:root {
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #1F2937;
    --muted: #667085;
    --light: #F6F8FC;
    --line: #E5EAF2;
    --panel: #FFFFFF;
    --shadow: 0 18px 45px rgba(31, 41, 55, .08);
    --radius: 24px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    color: var(--text);
    background: #fff;
    line-height: 1.75;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.section { padding: 58px 0; }
.section-muted { background: var(--light); }
.eyebrow, .badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 12px;
    border-radius: 999px;
    background: rgba(41,128,254,.1);
    color: var(--blue);
    font-weight: 700;
    font-size: 13px;
}
.section-title { font-size: clamp(28px, 4vw, 44px); line-height: 1.18; margin: 14px 0 14px; letter-spacing: -.02em; }
.section-lead { color: var(--muted); max-width: 780px; margin: 0 0 24px; }
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--line);
}
.nav-wrap {
    width: min(1180px, calc(100% - 28px));
    margin: 0 auto;
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 900; font-size: 22px; }
.brand img { width: 38px; height: 38px; border-radius: 12px; object-fit: cover; box-shadow: 0 8px 22px rgba(41,128,254,.16); }
.site-nav { display: none; width: 100%; flex-direction: column; gap: 10px; padding: 12px 0 18px; }
.site-nav a { color: #334155; font-weight: 650; padding: 10px 12px; border-radius: 12px; }
.site-nav a:hover { background: #F1F5F9; color: var(--blue); }
.nav-toggle { position: absolute; opacity: 0; pointer-events: none; }
.nav-toggle-label { padding: 9px 13px; border-radius: 14px; border: 1px solid var(--line); font-weight: 800; color: var(--blue); }
.nav-toggle:checked ~ .site-nav { display: flex; position: absolute; left: 0; top: 70px; background: #fff; border-bottom: 1px solid var(--line); padding-left: 16px; padding-right: 16px; box-shadow: var(--shadow); }
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: var(--blue);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 12px 26px rgba(41,128,254,.28);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}
.download-btn:hover { background: var(--blue-dark); transform: translateY(-2px); box-shadow: 0 16px 32px rgba(23,104,232,.3); }
.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #fff;
    background: var(--gradient);
    padding: 56px 0 44px;
}
.vpn-network-hero::before, .vpn-network-hero::after {
    content: "";
    position: absolute;
    border-radius: 999px;
    background: rgba(255,255,255,.16);
    filter: blur(8px);
}
.vpn-network-hero::before { width: 300px; height: 300px; right: -70px; top: -70px; }
.vpn-network-hero::after { width: 230px; height: 230px; left: -90px; bottom: -100px; }
.hero-grid { position: relative; z-index: 1; display: grid; gap: 34px; align-items: center; }
.hero-copy h1 { font-size: clamp(38px, 8vw, 68px); line-height: 1.08; margin: 12px 0 18px; letter-spacing: -.045em; }
.hero-copy p { font-size: 17px; color: rgba(255,255,255,.88); margin: 0 0 24px; max-width: 620px; }
.hero-tags, .status-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.hero-tags span, .status-tags span { border: 1px solid rgba(255,255,255,.28); background: rgba(255,255,255,.13); padding: 7px 12px; border-radius: 999px; font-size: 13px; font-weight: 700; }
.hero-visual { position: relative; min-height: 330px; display: grid; place-items: center; }
.network-orbit {
    position: absolute;
    inset: 8px;
    border-radius: 32px;
    border: 1px solid rgba(255,255,255,.22);
    background-image: radial-gradient(circle at 20% 30%, rgba(255,255,255,.5) 0 3px, transparent 4px), radial-gradient(circle at 80% 42%, rgba(255,255,255,.5) 0 3px, transparent 4px), radial-gradient(circle at 48% 78%, rgba(255,255,255,.5) 0 3px, transparent 4px), linear-gradient(135deg, rgba(255,255,255,.2), rgba(255,255,255,.02));
}
.hero-device { width: min(430px, 88%); border-radius: 30px; box-shadow: 0 30px 80px rgba(19, 31, 73, .28); position: relative; z-index: 2; }
.float-card { position: absolute; z-index: 3; background: rgba(255,255,255,.92); color: #1F2937; border: 1px solid rgba(255,255,255,.7); box-shadow: var(--shadow); border-radius: 18px; padding: 10px 14px; font-weight: 800; font-size: 13px; }
.float-card.one { left: 2%; top: 18%; }
