:root {
    --primary: #2980FE;
    --primary-dark: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1f2937;
    --muted: #64748b;
    --light: #f5f7fb;
    --line: #e5eaf3;
    --white: #ffffff;
    --soft-blue: #eef5ff;
    --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", "Microsoft YaHei", Arial, sans-serif;
    color: var(--text);
    background: #f8fafc;
    line-height: 1.75;
    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;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(226, 232, 240, 0.9);
}

.header-inner {
    width: min(1180px, calc(100% - 28px));
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 68px;
    gap: 16px;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #172554;
    white-space: nowrap;
}

.logo img {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    object-fit: cover;
}

.nav-toggle {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.mobile-nav {
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 14px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    background: #fff;
}

.mobile-nav span {
    width: 18px;
    height: 2px;
    background: #334155;
    border-radius: 99px;
}

.desktop-nav {
    position: absolute;
    top: 68px;
    left: 14px;
    right: 14px;
    display: none;
    flex-direction: column;
    gap: 8px;
    padding: 14px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 20px;
    box-shadow: var(--shadow);
}

.nav-toggle:checked ~ .desktop-nav {
    display: flex;
}

.desktop-nav a {
    padding: 10px 12px;
    color: #475569;
    font-size: 14px;
    border-radius: 12px;
}

.desktop-nav a:hover,
.desktop-nav a.active {
    color: var(--primary);
    background: var(--soft-blue);
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 12px 24px;
    border-radius: 999px;
    background: #2980FE;
    color: #ffffff;
    font-weight: 700;
    border: 0;
    box-shadow: 0 12px 28px rgba(41, 128, 254, 0.28);
    transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.download-btn:hover {
    background: #1768E8;
    color: #ffffff;
    transform: translateY(-2px);
    box-shadow: 0 16px 36px rgba(23, 104, 232, 0.32);
}

.section {
    padding: 58px 0;
}

.section-title {
    margin: 0 0 14px;
    font-size: clamp(28px, 4vw, 42px);
    line-height: 1.2;
    letter-spacing: -0.03em;
}

.section-lead {
    margin: 0 0 24px;
    color: var(--muted);
    font-size: 16px;
}

.eyebrow,
.category-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 14px;
    padding: 6px 12px;
    border-radius: 999px;
    background: rgba(41, 128, 254, 0.1);
    color: #1768E8;
    font-weight: 700;
    font-size: 13px;
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    background: var(--gradient);
    color: #ffffff;
    padding: 74px 0 52px;
}

.vpn-network-hero::before,
.vpn-network-hero::after {
    content: "";
    position: absolute;
    inset: auto;
    border-radius: 999px;
    pointer-events: none;
}

.vpn-network-hero::before {
    width: 420px;
    height: 420px;
    right: -120px;
    top: -160px;
    background: rgba(255, 255, 255, 0.18);
    filter: blur(6px);
}

.vpn-network-hero::after {
    width: 560px;
    height: 560px;
    left: -260px;
    bottom: -260px;
    background: rgba(255, 255, 255, 0.12);
}

.hero-grid {
    position: relative;
    display: grid;
    gap: 32px;
    align-items: center;
}

.hero-copy h1 {
    margin: 0 0 18px;
    font-size: clamp(38px, 8vw, 66px);
    line-height: 1.08;
    letter-spacing: -0.05em;
}

.hero-copy p {
    margin: 0 0 24px;
    color: rgba(255, 255, 255, 0.88);
    max-width: 680px;
    font-size: 17px;
}

.hero-tags,
.status-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 18px;
}

.hero-tags span,
.status-tags span {
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.16);
    border: 1px solid rgba(255, 255, 255, 0.22);
    color: #fff;
    font-size: 13px;
}

.hero-visual {
    position: relative;
    min-height: 340px;
    padding: 18px;
    border-radius: 32px;
    background: rgba(255, 255, 255, 0.12);
    border: 1px solid rgba(255, 255, 255, 0.22);
}

.hero-visual::before {
    content: "";
    position: absolute;
    inset: 28px;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 26px;
    background-image: radial-gradient(circle at 20% 30%, rgba(255,255,255,.8) 0 3px, transparent 4px), radial-gradient(circle at 70% 22%, rgba(255,255,255,.75) 0 3px, transparent 4px), radial-gradient(circle at 52% 76%, rgba(255,255,255,.7) 0 3px, transparent 4px), linear-gradient(135deg, transparent 0 48%, rgba(255,255,255,.25) 49% 51%, transparent 52%);
}

