* {
    box-sizing: border-box;
}

:root {
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #1f2937;
    --muted: #667085;
    --light: #f5f7fb;
    --line: #e5e9f2;
    --panel: #ffffff;
    --soft-blue: #eef5ff;
    --shadow: 0 18px 45px rgba(31, 41, 55, 0.08);
    --radius: 24px;
}

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;
}

img {
    max-width: 100%;
    display: block;
}

a {
    color: inherit;
    text-decoration: none;
}

.container {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(18px);
    border-bottom: 1px solid rgba(229, 233, 242, 0.9);
}

.header-inner {
    width: min(1160px, calc(100% - 28px));
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #111827;
    white-space: nowrap;
}

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

.site-nav {
    display: flex;
    align-items: center;
    gap: 4px;
}

.site-nav a {
    padding: 10px 12px;
    border-radius: 999px;
    color: #475467;
    font-size: 14px;
    transition: .2s ease;
}

.site-nav a:hover,
.site-nav a.active {
    color: var(--blue);
    background: #edf5ff;
}

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

.nav-toggle-label {
    display: none;
    width: 42px;
    height: 42px;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 5px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: #fff;
}

.nav-toggle-label span {
    width: 18px;
    height: 2px;
    background: #344054;
    border-radius: 999px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 26px;
    border-radius: 999px;
    background: var(--blue);
    color: #fff;
    font-weight: 700;
    box-shadow: 0 12px 24px rgba(41, 128, 254, 0.25);
    transition: .2s ease;
}

.download-btn:hover {
    background: var(--blue-dark);
    transform: translateY(-1px);
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    background: var(--gradient);
    color: #fff;
}

.vpn-network-hero::before,
.vpn-network-hero::after {
    content: "";
    position: absolute;
    border-radius: 999px;
    filter: blur(4px);
    opacity: .45;
}

.vpn-network-hero::before {
    width: 340px;
    height: 340px;
    background: rgba(255, 255, 255, .18);
    right: -90px;
    top: 30px;
}

.vpn-network-hero::after {
    width: 260px;
    height: 260px;
    background: rgba(255, 255, 255, .12);
    left: -120px;
    bottom: -80px;
}

.hero-grid {
    position: relative;
    z-index: 1;
    padding: 68px 0 82px;
    display: grid;
    gap: 34px;
    align-items: center;
}

.eyebrow,
.page-badge,
.card-label {
    display: inline-flex;
    align-items: center;
    width: fit-content;
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 700;
    background: rgba(41, 128, 254, 0.12);
    color: var(--blue);
}

.vpn-network-hero .eyebrow {
    color: #fff;
    background: rgba(255, 255, 255, .16);
    border: 1px solid rgba(255, 255, 255, .22);
}

.hero-content h1,
.sub-hero h1 {
    margin: 16px 0;
    font-size: clamp(34px, 7vw, 64px);
    line-height: 1.08;
    letter-spacing: -1.2px;
}

.hero-content p {
    margin: 0 0 24px;
    color: rgba(255, 255, 255, .88);
    font-size: 17px;
    max-width: 620px;
}

.hero-tags,
.inline-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 22px;
}

.hero-tags span,
.inline-tags span {
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(255, 255, 255, .14);
    border: 1px solid rgba(255, 255, 255, .18);
    font-size: 13px;
}

.hero-visual {
    position: relative;
    min-height: 360px;
    display: grid;
    place-items: center;
}

.hero-visual::before {
    content: "";
    position: absolute;
    inset: 10px;
    background: repeating-linear-gradient(135deg, rgba(255,255,255,.14) 0 1px, transparent 1px 28px);
    border-radius: 36px;
    opacity: .55;
}

.hero-visual img {
    position: relative;
    z-index: 1;
    width: min(440px, 92%);
    border-radius: 32px;
    box-shadow: 0 28px 60px rgba(15, 23, 42, .24);
}

.status-card {
    position: absolute;
    z-index: 2;
    padding: 10px 14px;
    border-radius: 16px;
    background: rgba(255,255,255,.92);
    color: #1f2937;
    border: 1px solid rgba(255,255,255,.5);
    box-shadow: var(--shadow);
    font-weight: 700;
    font-size: 13px;
}

