:root {
    --primary: #2980FE;
    --primary-hover: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1F2937;
    --muted: #667085;
    --soft: #F5F7FB;
    --line: #E5EAF3;
    --panel: #FFFFFF;
    --deep: #111827;
    --shadow: 0 18px 50px 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;
}
.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255,255,255,.94);
    border-bottom: 1px solid rgba(229,234,243,.9);
    backdrop-filter: blur(16px);
}
.header-inner {
    width: min(1180px, calc(100% - 28px));
    margin: 0 auto;
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand, .footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #172033;
    letter-spacing: .02em;
}
.logo, .footer-brand img {
    width: 40px;
    height: 40px;
    border-radius: 14px;
    object-fit: cover;
}
.nav-toggle {
    width: 44px;
    height: 44px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: #fff;
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
}
.nav-toggle span {
    width: 18px;
    height: 2px;
    background: #263348;
    border-radius: 999px;
}
.site-nav {
    display: none;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 70px;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: #fff;
    box-shadow: var(--shadow);
}
.site-nav.open { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.site-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #475467;
    font-size: 14px;
    transition: .2s ease;
}
.site-nav a.active, .site-nav a:hover { color: var(--primary); background: #EEF5FF; }
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 12px 28px rgba(41,128,254,.22);
    transition: .2s ease;
}
.download-btn:hover { background: var(--primary-hover); transform: translateY(-1px); }
.section {
    padding: 64px 0;
}
.section-soft { background: var(--soft); }
.section-title {
    margin: 0 0 14px;
    font-size: clamp(28px, 4vw, 44px);
    line-height: 1.16;
    color: var(--deep);
    letter-spacing: -.03em;
}
.section-lead {
    margin: 0 0 26px;
    color: var(--muted);
    max-width: 760px;
}
.badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 16px;
    padding: 6px 12px;
    border-radius: 999px;
    background: #EEF5FF;
    color: var(--primary);
    font-size: 13px;
    font-weight: 800;
}
.link-more {
    color: var(--primary);
    font-weight: 800;
}
.vpn-network-hero {
    position: relative;
    isolation: isolate;
    overflow: hidden;
    padding: 76px 0 52px;
    color: #fff;
    background: var(--gradient);
}
.vpn-network-hero:before {
    content: "";
    position: absolute;
    inset: 0;
    z-index: -1;
    opacity: .38;
    background:
        radial-gradient(circle at 18% 18%, rgba(255,255,255,.32) 0 3px, transparent 4px),
        radial-gradient(circle at 78% 32%, rgba(255,255,255,.24) 0 4px, transparent 5px),
        radial-gradient(circle at 58% 74%, rgba(255,255,255,.22) 0 3px, transparent 4px),
        linear-gradient(135deg, transparent 0 18%, rgba(255,255,255,.22) 18.3% 18.8%, transparent 19.1% 45%, rgba(255,255,255,.16) 45.2% 45.8%, transparent 46.1%);
}
.hero-grid {
    display: grid;
    gap: 34px;
    align-items: center;
}
.hero-copy h1 {
    margin: 0 0 18px;
    font-size: clamp(38px, 9vw, 66px);
    line-height: 1.04;
    letter-spacing: -.05em;
}
.hero-copy p {
    margin: 0 0 24px;
    color: rgba(255,255,255,.86);
    font-size: 17px;
}
.hero-tags, .status-tags, .inline-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}
.hero-tags { margin-top: 22px; }
.hero-tags span, .status-tags span, .inline-tags span {
    display: inline-flex;
    align-items: center;
    padding: 7px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,.16);
    color: #fff;
    border: 1px solid rgba(255,255,255,.26);
    font-size: 13px;
    font-weight: 700;
}
.hero-visual {
    position: relative;
    padding: 22px;
    border-radius: 34px;
    background: rgba(255,255,255,.14);
    border: 1px solid rgba(255,255,255,.26);
    box-shadow: 0 28px 80px rgba(31,41,55,.22);
}
.hero-visual img {
    width: min(440px, 100%);
    margin: 0 auto;
    border-radius: 28px;
}
.float-card {
    position: static;
    margin-top: 12px;
    display: inline-flex;
    padding: 9px 12px;
