:root {
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-hover: #1768E8;
    --text: #182033;
    --muted: #667085;
    --soft: #F5F7FB;
    --soft-blue: #F2F6FF;
    --line: #E6EAF2;
    --white: #FFFFFF;
    --panel: #FBFCFF;
    --shadow: 0 18px 48px rgba(26, 44, 94, 0.10);
    --radius-lg: 34px;
    --radius-md: 24px;
    --radius-sm: 18px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
    color: var(--text);
    background: #F8FAFE;
    line-height: 1.75;
    overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
p { margin: 0 0 16px; color: var(--muted); }
h1, h2, h3 { margin: 0 0 16px; color: var(--text); line-height: 1.2; letter-spacing: -0.02em; }
h1 { font-size: clamp(34px, 8vw, 64px); }
h2 { font-size: clamp(28px, 5vw, 44px); }
h3 { font-size: 22px; }
.container { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.section { padding: 72px 0; }
.section-soft { background: var(--soft); }
.section-title { max-width: 760px; margin-bottom: 32px; }
.section-title.center { text-align: center; margin-left: auto; margin-right: auto; }
.eyebrow, .category-badge {
    display: inline-flex; align-items: center; gap: 8px; padding: 7px 12px; margin-bottom: 14px;
    border-radius: 999px; color: var(--blue); background: #EBF3FF; font-size: 14px; font-weight: 700;
}
.site-header {
    position: sticky; top: 0; z-index: 20; background: rgba(255, 255, 255, 0.88);
    border-bottom: 1px solid rgba(230, 234, 242, 0.88); backdrop-filter: blur(18px);
}
.header-inner {
    width: min(1180px, calc(100% - 28px)); margin: 0 auto; min-height: 72px;
    display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; color: #17203A; }
.logo { width: 38px; height: 38px; border-radius: 12px; object-fit: cover; background: #fff; }
.brand-text { font-size: 20px; }
.site-nav {
    display: none; position: absolute; left: 14px; right: 14px; top: 72px; padding: 14px;
    border: 1px solid var(--line); border-radius: 22px; background: #fff; box-shadow: var(--shadow);
}
.site-nav a { display: block; padding: 12px 14px; border-radius: 14px; color: #344054; font-weight: 700; font-size: 15px; }
.site-nav a:hover, .site-nav a.active { color: var(--blue); background: #F0F6FF; }
.nav-toggle { position: absolute; opacity: 0; pointer-events: none; }
.nav-toggle-label {
    width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 14px; display: inline-flex;
    flex-direction: column; justify-content: center; gap: 5px; padding: 0 11px; background: #fff;
}
.nav-toggle-label span { display: block; height: 2px; background: #23304A; border-radius: 999px; }
.nav-toggle:checked ~ .site-nav { display: block; }
.download-btn {
    display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 0 24px;
    border-radius: 999px; background: var(--blue); color: #fff; font-weight: 800; letter-spacing: 0.02em;
    box-shadow: 0 12px 24px rgba(41, 128, 254, 0.24); transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}
.download-btn:hover { background: var(--blue-hover); transform: translateY(-2px); box-shadow: 0 16px 30px rgba(23, 104, 232, 0.28); }
.vpn-lab-hero {
    position: relative; padding: 72px 0 56px; background: var(--gradient); color: #fff; overflow: hidden;
}
.vpn-lab-hero::before, .cta-section::before {
    content: ""; position: absolute; inset: 0;
    background: radial-gradient(circle at 12% 20%, rgba(255,255,255,.18), transparent 28%),
    radial-gradient(circle at 82% 34%, rgba(255,255,255,.18), transparent 30%),
    linear-gradient(180deg, rgba(255,255,255,.10), transparent); pointer-events: none;
}
.hero-grid { position: relative; display: grid; gap: 38px; align-items: center; }
.hero-copy h1, .hero-copy p { color: #fff; }
.hero-copy p { max-width: 640px; color: rgba(255,255,255,.88); font-size: 18px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; margin: 28px 0; }
.hero-note { color: rgba(255,255,255,.78); font-size: 14px; }
.hero-tags, .lab-tags, .inline-tags { display: flex; flex-wrap: wrap; gap: 10px; }
.hero-tags span, .lab-tags span, .inline-tags span {
    display: inline-flex; align-items: center; padding: 8px 12px; border-radius: 999px; color: rgba(255,255,255,.94);
    background: rgba(255,255,255,.14); border: 1px solid rgba(255,255,255,.26); font-weight: 700; font-size: 14px;
