* {
    box-sizing: border-box;
}

:root {
    --brand-blue: #2980FE;
    --brand-blue-hover: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1f2937;
    --muted: #667085;
    --light: #f5f7fb;
    --line: #e6eaf2;
    --panel: #ffffff;
    --soft-blue: #eef5ff;
    --shadow: 0 18px 45px rgba(31, 41, 55, .08);
}

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: #fff;
    line-height: 1.7;
    overflow-x: hidden;
}

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

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

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, .94);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--line);
}

.header-inner {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.logo,
.footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: .2px;
    color: #111827;
}

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

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

.main-nav a {
    padding: 10px 13px;
    border-radius: 999px;
    color: #4b5563;
    font-size: 15px;
    transition: background .2s ease, color .2s ease;
}

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

.nav-toggle,
.nav-toggle-label {
    display: none;
}

.content-container,
.container {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
}

.section {
    padding: 72px 0;
}

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

.section-title {
    max-width: 760px;
    margin: 0 auto 34px;
    text-align: center;
}

.section-title .eyebrow,
.eyebrow,
.category-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 12px;
    border-radius: 999px;
    background: #edf5ff;
    color: var(--brand-blue);
    font-size: 14px;
    font-weight: 700;
    line-height: 1;
}

.section-title h2,
.page-hero h1,
.article-title h1 {
    margin: 16px 0 12px;
    font-size: clamp(30px, 5vw, 52px);
    line-height: 1.12;
    letter-spacing: -.8px;
}

.section-title p,
.page-hero p,
.article-title p {
    margin: 0;
    color: var(--muted);
    font-size: 17px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: var(--brand-blue);
    color: #fff;
    font-weight: 800;
    font-size: 16px;
    box-shadow: 0 16px 30px rgba(41, 128, 254, .22);
    transition: background .2s ease, transform .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    background: var(--brand-blue-hover);
    transform: translateY(-2px);
    box-shadow: 0 18px 38px rgba(23, 104, 232, .28);
}

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

.vpn-network-hero::before,
.cta-section::before,
.global-map-panel::before {
    content: "";
    position: absolute;
    inset: 0;
    opacity: .32;
    background-image:
        radial-gradient(circle at 16% 22%, rgba(255,255,255,.9) 0 2px, transparent 3px),
        radial-gradient(circle at 78% 26%, rgba(255,255,255,.85) 0 2px, transparent 3px),
        radial-gradient(circle at 48% 72%, rgba(255,255,255,.75) 0 2px, transparent 3px),
        linear-gradient(135deg, transparent 0 18%, rgba(255,255,255,.25) 18.2%, transparent 18.6% 48%, rgba(255,255,255,.2) 48.2%, transparent 48.7%);
    background-size: 260px 220px, 320px 260px, 240px 220px, 100% 100%;
}

.hero-inner {
    position: relative;
    z-index: 1;
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr;
    gap: 36px;
    padding: 72px 0 66px;
}

.hero-copy h1 {
    margin: 0 0 18px;
    font-size: clamp(36px, 8vw, 66px);
    line-height: 1.06;
    letter-spacing: -1px;
}

.hero-copy p {
    margin: 0 0 26px;
    max-width: 660px;
    color: rgba(255,255,255,.9);
    font-size: 17px;
}

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

.hero-tags span,
.status-tags span,
.inline-tags span {
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,.14);
    border: 1px solid rgba(255,255,255,.22);
    color: rgba(255,255,255,.94);
    font-size: 14px;
}

.hero-visual {
    position: relative;
    min-height: 320px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-device-card {
    width: min(420px, 88vw);
    padding: 18px;
    border-radius: 32px;
    background: rgba(255,255,255,.16);
    border: 1px solid rgba(255,255,255,.25);
    box-shadow: 0 24px 70px rgba(23, 33, 84, .28);
    backdrop-filter: blur(14px);
}

.hero-device-card img {
    border-radius: 24px;
    margin: 0 auto;
}

.float-card {
    position: absolute;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 13px;
    border-radius: 16px;
    background: rgba(255,255,255,.92);
    color: #243b66;
    box-shadow: 0 12px 28px rgba(23, 33, 84, .18);
    font-size: 14px;
    font-weight: 700;
}

.float-card.one { top: 16px; left: 4px; }
.float-card.two { top: 78px; right: 0; }
.float-card.three { bottom: 64px; left: 0; }
.float-card.four { bottom: 16px; right: 12px; }

