:root {
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #1f2937;
    --muted: #667085;
    --line: #e5e7eb;
    --soft: #f5f7fb;
    --soft-blue: #eef5ff;
    --white: #ffffff;
    --radius: 24px;
    --shadow: 0 18px 50px rgba(31, 41, 55, 0.08);
}
* { 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: #ffffff;
    line-height: 1.7;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
.container { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.narrow { width: min(880px, calc(100% - 32px)); margin: 0 auto; }
.section { padding: 56px 0; }
.section-title { margin: 0 0 14px; font-size: clamp(28px, 5vw, 42px); line-height: 1.2; }
.section-desc { margin: 0 0 28px; color: var(--muted); max-width: 760px; }
.site-header { position: sticky; top: 0; z-index: 20; background: rgba(255,255,255,.94); backdrop-filter: blur(18px); border-bottom: 1px solid rgba(229,231,235,.9); }
.nav-shell { 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; letter-spacing: -.02em; }
.brand img { width: 38px; height: 38px; border-radius: 12px; object-fit: cover; background: var(--soft); }
.site-nav { display: none; position: absolute; left: 14px; right: 14px; top: 72px; background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 12px; box-shadow: var(--shadow); }
.site-nav a { display: block; padding: 12px 14px; color: var(--muted); border-radius: 14px; font-weight: 650; }
.site-nav a.active, .site-nav a:hover { color: var(--blue); background: var(--soft-blue); }
.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: grid; place-content: center; gap: 5px; cursor: pointer; }
.nav-toggle-label span { display: block; width: 20px; height: 2px; background: var(--text); border-radius: 2px; }
.nav-toggle:checked ~ .site-nav { display: block; }
.download-btn { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 13px 24px; background: var(--blue); color: #fff; border-radius: 999px; font-weight: 800; box-shadow: 0 12px 30px 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 18px 38px rgba(23,104,232,.32); }
.vpn-dashboard-hero { background: var(--gradient); color: #fff; padding: 54px 0 68px; position: relative; overflow: hidden; }
.vpn-dashboard-hero:before, .vpn-dashboard-hero:after { content: ""; position: absolute; border-radius: 50%; background: rgba(255,255,255,.12); filter: blur(2px); }
.vpn-dashboard-hero:before { width: 360px; height: 360px; right: -160px; top: -110px; }
.vpn-dashboard-hero:after { width: 240px; height: 240px; left: -120px; bottom: -80px; }
.hero-grid { position: relative; z-index: 1; display: grid; gap: 32px; align-items: center; }
.hero-copy h1 { margin: 0 0 18px; font-size: clamp(36px, 8vw, 64px); line-height: 1.08; letter-spacing: -.04em; }
.hero-copy p { margin: 0 0 24px; color: rgba(255,255,255,.86); font-size: 18px; max-width: 650px; }
.hero-tags, .tag-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.hero-tags span, .tag-row span, .category-badge { display: inline-flex; align-items: center; border-radius: 999px; padding: 7px 12px; font-size: 13px; font-weight: 700; }
.hero-tags span { background: rgba(255,255,255,.14); border: 1px solid rgba(255,255,255,.22); }
.category-badge { background: var(--soft-blue); color: var(--blue); margin-bottom: 14px; }
.dashboard-card { background: rgba(255,255,255,.16); border: 1px solid rgba(255,255,255,.22); border-radius: 30px; padding: 18px; box-shadow: 0 24px 80px rgba(17,24,39,.18); backdrop-filter: blur(12px); }
.dashboard-visual { position: relative; display: grid; gap: 14px; }
.product-panel { background: #fff; border-radius: 26px; padding: 18px; box-shadow: var(--shadow); }
.status-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.status-card { background: rgba(255,255,255,.9); color: var(--text); border-radius: 18px; padding: 14px; min-height: 94px; }
.status-card strong { display: block; font-size: 14px; }
.status-card small { color: var(--muted); }