}
.lab-visual { position: relative; min-height: 420px; display: grid; place-items: center; }
.hero-device-card {
    position: relative; width: min(420px, 88vw); padding: 22px; border-radius: 36px; background: rgba(255,255,255,.18);
    border: 1px solid rgba(255,255,255,.28); box-shadow: 0 30px 80px rgba(13, 28, 82, .24); backdrop-filter: blur(18px);
}
.hero-device-card img { width: 100%; border-radius: 26px; background: #fff; }
.float-card {
    position: absolute; display: inline-flex; align-items: center; gap: 8px; padding: 12px 14px; border-radius: 18px;
    color: #17203A; background: rgba(255,255,255,.92); border: 1px solid rgba(255,255,255,.60);
    box-shadow: 0 18px 40px rgba(20, 38, 90, .18); font-weight: 800; font-size: 14px;
}
.float-card.one { top: 12px; left: 0; }
.float-card.two { top: 88px; right: 0; }
.float-card.three { bottom: 84px; left: 8px; }
.float-card.four { bottom: 18px; right: 14px; }
.privacy-summary { margin-top: -32px; position: relative; z-index: 3; }
.summary-grid { display: grid; gap: 18px; }
.summary-card, .security-card, .info-card, .risk-card, .faq-item, .step-card, .download-step, .page-card {
    background: #fff; border: 1px solid var(--line); border-radius: var(--radius-md); box-shadow: 0 12px 32px rgba(26, 44, 94, 0.06);
}
.summary-card { padding: 24px; }
.summary-card small { display: inline-block; color: var(--blue); font-weight: 800; margin-bottom: 10px; }
.text-link { color: var(--blue); font-weight: 800; }
.feature-split, .vpn-connection-section, .global-nodes-section, .high-speed-section, .multi-device-section { display: grid; gap: 32px; align-items: center; }
.feature-media {
    padding: 20px; border-radius: var(--radius-lg); background: linear-gradient(180deg, #fff, #F5F8FF);
    border: 1px solid var(--line); box-shadow: var(--shadow);
}
.feature-media img { width: 100%; border-radius: 26px; background: #fff; }
.feature-list, .clean-list { display: grid; gap: 12px; margin: 22px 0; padding: 0; list-style: none; }
.feature-list li, .clean-list li { position: relative; padding-left: 28px; color: #465166; }
.feature-list li::before, .clean-list li::before {
    content: ""; position: absolute; left: 0; top: 12px; width: 10px; height: 10px; border-radius: 50%;
    background: var(--blue); box-shadow: 0 0 0 5px #E9F2FF;
}
.privacy-protection-section { display: grid; gap: 26px; align-items: start; }
.safety-panel { padding: 26px; border-radius: var(--radius-lg); background: #fff; border: 1px solid var(--line); box-shadow: var(--shadow); }
.safety-panel .panel-row { display: grid; gap: 14px; }
.panel-chip { display: inline-flex; width: fit-content; padding: 8px 12px; border-radius: 999px; color: var(--blue); background: #EDF5FF; font-weight: 800; margin-bottom: 8px; }
.no-log-policy-section { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 28px; box-shadow: var(--shadow); }
.no-log-grid, .protocol-grid, .risk-grid, .page-grid { display: grid; gap: 18px; }
.security-card, .info-card, .risk-card, .step-card, .page-card { padding: 22px; }
.security-card { border-left: 4px solid var(--blue); }
.high-speed-section { padding: 30px; border-radius: var(--radius-lg); background: #F2F6FF; border: 1px solid #DDE8FF; }
.multi-device-cards { display: grid; gap: 14px; }
.device-pill { padding: 18px; border-radius: 20px; background: #fff; border: 1px solid var(--line); }
.encryption-protocol-section { padding: 28px; border-radius: var(--radius-lg); background: #111A35; color: #fff; overflow: hidden; position: relative; }
.encryption-protocol-section h2, .encryption-protocol-section h3 { color: #fff; }
.encryption-protocol-section p, .encryption-protocol-section li { color: rgba(255,255,255,.75); }
.encryption-protocol-section .text-link { color: #9CC4FF; }
.protocol-card { padding: 22px; border-radius: 24px; background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.16); }
.process-steps { display: grid; gap: 16px; counter-reset: step; }
.step-card { position: relative; padding-left: 70px; }
.step-card::before {
    counter-increment: step; content: counter(step); position: absolute; left: 22px; top: 22px; width: 34px; height: 34px;
    border-radius: 12px; display: grid; place-items: center; color: #fff; background: var(--blue); font-weight: 900;