.status-card.one { left: 8px; top: 40px; }
.status-card.two { right: 2px; top: 96px; }
.status-card.three { left: 18px; bottom: 84px; }
.status-card.four { right: 18px; bottom: 34px; }

.section,
.content-section {
    padding: 68px 0;
}

.section-soft {
    background: var(--light);
}

.section-head {
    max-width: 780px;
    margin-bottom: 28px;
}

.section-head.center {
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.section-head h2,
.article-card h2,
.panel h2 {
    margin: 10px 0 12px;
    font-size: clamp(26px, 4.8vw, 42px);
    line-height: 1.2;
    letter-spacing: -0.6px;
}

.section-head p,
.card p,
.article-card p,
.panel p,
.faq-item p,
.footer-grid p {
    color: var(--muted);
    margin: 0;
}

.node-overview {
    margin-top: -42px;
    position: relative;
    z-index: 2;
}

.node-grid,
.feature-grid,
.risk-grid,
.faq-grid,
.policy-grid,
.device-grid,
.protocol-grid {
    display: grid;
    gap: 16px;
}

.node-card,
.card,
.risk-card,
.faq-item,
.article-card,
.side-card,
.step-card,
.protocol-card,
.device-card {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 12px 30px rgba(31, 41, 55, .05);
}

.node-card {
    min-height: 190px;
}

.node-card h3,
.card h3,
.risk-card h3,
.faq-item h3,
.step-card h3,
.side-card h3,
.protocol-card h3,
.device-card h3 {
    margin: 12px 0 8px;
    font-size: 20px;
}

.inline-link,
.text-link {
    display: inline-flex;
    color: var(--blue);
    font-weight: 700;
    margin-top: 14px;
}

.split-section,
.article-layout {
    display: grid;
    gap: 28px;
    align-items: center;
}

.image-panel {
    position: relative;
    overflow: hidden;
    border-radius: 32px;
    background: #f0f5ff;
    padding: 20px;
    border: 1px solid var(--line);
}

.image-panel img {
    border-radius: 24px;
    width: 100%;
}

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

.point-list li,
.check-list li,
.step-list li {
    position: relative;
    padding-left: 26px;
    color: #344054;
}

.point-list li::before,
.check-list li::before,
.step-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 10px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--blue);
    box-shadow: 0 0 0 5px #e9f2ff;
}

.global-nodes-section {
    position: relative;
    overflow: hidden;
    background: linear-gradient(180deg, #f7faff 0%, #ffffff 100%);
}

.global-nodes-section::before {
    content: "";
    position: absolute;
    inset: 48px 0 auto;
    height: 260px;
    background:
        radial-gradient(circle at 18% 36%, rgba(41,128,254,.26) 0 5px, transparent 6px),
        radial-gradient(circle at 48% 30%, rgba(123,78,241,.25) 0 5px, transparent 6px),
        radial-gradient(circle at 76% 52%, rgba(184,77,218,.22) 0 5px, transparent 6px),
        linear-gradient(110deg, transparent 12%, rgba(41,128,254,.12) 12.5%, transparent 13%, transparent 47%, rgba(123,78,241,.11) 47.5%, transparent 48%);
    opacity: .9;
}

.high-speed-section {
    background: #f6f8fc;
}

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

.speed-line {
    padding: 14px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid var(--line);
}

.privacy-protection-section .privacy-panel,
.encryption-protocol-section .tech-panel {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 32px;
    padding: 24px;
    box-shadow: var(--shadow);
}

.no-log-policy-section {
    background: linear-gradient(180deg, #ffffff 0%, #f5f7fb 100%);
}

.process-steps {
    display: grid;
    gap: 14px;
    counter-reset: step;
}

.step-card {
    position: relative;
    padding-left: 72px;
}

.step-card::before {
    counter-increment: step;
    content: counter(step, decimal-leading-zero);
    position: absolute;
    left: 22px;
    top: 24px;
    width: 34px;
    height: 34px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: var(--blue);
    color: #fff;
    font-weight: 800;
}

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

.cta-section {
    padding: 70px 0;
    background: var(--gradient);
    color: #fff;
    text-align: center;
}