.service-index { margin-top: -32px; position: relative; z-index: 2; }
.service-index-panel { background: #fff; border: 1px solid var(--line); border-radius: 30px; box-shadow: var(--shadow); padding: 24px; }
.service-index h2 { margin: 0 0 6px; font-size: clamp(26px, 5vw, 38px); }
.service-grid, .category-grid { display: grid; gap: 16px; }
.service-card { background: #fff; border: 1px solid var(--line); border-radius: 22px; padding: 20px; transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease; }
.service-card:hover { transform: translateY(-3px); border-color: rgba(41,128,254,.35); box-shadow: var(--shadow); }
.service-label { display: inline-flex; align-items: center; color: var(--blue); background: var(--soft-blue); border-radius: 999px; padding: 4px 10px; font-weight: 800; font-size: 12px; margin-bottom: 10px; }
.service-card h3 { margin: 0 0 8px; font-size: 20px; }
.service-card p { margin: 0 0 12px; color: var(--muted); }
.link-more { color: var(--blue); font-weight: 800; }
.feature-block { display: grid; gap: 24px; align-items: center; background: #fff; border: 1px solid var(--line); border-radius: 30px; padding: 22px; box-shadow: var(--shadow); }
.feature-block.reverse { background: var(--soft); }
.feature-copy h2 { margin: 0 0 12px; font-size: clamp(26px, 5vw, 40px); line-height: 1.2; }
.feature-copy p { margin: 0 0 16px; color: var(--muted); }
.feature-list { display: grid; gap: 10px; margin: 0 0 16px; padding: 0; list-style: none; }
.feature-list li { position: relative; padding-left: 22px; color: #344054; }
.feature-list li:before { content: ""; position: absolute; left: 0; top: 12px; width: 8px; height: 8px; border-radius: 50%; background: var(--blue); }
.feature-image { background: linear-gradient(180deg, #f6f9ff, #fff); border: 1px solid var(--line); border-radius: 26px; padding: 18px; }
.light-section { background: var(--soft); }
.privacy-protection-section, .no-log-policy-section, .encryption-protocol-section { background: #fff; }
.safety-panel { display: grid; gap: 16px; background: linear-gradient(180deg, #f8fbff, #fff); border: 1px solid var(--line); border-radius: 30px; padding: 24px; }
.panel-items { display: grid; gap: 14px; }
.panel-item { border-left: 4px solid var(--blue); background: #fff; border-radius: 18px; padding: 16px; box-shadow: 0 10px 24px rgba(31,41,55,.05); }
.panel-item strong { display: block; margin-bottom: 4px; }
.panel-item p { margin: 0; color: var(--muted); }
.device-grid { display: grid; gap: 16px; }
.device-card { background: #fff; border: 1px solid var(--line); border-radius: 24px; padding: 20px; }
.device-card h3 { margin: 0 0 8px; }
.device-card p { color: var(--muted); margin: 0; }
.tech-panel { background: #111827; color: #fff; border-radius: 28px; padding: 24px; }
.tech-panel p { color: rgba(255,255,255,.74); }
.protocol-lines { display: grid; gap: 10px; margin-top: 18px; }
.protocol-line { display: flex; justify-content: space-between; gap: 12px; padding: 12px 0; border-bottom: 1px solid rgba(255,255,255,.12); }
.process-steps { display: grid; gap: 14px; }
.step-card { background: #fff; border: 1px solid var(--line); border-radius: 22px; padding: 18px; }
.step-num { width: 36px; height: 36px; border-radius: 50%; background: var(--blue); color: #fff; display: grid; place-items: center; font-weight: 900; margin-bottom: 12px; }
.step-card h3 { margin: 0 0 8px; }
.step-card p { margin: 0 0 10px; color: var(--muted); }
.risk-grid { display: grid; gap: 16px; }
.risk-card { background: #fff; border: 1px solid var(--line); border-top: 4px solid var(--blue); border-radius: 22px; padding: 18px; }
.risk-card h3 { margin: 0 0 8px; }
.risk-card p { margin: 0 0 10px; color: var(--muted); }
.faq-list { display: grid; gap: 14px; }
.faq-item { background: #fff; border: 1px solid var(--line); border-radius: 22px; padding: 18px; }
.faq-item h3 { margin: 0 0 8px; font-size: 18px; }
.faq-item p { margin: 0; color: var(--muted); }