}
.risk-card { border-top: 4px solid var(--blue); }
.risk-card strong { display: block; margin: 10px 0 6px; }
.faq-list { display: grid; gap: 14px; }
.faq-item { padding: 22px; }
.faq-item h3 { font-size: 18px; margin-bottom: 8px; }
.cta-section { position: relative; padding: 64px 0; background: var(--gradient); color: #fff; text-align: center; overflow: hidden; }
.cta-section h2, .cta-section p { color: #fff; }
.cta-inner { position: relative; width: min(780px, calc(100% - 32px)); margin: 0 auto; }
.page-hero {
    padding: 56px 0 34px; background: radial-gradient(circle at 8% 0%, rgba(53,88,242,.10), transparent 28%),
    radial-gradient(circle at 88% 16%, rgba(184,77,218,.10), transparent 32%), #fff; border-bottom: 1px solid var(--line);
}
.page-hero p { max-width: 780px; font-size: 18px; }
.page-layout { display: grid; gap: 28px; align-items: start; }
.article-panel { padding: 26px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg); box-shadow: var(--shadow); }
.article-panel p { color: #4D5A70; }
.aside-panel { padding: 22px; background: #F5F8FF; border: 1px solid #DFE9FF; border-radius: 24px; }
.aside-panel a { display: block; color: var(--blue); font-weight: 800; margin-top: 10px; }
.checklist { display: grid; gap: 12px; margin: 20px 0; padding: 0; list-style: none; }
.checklist li { padding: 14px 16px; border-radius: 16px; background: #F7F9FD; border: 1px solid var(--line); color: #465166; }
.download-panel { margin-top: 24px; padding: 24px; border-radius: 24px; background: #F6F9FF; border: 1px solid #DDE8FF; }
.download-steps { display: grid; gap: 14px; margin: 24px 0; }
.download-step { padding: 18px; }
.site-footer { background: #F1F4FA; border-top: 1px solid var(--line); padding-top: 54px; }
.footer-grid { display: grid; gap: 26px; }
.footer-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.footer-brand img { width: 36px; height: 36px; border-radius: 12px; object-fit: cover; }
.site-footer h3 { font-size: 17px; }
.site-footer a { display: block; color: #4D5A70; margin: 8px 0; }
.site-footer a:hover { color: var(--blue); }
.footer-bottom { margin-top: 34px; padding: 18px 0; border-top: 1px solid #DDE3EF; text-align: center; }
.footer-bottom p { margin: 0; font-size: 14px; }
@media (min-width: 760px) {
    .summary-grid, .no-log-grid, .protocol-grid, .page-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .risk-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .process-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .download-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .footer-grid { grid-template-columns: 1.4fr 1fr 1fr 1fr; }
}
@media (min-width: 980px) {
    .site-nav { position: static; display: flex; align-items: center; justify-content: flex-end; gap: 4px; padding: 0; border: 0; background: transparent; box-shadow: none; }
    .site-nav a { display: inline-flex; padding: 10px 12px; font-size: 14px; }
    .nav-toggle-label { display: none; }
    .vpn-lab-hero { padding: 92px 0 84px; }
    .hero-grid { grid-template-columns: 1.05fr .95fr; }
    .feature-split, .vpn-connection-section, .global-nodes-section, .high-speed-section, .multi-device-section { grid-template-columns: 1fr 1fr; }
    .feature-split.reverse .feature-media, .high-speed-section .feature-media { order: 2; }
    .privacy-protection-section { grid-template-columns: .82fr 1.18fr; }
    .safety-panel .panel-row { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .risk-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
    .process-steps { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .page-layout { grid-template-columns: minmax(0, 1fr) 320px; }
    .article-panel { padding: 36px; }
    .section { padding: 92px 0; }
}
@media (max-width: 520px) {
    .container { width: min(100% - 24px, 1120px); }
    .site-nav { left: 12px; right: 12px; }
    .vpn-lab-hero { padding: 52px 0 48px; }
    .hero-actions { align-items: stretch; }
    .download-btn { width: 100%; min-height: 52px; }
    .lab-visual { min-height: 360px; }
    .float-card { font-size: 12px; padding: 10px 11px; }
    .section { padding: 56px 0; }
    .high-speed-section, .encryption-protocol-section, .no-log-policy-section { padding: 22px; }
}