:root {
    --brand-gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #202638;
    --muted: #667085;
    --soft: #F5F7FB;
    --soft-blue: #EEF5FF;
    --line: #E6EAF2;
    --card: #FFFFFF;
    --shadow: 0 18px 55px rgba(30, 62, 120, .10);
    --radius: 28px;
}
* { 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; }
.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255,255,255,.94);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(230,234,242,.85);
}
.header-inner {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.logo, .footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #18233D;
    letter-spacing: .02em;
    white-space: nowrap;
}
.logo img, .footer-logo img {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    object-fit: cover;
}
.site-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 4px;
    font-size: 14px;
}
.site-nav a {
    color: #48546A;
    padding: 8px 10px;
    border-radius: 999px;
}
.site-nav a:hover, .site-nav a.active {
    color: var(--blue);
    background: #EEF5FF;
}
.container {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
}
.section {
    padding: 64px 0;
}
.section-tight { padding: 42px 0; }
.section-head {
    max-width: 720px;
    margin: 0 auto 28px;
    text-align: center;
}
.section-kicker, .badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--blue);
    background: #EEF5FF;
    border: 1px solid #D8E8FF;
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 700;
}
h1, h2, h3 { line-height: 1.18; margin: 0 0 14px; color: #172033; }
h1 { font-size: clamp(34px, 8vw, 62px); letter-spacing: -.05em; }
h2 { font-size: clamp(28px, 5vw, 44px); letter-spacing: -.035em; }
h3 { font-size: 20px; }
p { margin: 0 0 16px; color: var(--muted); }
.lead { font-size: 18px; color: #536079; }
.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;
    box-shadow: 0 12px 26px rgba(41,128,254,.22);
    transition: transform .18s ease, background .18s ease, box-shadow .18s ease;
}
.download-btn:hover {
    background: var(--blue-dark);
    transform: translateY(-2px);
    box-shadow: 0 16px 34px rgba(23,104,232,.26);
}
.link-more {
    display: inline-flex;
    align-items: center;
    color: var(--blue);
    font-weight: 800;
    margin-top: 6px;
}
.link-more::after { content: "→"; margin-left: 6px; }
.vpn-saas-hero {
    position: relative;
    padding: 42px 0 72px;
    background: linear-gradient(180deg, #F7FAFF 0%, #FFFFFF 100%);
    overflow: hidden;
}
.vpn-saas-hero::before {
    content: "";
    position: absolute;
    inset: 0 0 auto 0;
    height: 74%;
    background: var(--brand-gradient);
    clip-path: polygon(0 0, 100% 0, 100% 76%, 0 100%);
    z-index: 0;
}
.hero-inner {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1fr;
    gap: 34px;
    align-items: center;
}
.hero-copy { color: #fff; padding-top: 16px; }
.hero-copy h1, .hero-copy p { color: #fff; }
.hero-copy .lead { color: rgba(255,255,255,.90); max-width: 690px; }
.hero-actions { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; margin-top: 26px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 24px; }
.hero-tags span {
    color: #fff;
    border: 1px solid rgba(255,255,255,.35);
    background: rgba(255,255,255,.14);
    border-radius: 999px;
    padding: 7px 12px;
    font-size: 13px;
}
.hero-visual {
    position: relative;
    min-height: 360px;
    border-radius: 36px;
    padding: 18px;
    background: rgba(255,255,255,.16);
    box-shadow: var(--shadow);
}
.hero-visual .product-shell {
    position: relative;
    min-height: 320px;
    display: grid;
    place-items: center;
    border-radius: 30px;
    background: rgba(255,255,255,.92);
    overflow: hidden;
}
.hero-visual img { max-height: 360px; object-fit: contain; }
.float-card {
    position: absolute;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    border-radius: 18px;
    padding: 10px 12px;
    background: rgba(255,255,255,.94);
    color: #25304A;
    border: 1px solid rgba(230,234,242,.9);