.cta-section { padding: 56px 0; background: var(--gradient); color: #fff; text-align: center; }
.cta-card { width: min(760px, calc(100% - 32px)); margin: 0 auto; }
.cta-card h2 { margin: 0 0 12px; font-size: clamp(28px, 5vw, 42px); }
.cta-card p { color: rgba(255,255,255,.84); margin: 0 0 24px; }
.page-hero { padding: 48px 0 28px; background: linear-gradient(180deg, #f7faff 0%, #fff 100%); }
.page-hero h1 { margin: 0 0 14px; font-size: clamp(34px, 7vw, 54px); line-height: 1.12; letter-spacing: -.03em; }
.page-hero p { margin: 0; color: var(--muted); font-size: 18px; }
.content-layout { display: grid; gap: 24px; align-items: start; }
.content-card { background: #fff; border: 1px solid var(--line); border-radius: 26px; padding: 22px; box-shadow: 0 12px 36px rgba(31,41,55,.05); }
.content-card h2 { margin: 0 0 12px; font-size: 26px; }
.content-card h3 { margin: 18px 0 8px; }
.content-card p { color: var(--muted); }
.content-card ul, .content-card ol { padding-left: 22px; color: #344054; }
.side-panel { background: var(--soft-blue); border: 1px solid #dbeafe; border-radius: 26px; padding: 20px; }
.side-panel h3 { margin: 0 0 10px; }
.side-panel a { display: block; color: var(--blue); font-weight: 800; margin: 10px 0; }
.checklist { display: grid; gap: 12px; margin: 18px 0; }
.check-item { background: var(--soft); border: 1px solid var(--line); border-radius: 18px; padding: 14px; }
.download-zone { margin-top: 22px; }
.install-steps { counter-reset: install; display: grid; gap: 12px; margin: 18px 0; }
.install-step { position: relative; padding: 16px 16px 16px 56px; border: 1px solid var(--line); border-radius: 18px; background: #fff; }
.install-step:before { counter-increment: install; content: counter(install); position: absolute; left: 16px; top: 17px; width: 28px; height: 28px; border-radius: 50%; background: var(--blue); color: #fff; display: grid; place-items: center; font-weight: 900; }
.about-band { background: var(--soft); border-radius: 30px; padding: 24px; }
.site-footer { background: #101828; color: #fff; padding: 42px 0 22px; }
.footer-grid { display: grid; gap: 28px; }
.footer-brand { font-size: 22px; font-weight: 900; margin-bottom: 12px; }
.site-footer p { color: rgba(255,255,255,.68); margin: 0; }
.site-footer h3 { margin: 0 0 12px; }
.site-footer a { display: block; color: rgba(255,255,255,.72); margin: 8px 0; }
.site-footer a:hover { color: #fff; }
.footer-bottom { width: min(1120px, calc(100% - 32px)); margin: 28px auto 0; padding-top: 18px; border-top: 1px solid rgba(255,255,255,.12); color: rgba(255,255,255,.6); font-size: 14px; }
@media (min-width: 640px) {
    .service-grid, .category-grid, .device-grid, .process-steps, .risk-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .panel-items { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}
@media (min-width: 880px) {
    .site-nav { display: flex; position: static; padding: 0; border: 0; box-shadow: none; background: transparent; gap: 4px; }
    .site-nav a { padding: 9px 12px; font-size: 14px; }
    .nav-toggle-label { display: none; }
    .hero-grid { grid-template-columns: 1.02fr .98fr; gap: 46px; }
    .service-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
    .service-grid .wide { grid-column: span 2; }
    .feature-block { grid-template-columns: 1fr 1fr; padding: 30px; }
    .feature-block.reverse .feature-image { order: -1; }
    .safety-panel { grid-template-columns: .9fr 1.1fr; padding: 30px; }
    .device-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .process-steps { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .risk-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
    .content-layout { grid-template-columns: minmax(0, 1fr) 300px; }
    .footer-grid { grid-template-columns: 1.4fr .8fr .8fr; }
}
@media (min-width: 1080px) {
    .section { padding: 76px 0; }
    .vpn-dashboard-hero { padding: 78px 0 98px; }
    .service-index-panel { padding: 30px; }
}