padding:6px 13px; font-size:12px; font-weight:800; }
.price { margin:18px 0 22px; font-size:15px; color:var(--muted); }
.price strong { color:var(--ink); font-size:44px; line-height:1; }
.price-list { list-style:none; padding:0; margin:0 0 26px; flex:1; }
.price-list li { display:flex; gap:10px; align-items:flex-start; padding:9px 0; color:#46546c; font-size:14px; }
.price-list .icon { width:18px; height:18px; color:var(--success); flex:0 0 auto; margin-top:3px; }
.pricing-note { text-align:center; margin-top:24px; color:var(--muted); font-size:13px; }

.persona-card { display:flex; gap:18px; align-items:flex-start; }
.persona-card .feature-icon { flex:0 0 auto; margin:0; }
.persona-card p { margin:0; }
.tutorial-layout { display:grid; grid-template-columns:.9fr 1.1fr; gap:50px; align-items:center; }
.device-frame { padding:18px; background:#0e1b31; border-radius:30px; box-shadow:0 26px 60px rgba(21,44,81,.22); }
.device-screen { min-height:390px; overflow:hidden; border-radius:18px; background:linear-gradient(145deg,#f8fbff,#eef3fb); padding:26px; }
.device-top { display:flex; justify-content:space-between; align-items:center; margin-bottom:22px; }
.device-list { display:grid; gap:12px; }
.device-row { display:flex; align-items:center; justify-content:space-between; gap:15px; padding:14px; background:#fff; border:1px solid #e5ebf4; border-radius:13px; box-shadow:0 5px 16px rgba(46,76,120,.06); }
.device-row span:first-child { display:flex; align-items:center; gap:10px; font-weight:700; font-size:14px; }
.flag-dot { width:28px; height:28px; border-radius:9px; display:grid; place-items:center; background:#eaf2ff; color:var(--brand); font-size:11px; }
.latency { color:var(--success); font-size:12px; }
.tab-buttons { display:flex; flex-wrap:wrap; gap:10px; margin-bottom:24px; }
.tab-btn { border:1px solid var(--line); border-radius:12px; background:#fff; color:var(--muted); padding:10px 14px; cursor:pointer; font-weight:700; }
.tab-btn.active { background:var(--brand); color:#fff; border-color:var(--brand); }
.tab-panel { display:none; }
.tab-panel.active { display:block; animation:fadeUp .45s ease both; }
.steps { list-style:none; padding:0; margin:24px 0; counter-reset:step; }
.steps li { position:relative; padding:0 0 25px 48px; color:var(--muted); }
.steps li::before { counter-increment:step; content:counter(step); position:absolute; left:0; top:-2px; width:30px; height:30px; display:grid; place-items:center; border-radius:10px; color:#fff; background:linear-gradient(135deg,var(--brand),var(--brand-2)); font-size:13px; font-weight:800; }
.steps li:not(:last-child)::after { content:""; position:absolute; left:15px; top:31px; bottom:4px; width:1px; background:#dce5f1; }
.steps strong { display:block; color:var(--ink); margin-bottom:4px; }
.notice { padding:15px 17px; border:1px solid #cfe1ff; border-radius:14px; background:#f0f6ff; color:#365a91; font-size:14px; }

.quote-card { position:relative; }
.quote-card::before { content:"“"; position:absolute; right:24px; top:4px; font-size:76px; color:#eaf1ff; font-family:Georgia,serif; line-height:1; }
.quote-card p { position:relative; color:#34435b; min-height:104px; }
.reviewer { display:flex; align-items:center; gap:12px; margin-top:20px; }
.avatar { width:42px; height:42px; display:grid; place-items:center; border-radius:50%; color:#fff; background:linear-gradient(135deg,var(--brand),var(--brand-2)); font-weight:800; }
.reviewer small { display:block; color:var(--muted); }
.stars { color:#ffb02e; letter-spacing:2px; font-size:13px; }

.faq-list { max-width:860px; margin:0 auto; display:grid; gap:12px; }
.faq-item { background:#fff; border:1px solid var(--line); border-radius:16px; overflow:hidden; }
.faq-item summary { display:flex; justify-content:space-between; gap:18px; align-items:center; padding:20px 22px; font-weight:760; cursor:pointer; list-style:none; }
.faq-item summary::-webkit-details-marker { display:none; }
.faq-item summary::after { content:"+"; width:25px; height:25px; display:grid; place-items:center; border-radius:50%; background:var(--brand-soft); color:var(--brand); flex:0 0 auto; transition:transform .25s; }
.faq-item[open] summary::after { transform:rotate(45deg); }
.faq-answer { padding:0 22px 20px; color:var(--muted); }