.float-card.two { right: 2%; top: 28%; }
.float-card.three { left: 8%; bottom: 18%; }
.float-card.four { right: 8%; bottom: 12%; }
.node-overview { margin-top: -28px; position: relative; z-index: 4; }
.node-grid { display: grid; gap: 16px; }
.node-card, .feature-card, .risk-card, .faq-item, .info-card, .step-card {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 12px 30px rgba(31,41,55,.05);
}
.node-card .tag { color: var(--blue); font-weight: 900; font-size: 13px; }
.node-card h3, .feature-card h3, .risk-card h3, .info-card h3, .step-card h3 { margin: 8px 0 8px; font-size: 20px; }
.node-card p, .feature-card p, .risk-card p, .info-card p, .step-card p, .faq-item p { color: var(--muted); margin: 0 0 12px; }
.text-link { color: var(--blue); font-weight: 800; }
.split-section { display: grid; gap: 28px; align-items: center; }
.visual-panel { position: relative; background: #fff; border: 1px solid var(--line); border-radius: 32px; padding: 16px; box-shadow: var(--shadow); overflow: hidden; }
.visual-panel::before { content: ""; position: absolute; inset: 0; background: radial-gradient(circle at 15% 15%, rgba(41,128,254,.12), transparent 30%), radial-gradient(circle at 85% 18%, rgba(184,77,218,.12), transparent 30%); pointer-events: none; }
.visual-panel img { position: relative; border-radius: 24px; width: 100%; }
.check-list, .mini-list { list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 10px; }
.check-list li, .mini-list li { position: relative; padding-left: 28px; color: #344054; }
.check-list li::before, .mini-list li::before { content: ""; position: absolute; left: 0; top: .62em; width: 9px; height: 9px; border-radius: 999px; background: var(--blue); }
.global-nodes-section {
    position: relative;
    overflow: hidden;
    background: #F7FAFF;
}
.map-panel {
    background: #fff;
    border-radius: 32px;
    border: 1px solid var(--line);
    padding: 18px;
    box-shadow: var(--shadow);
    background-image: radial-gradient(circle at 18% 30%, rgba(41,128,254,.18) 0 5px, transparent 6px), radial-gradient(circle at 70% 42%, rgba(123,78,241,.18) 0 5px, transparent 6px), radial-gradient(circle at 48% 74%, rgba(184,77,218,.16) 0 5px, transparent 6px), linear-gradient(120deg, rgba(41,128,254,.05), rgba(184,77,218,.04));
}
.map-panel img { border-radius: 26px; margin-bottom: 16px; }
.node-lines { display: grid; gap: 12px; }
.node-line { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px 14px; background: rgba(255,255,255,.8); border: 1px solid var(--line); border-radius: 16px; color: #475467; font-weight: 700; }
.speed-cards { display: grid; gap: 12px; margin-top: 18px; }
.speed-card { padding: 16px; border-radius: 18px; border: 1px solid var(--line); background: #fff; }
.speed-card strong { display:block; color: var(--blue); margin-bottom: 4px; }
.privacy-panel { background: #fff; border: 1px solid var(--line); border-radius: 32px; padding: 22px; box-shadow: var(--shadow); }
.privacy-tags { display: flex; flex-wrap: wrap; gap: 10px; margin: 16px 0; }
.privacy-tags span { padding: 8px 12px; border-radius: 999px; background: #F1F7FF; color: var(--blue); font-weight: 800; }
.policy-grid, .feature-grid, .risk-grid, .faq-grid { display: grid; gap: 16px; }
.device-layout { display: grid; gap: 20px; align-items: center; }
.device-cards { display: grid; gap: 12px; }
.device-card { background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 18px; }
.protocol-panel { border-radius: 32px; background: #101828; color: #fff; padding: 26px; position: relative; overflow: hidden; }
.protocol-panel::before { content: ""; position: absolute; inset: 0; background: radial-gradient(circle at 82% 12%, rgba(41,128,254,.32), transparent 34%), radial-gradient(circle at 16% 86%, rgba(184,77,218,.25), transparent 32%); }
.protocol-panel > * { position: relative; }
.protocol-grid { display: grid; gap: 14px; margin-top: 18px; }
.protocol-item { background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.14); border-radius: 18px; padding: 16px; }
.process-steps { display: grid; gap: 14px; }
.step-number { width: 38px; height: 38px; display: grid; place-items: center; border-radius: 14px; background: var(--blue); color: #fff; font-weight: 900; }