.hero-visual img {
    position: relative;
    z-index: 2;
    margin: 16px auto 0;
    max-height: 310px;
    object-fit: contain;
    filter: drop-shadow(0 24px 36px rgba(15, 23, 42, 0.22));
}

.status-card {
    position: absolute;
    z-index: 3;
    right: 16px;
    bottom: 18px;
    max-width: 190px;
    padding: 14px;
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.94);
    color: #172554;
    box-shadow: var(--shadow);
}

.status-card strong {
    display: block;
    margin-bottom: 4px;
}

.status-card small {
    color: #64748b;
}

.node-overview {
    margin-top: -34px;
    position: relative;
    z-index: 5;
}

.node-overview-grid {
    display: grid;
    gap: 16px;
}

.node-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 24px;
    padding: 22px;
    box-shadow: var(--shadow);
}

.node-card .tag {
    display: inline-flex;
    margin-bottom: 12px;
    padding: 4px 9px;
    border-radius: 999px;
    color: #1768E8;
    background: var(--soft-blue);
    font-size: 12px;
    font-weight: 800;
}

.node-card h3,
.info-card h3,
.risk-card h3,
.faq-item h3 {
    margin: 0 0 8px;
    font-size: 19px;
}

.node-card p,
.info-card p,
.risk-card p,
.faq-item p {
    margin: 0 0 12px;
    color: var(--muted);
}

.text-link {
    color: var(--primary);
    font-weight: 700;
}

.vpn-connection-section,
.global-nodes-section,
.high-speed-section,
.privacy-protection-section,
.no-log-policy-section,
.multi-device-section,
.encryption-protocol-section {
    background: #fff;
}

.high-speed-section,
.no-log-policy-section,
.process-section,
.faq-summary-section,
.download-page,
.article-page {
    background: #f4f7fb;
}

.split-grid,
.service-grid,
.privacy-grid,
.device-grid,
.protocol-grid,
.download-grid {
    display: grid;
    gap: 28px;
    align-items: center;
}

.image-panel,
.map-panel,
.speed-panel,
.security-panel,
.device-panel,
.protocol-panel {
    position: relative;
    padding: 20px;
    border-radius: 32px;
    background: linear-gradient(180deg, #ffffff, #f3f7ff);
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.map-panel {
    background: radial-gradient(circle at 25% 20%, rgba(41,128,254,.12), transparent 30%), radial-gradient(circle at 74% 65%, rgba(123,78,241,.14), transparent 34%), #ffffff;
}

.map-panel::before {
    content: "";
    position: absolute;
    inset: 24px;
    border-radius: 24px;
    background-image: linear-gradient(90deg, rgba(41,128,254,.08) 1px, transparent 1px), linear-gradient(rgba(41,128,254,.08) 1px, transparent 1px);
    background-size: 46px 46px;
}

.map-panel img,
.image-panel img,
.speed-panel img,
.security-panel img,
.device-panel img,
.protocol-panel img {
    position: relative;
    z-index: 2;
    margin: 0 auto;
    max-height: 330px;
    object-fit: contain;
}

.feature-list,
.check-list,
.step-list {
    padding: 0;
    margin: 18px 0 0;
    list-style: none;
    display: grid;
    gap: 10px;
}

.feature-list li,
.check-list li,
.step-list li {
    padding-left: 22px;
    position: relative;
    color: #475569;
}

.feature-list li::before,
.check-list li::before,
.step-list li::before {
    content: "";
    position: absolute;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    left: 0;
    top: 12px;
    background: var(--primary);
}

.info-grid,
.no-log-grid,
.risk-grid,
.faq-grid,
.related-grid {
    display: grid;
    gap: 16px;
}

.info-card,
.risk-card,
.faq-item,
.side-panel,
.notice-panel,
.download-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 22px;
    padding: 22px;
    box-shadow: 0 12px 34px rgba(15, 23, 42, 0.05);
}

.info-card.blue-line,
.risk-card {
    border-left: 4px solid var(--primary);
}

.security-panel .mini-card,
.protocol-panel .mini-card,
.speed-line-card {
    padding: 16px;
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid var(--line);
    margin-top: 14px;
}

.speed-lines {
    display: grid;
    gap: 12px;
    margin-top: 18px;
}

.speed-line-card {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.speed-line-card span {
    color: var(--muted);
}