    box-shadow: 0 14px 32px rgba(24,38,70,.13);
    font-size: 13px;
    font-weight: 800;
}
.float-card::before {
    content: "";
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--blue);
}
.float-card.one { left: 8px; top: 36px; }
.float-card.two { right: 8px; top: 88px; }
.float-card.three { left: 18px; bottom: 70px; }
.float-card.four { right: 16px; bottom: 28px; }
.product-highlights {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    margin-top: -42px;
    position: relative;
    z-index: 2;
}
.highlight-card, .feature-card, .info-card, .risk-card, .faq-item, .step-card, .aside-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 24px;
    box-shadow: 0 12px 36px rgba(23, 38, 70, .06);
}
.highlight-card { padding: 22px; }
.highlight-card .tag {
    display: inline-block;
    color: var(--blue);
    background: #EEF5FF;
    border-radius: 999px;
    padding: 3px 10px;
    font-size: 12px;
    font-weight: 800;
    margin-bottom: 12px;
}
.feature-split {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    align-items: center;
}
.feature-panel {
    border-radius: 32px;
    padding: 26px;
    border: 1px solid var(--line);
    background: #fff;
    box-shadow: var(--shadow);
}
.feature-panel.soft { background: linear-gradient(180deg, #F7FAFF 0%, #FFFFFF 100%); }
.feature-image {
    border-radius: 30px;
    background: var(--soft-blue);
    padding: 20px;
    overflow: hidden;
    border: 1px solid #DDEAFF;
}
.feature-list, .check-list {
    list-style: none;
    padding: 0;
    margin: 18px 0 8px;
    display: grid;
    gap: 10px;
}
.feature-list li, .check-list li {
    position: relative;
    padding-left: 24px;
    color: #4D5B73;
}
.feature-list li::before, .check-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: .72em;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--blue);
    box-shadow: 0 0 0 5px #E8F2FF;
}
.gradient-band {
    background: linear-gradient(180deg, #F7FAFF 0%, #F3F7FC 100%);
}
.speed-grid, .node-grid, .privacy-grid, .policy-grid, .device-grid, .protocol-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
}
.feature-card, .info-card { padding: 24px; }
.speed-meter {
    border-radius: 30px;
    padding: 24px;
    color: #fff;
    background: var(--brand-gradient);
    overflow: hidden;
}
.speed-meter p, .speed-meter h3 { color: #fff; }
.speed-lines { display: grid; gap: 12px; margin-top: 18px; }
.speed-lines span {
    display: block;
    height: 10px;
    border-radius: 999px;
    background: rgba(255,255,255,.34);
    overflow: hidden;
}
.speed-lines span::before {
    content: "";
    display: block;
    height: 100%;
    border-radius: inherit;
    background: rgba(255,255,255,.9);
}
.speed-lines span:nth-child(1)::before { width: 78%; }
.speed-lines span:nth-child(2)::before { width: 58%; }
.speed-lines span:nth-child(3)::before { width: 68%; }
.privacy-protection-section .privacy-grid { align-items: center; }
.privacy-tags { display: flex; flex-wrap: wrap; gap: 10px; margin: 18px 0; }
.privacy-tags span {
    background: #F2F6FF;
    color: #36517D;
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 700;
}
.process-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}
.step-card { padding: 20px; position: relative; }
.step-num {
    width: 38px;
    height: 38px;
    border-radius: 14px;
    display: inline-grid;
    place-items: center;
    color: #fff;
    background: var(--blue);
    font-weight: 900;
    margin-bottom: 12px;
}
.risk-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}
.risk-card {
    padding: 20px;
    border-left: 4px solid var(--blue);
}
.risk-card strong { display: block; margin-bottom: 6px; color: #172033; }
.faq-list { display: grid; gap: 14px; }
.faq-item { padding: 20px; }
.faq-item h3 { margin-bottom: 8px; }
.cta-section {
    text-align: center;
    color: #fff;
    background: var(--brand-gradient);
    border-radius: 36px;
    padding: 44px 22px;
    overflow: hidden;
    position: relative;
}