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

.node-grid,
.feature-grid,
.policy-grid,
.risk-grid,
.faq-grid,
.card-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
}

.node-card,
.feature-card,
.policy-card,
.risk-card,
.faq-item,
.article-card,
.info-card,
.step-card {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 24px;
    padding: 24px;
    box-shadow: var(--shadow);
}

.node-card .tag,
.feature-card .tag,
.info-card .tag {
    display: inline-flex;
    padding: 6px 10px;
    margin-bottom: 12px;
    border-radius: 999px;
    color: var(--brand-blue);
    background: var(--soft-blue);
    font-size: 13px;
    font-weight: 800;
}

.node-card h3,
.feature-card h3,
.policy-card h3,
.risk-card h3,
.faq-item h3,
.article-card h2,
.info-card h3,
.step-card h3 {
    margin: 0 0 9px;
    font-size: 20px;
    line-height: 1.25;
}

.node-card p,
.feature-card p,
.policy-card p,
.risk-card p,
.faq-item p,
.article-card p,
.info-card p,
.step-card p {
    margin: 0;
    color: var(--muted);
}

.text-link {
    display: inline-flex;
    margin-top: 14px;
    color: var(--brand-blue);
    font-weight: 800;
}

.split-section,
.vpn-connection-section,
.high-speed-section,
.privacy-protection-section,
.multi-device-section,
.encryption-protocol-section {
    display: grid;
    grid-template-columns: 1fr;
    gap: 28px;
    align-items: center;
}

.media-panel,
.safety-panel,
.tech-panel,
.global-map-panel {
    position: relative;
    overflow: hidden;
    border-radius: 32px;
    padding: 22px;
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.media-panel img,
.safety-panel img,
.tech-panel img,
.global-map-panel img {
    border-radius: 24px;
    margin: 0 auto;
}

.copy-block h2 {
    margin: 12px 0 14px;
    font-size: clamp(28px, 5vw, 44px);
    line-height: 1.15;
}

.copy-block p {
    color: var(--muted);
    margin: 0 0 16px;
}

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

.point-list li,
.check-list li,
.basic-list li {
    position: relative;
    padding-left: 24px;
    color: #4b5563;
}

.point-list li::before,
.check-list li::before,
.basic-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: .72em;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--brand-blue);
}

.global-nodes-section {
    position: relative;
}

.global-map-panel {
    background: linear-gradient(135deg, #f8fbff 0%, #edf4ff 100%);
}

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

.node-line {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 13px 14px;
    border-radius: 16px;
    background: rgba(255,255,255,.86);
    border: 1px solid var(--line);
}

.node-line span:first-child {
    color: #344054;
    font-weight: 700;
}

.node-line span:last-child {
    color: var(--brand-blue);
    font-weight: 800;
}

.speed-cards {
    display: grid;
    gap: 14px;
    margin-top: 20px;
}

.speed-card {
    padding: 16px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid var(--line);
}

.speed-card strong {
    display: block;
    margin-bottom: 6px;
}

.privacy-tags {
    display: grid;
    gap: 12px;
    margin-top: 16px;
}

.privacy-tag {
    padding: 14px;
    border-left: 4px solid var(--brand-blue);
    border-radius: 16px;
    background: #f7fbff;
}

.privacy-tag strong {
    display: block;
    margin-bottom: 5px;
}

.protocol-grid {
    display: grid;
    gap: 14px;
    margin-top: 18px;
}

.protocol-item {
    padding: 16px;
    border-radius: 18px;
    background: #f8fafc;
    border: 1px solid var(--line);
}

.process-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    counter-reset: step;
}

.step-card {
    position: relative;
    padding-top: 56px;
}

.step-card::before {
    counter-increment: step;
    content: counter(step, decimal-leading-zero);
    position: absolute;
    top: 20px;
    left: 22px;
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    background: var(--brand-blue);
    color: #fff;
    font-weight: 900;
}

.risk-card {
    border-top: 4px solid var(--brand-blue);
    box-shadow: none;
}

.risk-card .suggest {
    margin-top: 12px;
    padding: 12px;
    border-radius: 14px;
    background: #f7fbff;
    color: #344054;
}

.faq-item {
    box-shadow: none;
}

.cta-section {
    position: relative;
    overflow: hidden;
    margin: 40px 0 0;
    padding: 64px 0;
    color: #fff;
    background: var(--gradient);
}

