/* Base */
:root {
    --brand-gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-hover: #1768E8;
    --text: #182033;
    --muted: #687084;
    --light: #F6F8FC;
    --line: #E5EAF3;
    --white: #FFFFFF;
    --deep: #111827;
    --shadow: 0 18px 50px rgba(22, 35, 80, .10);
    --radius-xl: 32px;
    --radius-lg: 24px;
    --radius-md: 18px;
}
* { 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-soft { background: var(--light); }
.eyebrow, .badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 12px;
    border-radius: 999px;
    background: rgba(41, 128, 254, .10);
    color: var(--blue);
    font-size: 13px;
    font-weight: 700;
}
.section-title { margin: 14px 0 12px; font-size: clamp(28px, 4vw, 44px); line-height: 1.18; letter-spacing: -.04em; }
.section-desc { color: var(--muted); margin: 0; max-width: 760px; }
.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 28px rgba(41, 128, 254, .24);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}
.download-btn:hover { background: var(--blue-hover); transform: translateY(-2px); box-shadow: 0 16px 34px rgba(23, 104, 232, .28); }
.text-link { color: var(--blue); font-weight: 700; }
.text-link:hover { text-decoration: underline; }

/* header / responsive nav / mobile nav / desktop nav */
.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255, 255, 255, .92);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(229, 234, 243, .86);
}
.nav-wrap { min-height: 68px; display: flex; align-items: center; justify-content: space-between; gap: 18px; position: relative; }
.logo, .footer-logo { display: inline-flex; align-items: center; gap: 10px; font-weight: 900; color: var(--deep); }
.logo img, .footer-logo img { width: 38px; height: 38px; border-radius: 12px; object-fit: cover; }
.nav-toggle { position: absolute; opacity: 0; pointer-events: none; }
.nav-toggle-label {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 40px;
    padding: 8px 14px;
    border: 1px solid var(--line);
    border-radius: 999px;
    color: var(--text);
    font-weight: 700;
    cursor: pointer;
}
.site-nav {
    position: absolute;
    top: 62px;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    gap: 6px;
    padding: 14px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 20px;
    box-shadow: var(--shadow);
}
.nav-toggle:checked ~ .site-nav { display: flex; }
.site-nav a { padding: 10px 12px; border-radius: 14px; color: #4B5567; font-size: 15px; font-weight: 700; }
.site-nav a:hover, .site-nav a.active { color: var(--blue); background: rgba(41, 128, 254, .08); }

/* vpn saas hero / gradient background */
.vpn-saas-hero { padding: 34px 0 66px; background: radial-gradient(circle at 10% 10%, rgba(41,128,254,.10), transparent 30%), #fff; }
.hero-card {
    position: relative;
    overflow: hidden;
    min-height: 610px;
    border-radius: 0 0 42px 42px;
    background: var(--brand-gradient);
    color: #fff;
}
.hero-card::after {
    content: "";
    position: absolute;
    inset: auto -10% -32% -10%;
    height: 46%;
    background: #fff;
    transform: skewY(-5deg);
    transform-origin: left top;
}
.hero-inner { position: relative; z-index: 2; display: grid; gap: 34px; padding: 52px 0 112px; }
.hero-copy h1 { margin: 16px 0 18px; font-size: clamp(36px, 8vw, 68px); line-height: 1.04; letter-spacing: -.06em; }
.hero-copy p { max-width: 640px; margin: 0 0 24px; color: rgba(255,255,255,.88); font-size: 17px; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 16px; margin: 24px 0; }
.hero-note { color: rgba(255,255,255,.78); font-size: 14px; }
.security-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.security-tags span { padding: 8px 12px; border-radius: 999px; background: rgba(255,255,255,.14); border: 1px solid rgba(255,255,255,.24); color: #fff; font-weight: 700; font-size: 13px; }
.hero-visual { position: relative; min-height: 360px; display: grid; place-items: center; }
.hero-device {
    position: relative;
    width: min(420px, 86vw);
    padding: 18px;
    border-radius: 34px;
    background: rgba(255,255,255,.18);
    border: 1px solid rgba(255,255,255,.22);
    box-shadow: 0 28px 60px rgba(20, 32, 88, .28);
}
.hero-device img { border-radius: 26px; width: 100%; object-fit: cover; }
.float-card {
    position: absolute;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    border-radius: 16px;
    background: rgba(255,255,255,.92);
    color: #24304A;
    box-shadow: 0 12px 34px rgba(21, 30, 78, .18);
    font-size: 13px;
    font-weight: 800;
}
.float-card::before { content: ""; width: 8px; height: 8px; border-radius: 999px; background: var(--blue); }
.float-card.one { top: 12px; left: 0; }
.float-card.two { top: 70px; right: 0; }
.float-card.three { bottom: 72px; left: 2px; }
.float-card.four { bottom: 18px; right: 16px; }