    border-radius: 16px;
    background: rgba(255,255,255,.9);
    color: #23324A;
    font-size: 13px;
    font-weight: 800;
    box-shadow: 0 14px 30px rgba(31,41,55,.14);
}
.node-overview {
    margin-top: -34px;
    position: relative;
    z-index: 3;
}
.node-grid, .card-grid, .risk-grid, .faq-grid, .policy-grid, .steps-grid {
    display: grid;
    gap: 18px;
}
.node-card, .feature-card, .risk-card, .faq-item, .step-card, .note-card {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 12px 34px rgba(31,41,55,.05);
}
.node-card small, .feature-card small {
    display: inline-flex;
    padding: 4px 10px;
    border-radius: 999px;
    background: #EEF5FF;
    color: var(--primary);
    font-weight: 800;
}
.node-card h3, .feature-card h3, .risk-card h3, .faq-item h3, .step-card h3, .note-card h3 {
    margin: 12px 0 8px;
    color: #172033;
    line-height: 1.25;
}
.node-card p, .feature-card p, .risk-card p, .faq-item p, .step-card p, .note-card p {
    margin: 0 0 12px;
    color: var(--muted);
}
.split-section {
    display: grid;
    gap: 28px;
    align-items: center;
}
.visual-panel {
    position: relative;
    padding: 18px;
    border-radius: 32px;
    background: linear-gradient(180deg, #fff, #F5F8FF);
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}
.visual-panel img { border-radius: 24px; margin: 0 auto; }
.bullet-list, .check-list, .simple-list {
    margin: 18px 0 24px;
    padding: 0;
    list-style: none;
    display: grid;
    gap: 10px;
}
.bullet-list li, .check-list li, .simple-list li {
    position: relative;
    padding-left: 24px;
    color: #344054;
}
.bullet-list li:before, .check-list li:before, .simple-list li:before {
    content: "";
    position: absolute;
    left: 0;
    top: .72em;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--primary);
}
.global-nodes-section {
    position: relative;
    overflow: hidden;
    background: #F6F8FC;
}
.map-panel {
    position: relative;
    padding: 24px;
    min-height: 310px;
    border-radius: 32px;
    background:
        radial-gradient(circle at 18% 30%, rgba(41,128,254,.22) 0 5px, transparent 6px),
        radial-gradient(circle at 76% 26%, rgba(123,78,241,.22) 0 5px, transparent 6px),
        radial-gradient(circle at 52% 72%, rgba(184,77,218,.18) 0 5px, transparent 6px),
        linear-gradient(135deg, #FFFFFF, #EEF4FF);
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}
.map-panel:before {
    content: "";
    position: absolute;
    inset: 38px;
    border-radius: 24px;
    background: linear-gradient(22deg, transparent 0 25%, rgba(41,128,254,.24) 25.2% 26%, transparent 26.2% 55%, rgba(123,78,241,.18) 55.2% 56%, transparent 56.2%);
}
.map-panel img { position: relative; z-index: 1; margin: 0 auto; }
.speed-lines {
    display: grid;
    gap: 12px;
    margin: 18px 0 24px;
}
.speed-line {
    padding: 14px;
    border-radius: 16px;
    background: #fff;
    border: 1px solid var(--line);
}
.speed-line span { display: block; height: 8px; border-radius: 999px; background: linear-gradient(90deg, #2980FE, #B84DDA); }
.privacy-panel, .tech-panel {
    padding: 24px;
    border-radius: 30px;
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}
.privacy-panel .inline-tags span { background: #EEF5FF; color: var(--primary); border-color: #D9E8FF; }
.policy-grid { grid-template-columns: 1fr; }
.policy-card {
    padding: 22px;
    border-radius: 24px;
    background: linear-gradient(180deg, #FFFFFF, #F7FAFF);
    border: 1px solid var(--line);
}
.device-strip {
    display: grid;
    gap: 14px;
    margin-top: 18px;
}
.device-strip div {
    padding: 16px;
    border-radius: 20px;
    border: 1px solid var(--line);
    background: #fff;
}
.process-steps .step-card {
    position: relative;
    padding-top: 54px;
}
.step-num {
    position: absolute;
    left: 22px;
    top: 20px;
    width: 28px;
    height: 28px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    font-weight: 900;
    font-size: 13px;
}
.risk-card {
    border-left: 4px solid var(--primary);
}
.risk-card strong { display: block; color: #172033; }
.faq-item h3 { font-size: 18px; }
.cta-section {
    padding: 64px 0;
    text-align: center;
    color: #fff;
    background: var(--gradient);