.article-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:22px; }
.article-card { display:flex; flex-direction:column; padding:0; overflow:hidden; }
.article-cover { position:relative; height:180px; display:grid; place-items:center; overflow:hidden; background:linear-gradient(140deg,#eaf3ff,#f1ecff); }
.article-cover::before,.article-cover::after { content:""; position:absolute; border:1px solid rgba(38,101,255,.18); border-radius:50%; animation:ripple 4s linear infinite; }
.article-cover::before { width:90px; height:90px; }
.article-cover::after { width:150px; height:150px; animation-delay:-2s; }
.article-cover .icon { width:52px; height:52px; color:var(--brand); z-index:1; }
.article-body { padding:24px; display:flex; flex-direction:column; flex:1; }
.article-meta { display:flex; gap:12px; flex-wrap:wrap; color:var(--muted); font-size:12px; margin-bottom:12px; }
.article-body h3 { font-size:19px; }
.article-body p { flex:1; }
.text-link { display:inline-flex; gap:6px; align-items:center; color:var(--brand); font-weight:750; font-size:14px; }
.text-link:hover { gap:10px; }

.cta-band { padding:48px; display:flex; align-items:center; justify-content:space-between; gap:32px; border-radius:28px; color:#fff; background:linear-gradient(120deg,#1268ff,#6d47f5); box-shadow:0 24px 64px rgba(51,91,236,.25); overflow:hidden; position:relative; }
.cta-band::after { content:""; position:absolute; width:300px; height:300px; right:-90px; top:-130px; border-radius:50%; border:46px solid rgba(255,255,255,.09); }
.cta-band h2 { color:#fff; margin-bottom:8px; font-size:34px; }
.cta-band p { color:rgba(255,255,255,.78); margin:0; }
.cta-band .btn { background:#fff; color:var(--brand); position:relative; z-index:1; flex:0 0 auto; }

.site-footer { padding:70px 0 28px; background:#0d192c; color:#c5cfdd; }
.footer-grid { display:grid; grid-template-columns:1.7fr repeat(3,1fr); gap:42px; padding-bottom:48px; }
.footer-brand .brand { color:#fff; margin-bottom:18px; }
.footer-brand p { max-width:400px; color:#8f9eb3; font-size:14px; }
.footer-col h4 { color:#fff; font-size:14px; letter-spacing:.02em; margin-bottom:16px; }
.footer-links { display:grid; gap:10px; color:#93a2b6; font-size:14px; }
.footer-links a:hover { color:#fff; }
.footer-bottom { display:flex; justify-content:space-between; gap:20px; flex-wrap:wrap; padding-top:24px; border-top:1px solid rgba(255,255,255,.09); font-size:12px; color:#7f8ca0; }

.page-hero { padding:72px 0 60px; background:linear-gradient(180deg,#f7faff,rgba(255,255,255,0)); }
.breadcrumb { display:flex; flex-wrap:wrap; gap:7px; align-items:center; color:var(--muted); font-size:13px; margin-bottom:24px; }
.breadcrumb a:hover { color:var(--brand); }
.page-hero h1 { font-size:clamp(36px,5vw,58px); max-width:890px; }
.page-hero .lead { max-width:820px; }
.article-layout { display:grid; grid-template-columns:minmax(0,780px) 280px; align-items:start; gap:54px; }
.article-content { min-width:0; }
.article-content h2 { font-size:30px; margin-top:52px; scroll-margin-top:100px; }
.article-content h3 { font-size:22px; margin-top:34px; scroll-margin-top:100px; }
.article-content p, .article-content li { color:#3f4e65; }
.article-content ul,.article-content ol { padding-left:24px; margin:18px 0 24px; }
.article-content li { margin:8px 0; }
.article-content a { color:var(--brand); text-decoration:underline; text-decoration-color:rgba(23,105,255,.25); text-underline-offset:3px; }
.article-content blockquote { margin:28px 0; padding:18px 20px; border-left:4px solid var(--brand); background:#f3f7ff; border-radius:0 14px 14px 0; color:#365a91; }
.article-content .compare-table { width:100%; border-collapse:separate; border-spacing:0; overflow:hidden; border:1px solid var(--line); border-radius:14px; margin:25px 0; font-size:14px; }
.compare-table th,.compare-table td { padding:14px 16px; text-align:left; border-bottom:1px solid var(--line); }
.compare-table th { background:#f5f8fc; color:var(--ink); }
.compare-table tr:last-child td { border-bottom:0; }
.article-aside { position:sticky; top:98px; }
.toc { padding:22px; border:1px solid var(--line); border-radius:18px; background:#fff; box-shadow:var(--shadow-sm); }
.toc h3 { font-size:15px; }
.toc ol { padding-left:20px; margin:0; color:var(--muted); font-size:13px; }
.toc li { margin:8px 0; }
.toc a:hover { color:var(--brand); }
.article-faq { margin-top:54px; padding-top:20px; border-top:1px solid var(--line); }
.related { margin-top:55px; }
.related-links { display:grid; grid-template-columns:repeat(3,1fr); gap:14px; }
.related-link { padding:18px; border:1px solid var(--line); border-radius:14px; font-size:14px; font-weight:700; background:#fff; transition:.25s; }
.related-link:hover { border-color:#bcd2fa; transform:translateY(-3px); box-shadow:var(--shadow-sm); }
.legal-content { max-width:840px; }
.legal-content h2 { margin-top:42px; font-size:28px; }
.legal-content h3 { margin-top:28px; font-size:20px; }
.legal-content p,.legal-content li { color:#46546c; }