/* product highlights / highlight card */
.product-highlights { margin-top: -62px; position: relative; z-index: 5; }
.highlight-grid { display: grid; gap: 16px; }
.highlight-card, .info-card, .risk-card, .faq-item, .step-card {
    background: var(--white);
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    box-shadow: 0 12px 34px rgba(22, 35, 80, .06);
}
.highlight-card { padding: 24px; }
.highlight-label { color: var(--blue); font-size: 13px; font-weight: 900; }
.highlight-card h3 { margin: 8px 0 8px; font-size: 21px; }
.highlight-card p { margin: 0 0 14px; color: var(--muted); }

/* content container / module layouts */
.feature-row { display: grid; gap: 26px; align-items: center; }
.feature-panel {
    padding: 26px;
    border-radius: var(--radius-xl);
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}
.feature-panel img { border-radius: 26px; width: 100%; object-fit: cover; }
.feature-points { display: grid; gap: 12px; margin-top: 20px; }
.feature-point { padding: 14px 16px; border-radius: 18px; background: var(--light); color: #4B5567; }
.feature-point strong { color: var(--text); }
.vpn-connection-section, .high-speed-section, .global-nodes-section, .privacy-protection-section, .no-log-policy-section, .multi-device-section, .encryption-protocol-section { position: relative; }
.high-speed-section { background: linear-gradient(180deg, #F7FAFF 0%, #FFFFFF 100%); }
.speed-board, .tech-board {
    display: grid;
    gap: 16px;
    padding: 22px;
    border-radius: var(--radius-xl);
    background: linear-gradient(180deg, #fff 0%, #F7FAFF 100%);
    border: 1px solid var(--line);
}
.metric-card { padding: 18px; border-radius: 22px; background: #fff; border: 1px solid var(--line); }
.metric-card span { display: block; color: var(--blue); font-weight: 900; font-size: 13px; margin-bottom: 7px; }
.metric-card p { margin: 0; color: var(--muted); }
.privacy-grid, .policy-grid, .device-grid, .tech-grid { display: grid; gap: 16px; margin-top: 24px; }
.info-card { padding: 22px; }
.info-card h3 { margin: 0 0 8px; }
.info-card p { margin: 0; color: var(--muted); }
.privacy-layout { display: grid; gap: 22px; align-items: center; }
.privacy-image { padding: 18px; border-radius: var(--radius-xl); background: #fff; border: 1px solid var(--line); box-shadow: var(--shadow); }
.privacy-image img { border-radius: 24px; }
.gradient-panel { background: var(--brand-gradient); color: #fff; border-radius: var(--radius-xl); padding: 28px; overflow: hidden; }
.gradient-panel p { color: rgba(255,255,255,.86); }
.gradient-panel .text-link { color: #fff; text-decoration: underline; }

/* process steps */
.process-steps { display: grid; gap: 16px; margin-top: 28px; }
.step-card { padding: 22px; position: relative; overflow: hidden; }
.step-num { display: inline-grid; place-items: center; width: 38px; height: 38px; border-radius: 14px; background: rgba(41,128,254,.10); color: var(--blue); font-weight: 900; margin-bottom: 12px; }
.step-card h3 { margin: 0 0 8px; }
.step-card p { margin: 0 0 12px; color: var(--muted); }

/* safety panel / risk grid */
.safety-panel { padding: 26px; border-radius: var(--radius-xl); background: #fff; border: 1px solid var(--line); box-shadow: var(--shadow); }
.risk-grid { display: grid; gap: 16px; margin-top: 24px; }
.risk-card { padding: 20px; border-left: 4px solid var(--blue); }
.risk-card h3 { margin: 0 0 8px; }
.risk-card p { margin: 0 0 10px; color: var(--muted); }
.risk-card strong { display: block; color: var(--text); margin-bottom: 4px; }

/* FAQ item */
.faq-list { display: grid; gap: 14px; margin-top: 26px; }
.faq-item { padding: 22px; }
.faq-item h3 { margin: 0 0 8px; font-size: 19px; }
.faq-item p { margin: 0; color: var(--muted); }
.faq-grid { display: grid; gap: 16px; }

/* CTA */
.cta-section { padding: 64px 0; }
.cta-card { text-align: center; border-radius: var(--radius-xl); padding: 46px 24px; background: var(--brand-gradient); color: #fff; overflow: hidden; }
.cta-card h2 { margin: 0 0 12px; font-size: clamp(28px, 5vw, 44px); letter-spacing: -.04em; }
.cta-card p { margin: 0 auto 22px; max-width: 720px; color: rgba(255,255,255,.86); }