.cta-section h2, .cta-section p { color: #fff; }
.cta-section p { opacity: .9; max-width: 680px; margin-left: auto; margin-right: auto; }
.page-hero {
    background: linear-gradient(180deg, #F7FAFF 0%, #FFFFFF 100%);
    padding: 54px 0 30px;
}
.page-hero-inner {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    align-items: center;
}
.page-hero h1 { font-size: clamp(32px, 7vw, 52px); }
.article-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
    align-items: start;
}
.article-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 30px;
    box-shadow: var(--shadow);
    padding: 24px;
}
.article-card h2 { font-size: 26px; }
.article-card .download-wrap { margin-top: 24px; }
.tip-box {
    border-radius: 24px;
    padding: 20px;
    background: #F7FAFF;
    border: 1px solid #DDEAFF;
    margin: 18px 0;
}
.aside-card { padding: 20px; }
.aside-card a { display: block; color: var(--blue); font-weight: 800; margin-top: 10px; }
.download-steps {
    counter-reset: step;
    display: grid;
    gap: 14px;
    margin: 24px 0;
}
.download-steps li {
    list-style: none;
    padding: 18px 18px 18px 56px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 22px;
    position: relative;
}
.download-steps li::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 18px;
    top: 18px;
    width: 28px;
    height: 28px;
    border-radius: 10px;
    display: grid;
    place-items: center;
    color: #fff;
    background: var(--blue);
    font-weight: 900;
}
.site-footer {
    background: #101828;
    color: #D7DEEA;
    padding: 48px 0 24px;
    margin-top: 60px;
}
.site-footer p { color: #AEB8C8; }
.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}
.footer-logo { color: #fff; margin-bottom: 14px; }
.site-footer h3 { color: #fff; font-size: 16px; }
.site-footer a { display: block; color: #AEB8C8; margin: 8px 0; }
.site-footer a:hover { color: #fff; }
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.10);
    margin-top: 28px;
    padding-top: 18px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    color: #AEB8C8;
    font-size: 13px;
}
@media (min-width: 700px) {
    .product-highlights, .privacy-grid, .policy-grid, .device-grid, .protocol-grid, .risk-grid { grid-template-columns: repeat(2, 1fr); }
    .process-steps { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 960px) {
    .header-inner { min-height: 76px; }
    .hero-inner { grid-template-columns: minmax(0, 1.05fr) minmax(360px, .95fr); }
    .vpn-saas-hero { padding: 58px 0 92px; }
    .hero-copy { padding: 36px 0; }
    .product-highlights { grid-template-columns: repeat(4, 1fr); }
    .feature-split { grid-template-columns: repeat(2, 1fr); }
    .speed-grid, .node-grid { grid-template-columns: 1.05fr .95fr; align-items: center; }
    .privacy-protection-section .privacy-grid { grid-template-columns: 1.15fr .85fr; }
    .policy-grid, .protocol-grid { grid-template-columns: repeat(3, 1fr); }
    .device-grid { grid-template-columns: .95fr 1.05fr; align-items: center; }
    .risk-grid { grid-template-columns: repeat(4, 1fr); }
    .process-steps { grid-template-columns: repeat(3, 1fr); }
    .page-hero-inner { grid-template-columns: 1.1fr .9fr; }
    .article-layout { grid-template-columns: minmax(0, 1fr) 320px; }
    .article-card { padding: 34px; }
    .footer-grid { grid-template-columns: 1.5fr repeat(3, 1fr); }
    .footer-bottom { flex-direction: row; justify-content: space-between; }
}
@media (max-width: 760px) {
    .header-inner { align-items: flex-start; flex-direction: column; padding: 12px 0; }
    .site-nav { justify-content: flex-start; }
    .site-nav a { padding: 7px 9px; font-size: 13px; }
    .section { padding: 46px 0; }
    .hero-visual { min-height: 310px; }
    .hero-visual .product-shell { min-height: 280px; }
    .float-card { position: static; margin: 8px 8px 0 0; display: inline-flex; }
    .hero-visual { display: block; }
    .download-btn { width: 100%; }
    .hero-actions .download-btn { width: auto; min-width: 148px; }
}