.risk-card { border-left: 4px solid var(--blue); }
.risk-card strong { color: var(--text); display: block; margin-top: 10px; }
.faq-item h3 { margin: 0 0 8px; font-size: 18px; }
.cta-section { background: var(--gradient); color: #fff; border-radius: 34px; padding: 42px 24px; text-align: center; overflow: hidden; position: relative; }
.cta-section p { color: rgba(255,255,255,.86); max-width: 700px; margin: 0 auto 22px; }
.page-hero { background: linear-gradient(180deg, #F4F7FF 0%, #fff 100%); padding: 44px 0 34px; border-bottom: 1px solid var(--line); }
.page-hero h1 { font-size: clamp(32px, 6vw, 54px); line-height: 1.12; margin: 14px 0; letter-spacing: -.035em; }
.page-hero p { color: var(--muted); max-width: 820px; margin: 0; }
.content-layout { display: grid; gap: 22px; align-items: start; }
.article-panel { background: #fff; border: 1px solid var(--line); border-radius: 28px; padding: 24px; box-shadow: 0 12px 30px rgba(31,41,55,.05); }
.article-panel h2 { margin-top: 0; font-size: 26px; }
.article-panel p { color: #475467; }
.sidebar { display: grid; gap: 16px; }
.tip-box { border: 1px solid var(--line); border-radius: 22px; padding: 18px; background: #F8FBFF; }
.tip-box h3 { margin: 0 0 8px; }
.page-cta { margin-top: 22px; padding: 22px; border-radius: 26px; background: #F6F8FC; border: 1px solid var(--line); }
.steps-list { counter-reset: steps; list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 12px; }
.steps-list li { counter-increment: steps; position: relative; padding: 16px 16px 16px 58px; background: #fff; border: 1px solid var(--line); border-radius: 18px; }
.steps-list li::before { content: counter(steps); position: absolute; left: 16px; top: 16px; width: 30px; height: 30px; border-radius: 12px; display: grid; place-items: center; background: var(--blue); color: #fff; font-weight: 900; }
.download-card { background: #fff; border: 1px solid var(--line); border-radius: 32px; padding: 28px; box-shadow: var(--shadow); }
.download-card .download-btn { margin-top: 18px; }
.site-footer { background: #111827; color: #D1D5DB; padding-top: 44px; }
.footer-grid { display: grid; gap: 24px; }
.footer-brand { color: #fff; font-size: 24px; font-weight: 900; margin-bottom: 8px; }
.site-footer h3 { color: #fff; margin: 0 0 10px; }
.site-footer a { display: block; color: #D1D5DB; margin: 7px 0; }
.site-footer a:hover { color: #fff; }
.footer-bottom { margin-top: 34px; padding: 18px; text-align: center; border-top: 1px solid rgba(255,255,255,.08); color: #9CA3AF; font-size: 14px; }
@media (min-width: 720px) {
    .node-grid { grid-template-columns: repeat(2, 1fr); }
    .policy-grid, .feature-grid, .risk-grid, .faq-grid { grid-template-columns: repeat(2, 1fr); }
    .process-steps { grid-template-columns: repeat(2, 1fr); }
    .speed-cards { grid-template-columns: repeat(3, 1fr); }
    .footer-grid { grid-template-columns: 1.5fr 1fr 1fr 1fr; }
}
@media (min-width: 980px) {
    .nav-toggle-label { display: none; }
    .site-nav { display: flex; flex-direction: row; align-items: center; justify-content: flex-end; width: auto; padding: 0; gap: 2px; }
    .site-nav a { font-size: 14px; padding: 9px 10px; }
    .hero-grid { grid-template-columns: 1.05fr .95fr; }
    .vpn-network-hero { padding: 86px 0 72px; }
    .node-grid { grid-template-columns: repeat(4, 1fr); }
    .split-section { grid-template-columns: 1fr 1fr; }
    .split-section.reverse .visual-panel, .split-section.reverse .map-panel { order: 2; }
    .device-layout { grid-template-columns: .9fr 1.1fr; }
    .policy-grid { grid-template-columns: repeat(3, 1fr); }
    .feature-grid { grid-template-columns: repeat(3, 1fr); }
    .risk-grid { grid-template-columns: repeat(3, 1fr); }
    .faq-grid { grid-template-columns: repeat(2, 1fr); }
    .process-steps { grid-template-columns: repeat(3, 1fr); }
    .content-layout { grid-template-columns: minmax(0, 1fr) 310px; }
    .article-panel { padding: 34px; }
}
@media (max-width: 420px) {
    .container { width: min(100% - 24px, 1120px); }
    .download-btn { width: 100%; }
    .float-card { position: static; margin: 8px; display: inline-flex; }
    .hero-visual { display: block; min-height: auto; }
    .network-orbit { display: none; }
    .hero-device { width: 100%; margin-top: 18px; }
}