/* Inner pages */
.page-hero { padding: 54px 0 32px; background: linear-gradient(180deg, #F7FAFF 0%, #fff 100%); }
.page-hero h1 { margin: 16px 0 14px; font-size: clamp(34px, 6vw, 58px); line-height: 1.12; letter-spacing: -.05em; }
.page-hero p { margin: 0; max-width: 780px; color: var(--muted); font-size: 17px; }
.content-layout { display: grid; gap: 24px; padding: 34px 0 70px; }
.article-card { padding: 24px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius-xl); box-shadow: var(--shadow); }
.article-card h2 { margin: 0 0 12px; font-size: 25px; }
.article-card p { color: var(--muted); margin: 0 0 16px; }
.article-card p:last-child { margin-bottom: 0; }
.check-list, .plain-list { display: grid; gap: 12px; padding: 0; margin: 18px 0 0; list-style: none; }
.check-list li, .plain-list li { padding: 14px 16px; border-radius: 18px; background: var(--light); color: #4B5567; }
.check-list li strong, .plain-list li strong { color: var(--text); }
.side-panel { display: grid; gap: 16px; align-content: start; }
.side-card { padding: 20px; border-radius: 24px; border: 1px solid var(--line); background: #fff; box-shadow: 0 12px 34px rgba(22,35,80,.06); }
.side-card h3 { margin: 0 0 10px; }
.side-card a { display: block; color: var(--blue); font-weight: 700; padding: 6px 0; }
.page-download { margin-top: 24px; }
.download-only-panel { text-align: center; max-width: 820px; margin: 0 auto; }
.download-steps { counter-reset: step; display: grid; gap: 14px; margin-top: 26px; }
.download-steps li { list-style: none; text-align: left; padding: 18px; border-radius: 20px; background: #fff; border: 1px solid var(--line); box-shadow: 0 12px 34px rgba(22,35,80,.06); }
.download-steps li::before { counter-increment: step; content: counter(step); display: inline-grid; place-items: center; width: 32px; height: 32px; margin-right: 10px; border-radius: 12px; background: rgba(41,128,254,.10); color: var(--blue); font-weight: 900; }
.about-grid { display: grid; gap: 16px; margin-top: 22px; }

/* footer */
.site-footer { background: #111827; color: rgba(255,255,255,.78); padding: 48px 0 22px; }
.footer-grid { display: grid; gap: 28px; }
.footer-logo { color: #fff; margin-bottom: 12px; }
.site-footer h3 { color: #fff; margin: 0 0 12px; font-size: 16px; }
.site-footer a { display: block; color: rgba(255,255,255,.72); margin: 7px 0; }
.site-footer a:hover { color: #fff; }
.site-footer p { margin: 0; max-width: 420px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.12); margin-top: 32px; padding-top: 20px; font-size: 14px; }

@media (min-width: 680px) {
    .highlight-grid, .privacy-grid, .policy-grid, .device-grid, .tech-grid, .about-grid { grid-template-columns: repeat(2, 1fr); }
    .process-steps { grid-template-columns: repeat(2, 1fr); }
    .risk-grid { grid-template-columns: repeat(2, 1fr); }
    .faq-grid { grid-template-columns: repeat(2, 1fr); }
    .download-steps { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
    .nav-toggle-label { display: none; }
    .site-nav { position: static; display: flex; flex-direction: row; align-items: center; gap: 4px; padding: 0; border: 0; box-shadow: none; background: transparent; }
    .site-nav a { font-size: 14px; padding: 8px 10px; }
    .hero-inner { grid-template-columns: 1.02fr .98fr; align-items: center; padding: 76px 0 132px; }
    .hero-visual { min-height: 470px; }
    .feature-row, .privacy-layout, .content-layout { grid-template-columns: 1.05fr .95fr; }
    .feature-row.reverse > :first-child { order: 2; }
    .highlight-grid { grid-template-columns: repeat(4, 1fr); }
    .policy-grid, .device-grid, .tech-grid { grid-template-columns: repeat(3, 1fr); }
    .process-steps { grid-template-columns: repeat(3, 1fr); }
    .risk-grid { grid-template-columns: repeat(4, 1fr); }
    .footer-grid { grid-template-columns: 1.4fr 1fr 1fr 1fr; }
    .section { padding: 78px 0; }
}
@media (min-width: 1100px) {
    .site-nav a { padding: 8px 12px; }
    .risk-grid { grid-template-columns: repeat(4, 1fr); }
}