    position: relative;
    overflow: hidden;
}
.cta-section:before {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 18% 18%, rgba(255,255,255,.2), transparent 28%), radial-gradient(circle at 82% 70%, rgba(255,255,255,.18), transparent 32%);
}
.cta-section .container { position: relative; }
.cta-section h2 { margin: 0 0 12px; font-size: clamp(28px, 5vw, 44px); line-height: 1.2; }
.cta-section p { margin: 0 auto 24px; color: rgba(255,255,255,.84); max-width: 720px; }
.page-hero {
    padding: 58px 0 38px;
    background: linear-gradient(180deg, #F6F8FF, #fff);
    border-bottom: 1px solid var(--line);
}
.page-hero h1 {
    margin: 0 0 14px;
    font-size: clamp(32px, 7vw, 54px);
    line-height: 1.12;
    letter-spacing: -.04em;
    color: #111827;
}
.page-hero p { margin: 0; color: var(--muted); max-width: 820px; }
.content-layout {
    display: grid;
    gap: 24px;
    align-items: start;
}
.article-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 24px;
    box-shadow: 0 12px 36px rgba(31,41,55,.04);
}
.article-card h2 { margin: 0 0 12px; color: #172033; }
.article-card p { color: #4B5563; }
.side-card {
    padding: 22px;
    border-radius: 24px;
    background: #F6F8FC;
    border: 1px solid var(--line);
}
.side-card a { display: block; color: var(--primary); font-weight: 800; margin-top: 10px; }
.download-page-card {
    max-width: 820px;
    margin: 0 auto;
    text-align: center;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 32px;
    padding: 32px;
    box-shadow: var(--shadow);
}
.download-page-card .download-btn { margin: 8px 0 24px; }
.steps-list {
    counter-reset: step;
    list-style: none;
    padding: 0;
    margin: 20px 0 0;
    display: grid;
    gap: 12px;
    text-align: left;
}
.steps-list li {
    counter-increment: step;
    padding: 14px 14px 14px 52px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: #F8FAFF;
    position: relative;
}
.steps-list li:before {
    content: counter(step);
    position: absolute;
    left: 14px;
    top: 14px;
    width: 26px;
    height: 26px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
}
.site-footer {
    background: #F8FAFC;
    border-top: 1px solid var(--line);
    padding: 48px 0 22px;
}
.footer-grid {
    display: grid;
    gap: 24px;
}
.footer-grid p { color: var(--muted); margin: 14px 0 0; }
.footer-grid h3 { margin: 0 0 12px; font-size: 16px; color: #172033; }
.footer-grid a:not(.footer-brand) { display: block; color: #667085; margin: 8px 0; }
.footer-grid a:hover { color: var(--primary); }
.footer-bottom {
    margin-top: 28px;
    padding-top: 20px;
    border-top: 1px solid var(--line);
    display: flex;
    flex-direction: column;
    gap: 8px;
    color: #667085;
    font-size: 14px;
}
@media (min-width: 700px) {
    .node-grid { grid-template-columns: repeat(2, 1fr); }
    .card-grid, .risk-grid, .faq-grid, .steps-grid { grid-template-columns: repeat(2, 1fr); }
    .policy-grid { grid-template-columns: repeat(3, 1fr); }
    .device-strip { grid-template-columns: repeat(3, 1fr); }
    .footer-grid { grid-template-columns: 1.4fr 1fr 1fr 1fr; }
    .footer-bottom { flex-direction: row; justify-content: space-between; }
}
@media (min-width: 980px) {
    .nav-toggle { display: none; }
    .site-nav {
        position: static;
        display: flex;
        align-items: center;
        gap: 2px;
        padding: 0;
        border: 0;
        box-shadow: none;
        background: transparent;
    }
    .hero-grid, .split-section, .content-layout { grid-template-columns: 1.05fr .95fr; }
    .hero-visual { min-height: 500px; display: flex; align-items: center; }
    .float-card { position: absolute; margin-top: 0; }
    .float-card.card-a { left: 12px; top: 58px; }
    .float-card.card-b { right: 14px; top: 126px; }
    .float-card.card-c { left: 26px; bottom: 80px; }
    .float-card.card-d { right: 30px; bottom: 34px; }
    .node-grid { grid-template-columns: repeat(4, 1fr); }
    .card-grid { grid-template-columns: repeat(3, 1fr); }
    .risk-grid { grid-template-columns: repeat(4, 1fr); }
    .faq-grid { grid-template-columns: repeat(2, 1fr); }
    .section { padding: 84px 0; }
    .article-card { padding: 34px; }
}