.cta-inner {
    position: relative;
    z-index: 1;
    width: min(840px, calc(100% - 32px));
    margin: 0 auto;
    text-align: center;
}

.cta-inner h2 {
    margin: 0 0 12px;
    font-size: clamp(28px, 6vw, 46px);
    line-height: 1.14;
}

.cta-inner p {
    margin: 0 auto 24px;
    color: rgba(255,255,255,.88);
    max-width: 650px;
}

.page-hero,
.article-title {
    padding: 66px 0 38px;
    background: linear-gradient(180deg, #f6f9ff 0%, #fff 100%);
}

.page-hero .container,
.article-title .container {
    max-width: 980px;
}

.article-layout {
    width: min(1080px, calc(100% - 32px));
    margin: 0 auto;
    padding: 32px 0 72px;
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

.article-main {
    display: grid;
    gap: 22px;
}

.article-card ul,
.article-card ol,
.info-card ul,
.info-card ol {
    margin: 14px 0 0;
    padding-left: 20px;
    color: #4b5563;
}

.article-card li,
.info-card li {
    margin: 8px 0;
}

.side-panel {
    display: grid;
    gap: 16px;
    align-content: start;
}

.side-panel .info-card {
    position: sticky;
    top: 92px;
    box-shadow: none;
}

.download-panel {
    display: grid;
    place-items: center;
    gap: 14px;
    text-align: center;
}

.download-steps {
    display: grid;
    gap: 14px;
    margin-top: 20px;
}

.download-step {
    display: flex;
    gap: 14px;
    padding: 16px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid var(--line);
}

.download-step span {
    flex: 0 0 34px;
    width: 34px;
    height: 34px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: var(--brand-blue);
    color: #fff;
    font-weight: 900;
}

.site-footer {
    background: #111827;
    color: #e5e7eb;
}

.footer-inner {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    padding: 48px 0;
    display: grid;
    grid-template-columns: 1fr;
    gap: 34px;
}

.footer-brand p {
    max-width: 420px;
    color: #aeb7c5;
}

.footer-logo {
    color: #fff;
}

.footer-links {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
}

.footer-links h3 {
    margin: 0 0 12px;
    font-size: 16px;
    color: #fff;
}

.footer-links a {
    display: block;
    margin: 8px 0;
    color: #aeb7c5;
    font-size: 14px;
}

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

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.1);
    text-align: center;
    padding: 18px 16px;
    color: #aeb7c5;
    font-size: 14px;
}

@media (max-width: 860px) {
    .nav-toggle-label {
        display: inline-flex;
        width: 42px;
        height: 42px;
        flex-direction: column;
        justify-content: center;
        gap: 5px;
        padding: 0 10px;
        border-radius: 14px;
        border: 1px solid var(--line);
        background: #fff;
        cursor: pointer;
    }

    .nav-toggle-label span {
        height: 2px;
        width: 100%;
        background: #1f2937;
        border-radius: 10px;
    }

    .main-nav {
        position: absolute;
        left: 16px;
        right: 16px;
        top: 68px;
        display: none;
        flex-direction: column;
        align-items: stretch;
        padding: 14px;
        border: 1px solid var(--line);
        border-radius: 22px;
        background: #fff;
        box-shadow: var(--shadow);
    }

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

    .main-nav a {
        border-radius: 14px;
    }
}

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

    .footer-links {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@media (min-width: 900px) {
    .hero-inner {
        grid-template-columns: minmax(0, 1.06fr) minmax(380px, .94fr);
        align-items: center;
        min-height: 640px;
    }

    .split-section,
    .vpn-connection-section,
    .high-speed-section,
    .privacy-protection-section,
    .multi-device-section,
    .encryption-protocol-section {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 56px;
    }

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

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

    .process-steps {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .article-layout {
        grid-template-columns: minmax(0, 1fr) 310px;
    }

    .footer-inner {
        grid-template-columns: .85fr 1.15fr;
    }
}

@media (max-width: 520px) {
    .section {
        padding: 52px 0;
    }

    .hero-inner {
        padding: 54px 0 58px;
    }

    .hero-tags span,
    .status-tags span,
    .inline-tags span {
        font-size: 13px;
    }

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

    .float-card {
        position: static;
        margin: 8px;
    }

    .hero-visual {
        flex-direction: column;
    }

    .article-card,
    .info-card,
    .node-card,
    .feature-card,
    .policy-card,
    .risk-card,
    .faq-item,
    .step-card {
        padding: 20px;
        border-radius: 20px;
    }
}