.process-steps {
    display: grid;
    gap: 16px;
    counter-reset: step;
}

.process-step {
    position: relative;
    padding: 24px;
    border-radius: 24px;
    border: 1px solid var(--line);
    background: #fff;
    box-shadow: 0 10px 26px rgba(15, 23, 42, 0.05);
}

.process-step .num {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    margin-bottom: 12px;
    border-radius: 12px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
}

.cta-section {
    padding: 68px 0;
    background: var(--gradient);
    color: #fff;
    text-align: center;
}

.cta-box {
    width: min(860px, calc(100% - 32px));
    margin: 0 auto;
}

.cta-box h2 {
    margin: 0 0 12px;
    font-size: clamp(28px, 5vw, 44px);
    line-height: 1.2;
}

.cta-box p {
    margin: 0 auto 24px;
    max-width: 680px;
    color: rgba(255,255,255,.86);
}

.page-hero {
    background: linear-gradient(180deg, #eef5ff 0%, #ffffff 100%);
    padding: 58px 0 34px;
}

.page-hero h1 {
    margin: 0 0 14px;
    font-size: clamp(34px, 6vw, 54px);
    line-height: 1.12;
    letter-spacing: -0.04em;
}

.page-hero p {
    margin: 0;
    color: var(--muted);
    max-width: 820px;
    font-size: 17px;
}

.article-layout {
    display: grid;
    gap: 24px;
    align-items: start;
}

.article-main {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 24px;
    box-shadow: var(--shadow);
}

.article-main h2 {
    margin-top: 0;
    font-size: 26px;
}

.article-main p {
    color: #475569;
}

.side-panel {
    position: relative;
}

.side-panel h3,
.download-card h3,
.notice-panel h3 {
    margin-top: 0;
}

.side-panel a {
    display: block;
    color: var(--primary);
    font-weight: 700;
    padding: 8px 0;
    border-bottom: 1px solid var(--line);
}

.side-panel a:last-child {
    border-bottom: 0;
}

.download-card {
    text-align: center;
    margin-top: 18px;
}

.download-page .download-card {
    margin-top: 0;
}

.faq-list {
    display: grid;
    gap: 14px;
}

.faq-item strong {
    color: #0f172a;
}

.site-footer {
    background: #0f172a;
    color: #cbd5e1;
    padding-top: 52px;
}

.footer-grid {
    display: grid;
    gap: 24px;
}

.footer-brand {
    color: #fff;
    font-weight: 800;
    font-size: 22px;
    margin-bottom: 10px;
}

.site-footer h3 {
    color: #fff;
    margin: 0 0 12px;
}

.site-footer a {
    display: block;
    color: #cbd5e1;
    padding: 4px 0;
}

.site-footer a:hover {
    color: #fff;
}

.footer-bottom {
    margin-top: 36px;
    padding: 18px 0;
    text-align: center;
    border-top: 1px solid rgba(255,255,255,.1);
    color: #94a3b8;
}

@media (min-width: 640px) {
    .node-overview-grid,
    .info-grid,
    .no-log-grid,
    .risk-grid,
    .faq-grid,
    .related-grid,
    .process-steps {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 900px) {
    .mobile-nav {
        display: none;
    }

    .desktop-nav {
        position: static;
        display: flex;
        flex-direction: row;
        align-items: center;
        gap: 2px;
        padding: 0;
        background: transparent;
        border: 0;
        box-shadow: none;
    }

    .desktop-nav a {
        padding: 9px 10px;
        font-size: 14px;
    }

    .hero-grid,
    .split-grid,
    .service-grid,
    .privacy-grid,
    .device-grid,
    .protocol-grid,
    .download-grid {
        grid-template-columns: 1.02fr .98fr;
    }

    .node-overview-grid {
        grid-template-columns: repeat(4, 1fr);
    }

    .risk-grid,
    .faq-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .no-log-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .process-steps {
        grid-template-columns: repeat(3, 1fr);
    }

    .article-layout {
        grid-template-columns: minmax(0, 1fr) 320px;
    }

    .article-main {
        padding: 34px;
    }

    .footer-grid {
        grid-template-columns: 1.4fr 1fr 1fr 1.1fr;
    }
}

@media (min-width: 1120px) {
    .desktop-nav a {
        padding: 9px 12px;
    }

    .section {
        padding: 82px 0;
    }
}