.reveal { opacity:0; transform:translateY(22px); transition:opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity:1; transform:none; }
.delay-1 { transition-delay:.08s; }.delay-2 { transition-delay:.16s; }.delay-3 { transition-delay:.24s; }
.back-top { position:fixed; right:24px; bottom:24px; z-index:50; width:45px; height:45px; border:0; border-radius:14px; display:grid; place-items:center; color:#fff; background:linear-gradient(135deg,var(--brand),var(--brand-2)); box-shadow:0 12px 30px rgba(46,89,230,.25); cursor:pointer; opacity:0; pointer-events:none; transform:translateY(10px); transition:.25s; }
.back-top.show { opacity:1; pointer-events:auto; transform:none; }

@keyframes float { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-12px)} }
@keyframes breathe { 0%,100%{transform:scale(.96);opacity:.78} 50%{transform:scale(1.06);opacity:1} }
@keyframes pulse { 0%,100%{box-shadow:0 0 0 4px rgba(25,190,131,.12)} 50%{box-shadow:0 0 0 9px rgba(25,190,131,0)} }
@keyframes ripple { 0%{transform:scale(.75);opacity:.8} 100%{transform:scale(1.35);opacity:0} }
@keyframes fadeUp { from{opacity:0;transform:translateY(8px)} to{opacity:1;transform:none} }

@media (prefers-reduced-motion:reduce) {
  *,*::before,*::after { animation-duration:.01ms!important; animation-iteration-count:1!important; scroll-behavior:auto!important; transition-duration:.01ms!important; }
  .reveal { opacity:1; transform:none; }
}
@media (max-width:980px) {
  .nav-links { position:fixed; left:20px; right:20px; top:82px; display:none; flex-direction:column; align-items:stretch; gap:0; padding:12px; border:1px solid var(--line); border-radius:18px; background:#fff; box-shadow:var(--shadow); }
  .nav-links.open { display:flex; }
  .nav-links a { padding:12px; border-radius:10px; }
  .nav-links a:hover { background:var(--surface); }
  .nav-actions .btn-ghost { display:none; }
  .menu-btn { display:block; }
  .hero-grid,.tutorial-layout { grid-template-columns:1fr; }
  .hero-copy { text-align:center; }
  .hero-copy .lead { margin-left:auto; margin-right:auto; }
  .hero-actions,.trust-line { justify-content:center; }
  .hero-visual { min-height:460px; max-width:670px; margin:auto; }
  .float-badge.one { right:0; }.float-badge.two { left:0; }
  .grid-3,.article-grid { grid-template-columns:repeat(2,1fr); }
  .pricing-grid { grid-template-columns:1fr; max-width:620px; margin:auto; }
  .price-card.popular { transform:none; }
  .article-layout { grid-template-columns:1fr; }
  .article-aside { position:static; order:-1; }
  .toc ol { columns:2; }
  .footer-grid { grid-template-columns:2fr 1fr 1fr; }
  .footer-brand { grid-column:1/-1; }
}
@media (max-width:680px) {
  .container { width:min(100% - 28px,var(--container)); }
  .section { padding:74px 0; }
  .nav { min-height:66px; }
  .nav-actions .btn { display:none; }
  .hero { padding:62px 0 54px; }
  h1 { font-size:41px; }
  .hero-visual { min-height:365px; }
  .network-card { transform:none; border-radius:22px; padding:12px; }
  .float-badge { display:none; }
  .metric-grid { grid-template-columns:repeat(2,1fr); }
  .metric:nth-child(2) { border-right:0; }
  .metric:nth-child(-n+2) { border-bottom:1px solid var(--line); }
  .grid-3,.grid-2,.article-grid { grid-template-columns:1fr; }
  .card { padding:23px; }
  .device-screen { min-height:340px; padding:18px; }
  .cta-band { padding:34px 25px; display:block; text-align:center; }
  .cta-band h2 { font-size:28px; }
  .cta-band .btn { margin-top:22px; }
  .footer-grid { grid-template-columns:1fr 1fr; gap:30px; }
  .footer-brand { grid-column:1/-1; }
  .page-hero { padding:54px 0 42px; }
  .article-content h2 { font-size:26px; }
  .compare-table { display:block; overflow-x:auto; white-space:nowrap; }
  .toc ol { columns:1; }
  .related-links { grid-template-columns:1fr; }
}