.cta-section p {
    color: rgba(255,255,255,.84);
    max-width: 720px;
    margin: 0 auto 24px;
}

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

.sub-hero {
    background: linear-gradient(180deg, #f5f8ff 0%, #ffffff 100%);
    padding: 58px 0 34px;
}

.sub-hero p {
    max-width: 780px;
    color: var(--muted);
    font-size: 17px;
}

.article-card {
    box-shadow: none;
}

.article-card h1,
.download-hero h1 {
    font-size: clamp(32px, 6vw, 52px);
    line-height: 1.15;
    margin: 16px 0;
}

.side-card {
    align-self: start;
    background: #f8fbff;
}

.notice-box {
    margin-top: 20px;
    padding: 18px;
    border-radius: 20px;
    background: #f3f7ff;
    border: 1px solid #dce9ff;
    color: #344054;
}

.single-action {
    margin-top: 26px;
}

.download-hero {
    text-align: center;
    padding: 68px 0 36px;
    background: linear-gradient(180deg, #eef5ff 0%, #ffffff 100%);
}

.download-hero p {
    margin: 0 auto 24px;
    max-width: 720px;
    color: var(--muted);
}

.download-steps {
    display: grid;
    gap: 16px;
}

.faq-list {
    display: grid;
    gap: 16px;
}

.faq-list .faq-item h2 {
    margin: 0 0 8px;
    font-size: 20px;
}

.site-footer {
    background: #111827;
    color: #d0d5dd;
    padding-top: 52px;
}

.footer-grid {
    display: grid;
    gap: 28px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #fff;
    margin-bottom: 12px;
}

.footer-brand img {
    width: 36px;
    height: 36px;
    border-radius: 12px;
    object-fit: cover;
}

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

.site-footer a {
    display: block;
    color: #d0d5dd;
    margin: 8px 0;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.1);
    margin-top: 36px;
    padding: 18px 16px;
    text-align: center;
    color: #98a2b3;
    font-size: 14px;
}

@media (max-width: 860px) {
    .nav-toggle-label {
        display: inline-flex;
    }

    .site-nav {
        position: absolute;
        top: 72px;
        left: 14px;
        right: 14px;
        display: none;
        flex-direction: column;
        align-items: stretch;
        padding: 14px;
        background: #fff;
        border: 1px solid var(--line);
        border-radius: 20px;
        box-shadow: var(--shadow);
    }

    .site-nav a {
        border-radius: 14px;
        padding: 12px 14px;
    }

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

    .status-card {
        position: relative;
        left: auto !important;
        right: auto !important;
        top: auto !important;
        bottom: auto !important;
        display: inline-flex;
        margin: 6px;
    }

    .hero-visual {
        min-height: auto;
    }

    .step-card {
        padding-left: 64px;
    }
}

@media (min-width: 640px) {
    .node-grid,
    .feature-grid,
    .risk-grid,
    .faq-grid,
    .policy-grid,
    .device-grid,
    .protocol-grid,
    .download-steps {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .process-steps {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (min-width: 900px) {
    .hero-grid,
    .split-section,
    .article-layout {
        grid-template-columns: 1.05fr .95fr;
    }

    .hero-grid {
        padding: 88px 0 104px;
    }

    .node-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }

    .feature-grid,
    .risk-grid,
    .policy-grid,
    .device-grid,
    .protocol-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .faq-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .footer-grid {
        grid-template-columns: 1.5fr .75fr .75fr;
    }

    .reverse .image-panel {
        order: -1;
    }
}

@media (min-width: 1120px) {
    .process-steps {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@media (max-width: 520px) {
    .container {
        width: min(100% - 24px, 1120px);
    }

    .section,
    .content-section {
        padding: 48px 0;
    }

    .hero-grid {
        padding: 52px 0 68px;
    }

    .node-card,
    .card,
    .risk-card,
    .faq-item,
    .article-card,
    .side-card,
    .step-card,
    .protocol-card,
    .device-card {
        padding: 18px;
        border-radius: 20px;
    }

    .download-btn {
        width: 100%;
        min-height: 52px;
    }
}