* {
    box-sizing: border-box;
}

:root {
    --primary: #2980FE;
    --primary-dark: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1f2937;
    --muted: #64748b;
    --light: #f7f9fc;
    --soft-blue: #eef5ff;
    --border: #e5eaf2;
    --card: #ffffff;
    --deep: #111827;
    --radius: 24px;
    --shadow: 0 16px 40px rgba(15, 23, 42, 0.08);
}

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: 1.7;
}

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

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

p {
    margin: 0 0 14px;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255, 255, 255, 0.94);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(229, 234, 242, 0.9);
}

.header-inner {
    width: min(1160px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 21px;
    color: #172554;
    flex-shrink: 0;
}

.logo img {
    width: 42px;
    height: 42px;
    border-radius: 14px;
    object-fit: cover;
}

.nav-toggle {
    display: none;
}

.nav-toggle-label {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border);
    color: var(--text);
    border-radius: 999px;
    padding: 8px 14px;
    font-size: 14px;
    background: #fff;
}

.site-nav {
    display: none;
    position: absolute;
    top: 70px;
    left: 16px;
    right: 16px;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 22px;
    box-shadow: var(--shadow);
    padding: 12px;
}

.site-nav a {
    display: block;
    padding: 11px 14px;
    color: #334155;
    font-weight: 600;
    border-radius: 14px;
}

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

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

.container {
    width: min(1160px, calc(100% - 32px));
    margin: 0 auto;
}

.narrow-container {
    width: min(900px, calc(100% - 32px));
    margin: 0 auto;
}

.section {
    padding: 58px 0;
}

.section-title {
    margin: 0 0 12px;
    font-size: clamp(28px, 5vw, 44px);
    line-height: 1.2;
    letter-spacing: -0.04em;
    color: var(--deep);
}

.section-lead {
    color: var(--muted);
    font-size: 16px;
    max-width: 780px;
}

.eyebrow,
.badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--primary);
    background: rgba(41, 128, 254, 0.1);
    border: 1px solid rgba(41, 128, 254, 0.18);
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 800;
    margin-bottom: 14px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: #2980FE;
    color: #fff;
    font-weight: 800;
    box-shadow: 0 12px 26px rgba(41, 128, 254, 0.25);
    transition: background .2s ease, transform .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    background: #1768E8;
    transform: translateY(-2px);
    box-shadow: 0 16px 30px rgba(23, 104, 232, 0.28);
}

.link-more {
    color: var(--primary);
    font-weight: 800;
    display: inline-flex;
    margin-top: 8px;
}

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

.vpn-network-hero::before,
.vpn-network-hero::after {
    content: "";
    position: absolute;
    inset: auto;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.18);
    filter: blur(8px);
}

.vpn-network-hero::before {
    width: 420px;
    height: 420px;
    right: -160px;
    top: -130px;
}

.vpn-network-hero::after {
    width: 320px;
    height: 320px;
    left: -140px;
    bottom: -110px;
}

.hero-grid {
    position: relative;
    z-index: 1;
    width: min(1160px, calc(100% - 32px));
    margin: 0 auto;
    padding: 74px 0 64px;
    display: grid;
    gap: 36px;
}

.hero-copy h1 {
    margin: 0 0 18px;
    font-size: clamp(38px, 9vw, 68px);
    line-height: 1.08;
    letter-spacing: -0.06em;
}

.hero-copy p {
    color: rgba(255, 255, 255, 0.88);
    font-size: 17px;
    max-width: 620px;
}

.hero-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 24px 0;
}

.hero-tags span {
    background: rgba(255, 255, 255, 0.14);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 999px;
    padding: 8px 12px;
    font-weight: 700;
    color: rgba(255, 255, 255, 0.92);
}

.hero-visual {
    position: relative;
    min-height: 360px;
    border-radius: 34px;
    padding: 24px;
    background:
        radial-gradient(circle at 20% 20%, rgba(255,255,255,.2), transparent 28%),
        linear-gradient(135deg, rgba(255,255,255,.22), rgba(255,255,255,.08));
    border: 1px solid rgba(255,255,255,.22);
    box-shadow: 0 28px 70px rgba(23, 37, 84, 0.25);
}

.hero-visual::before {
    content: "";
    position: absolute;
    inset: 28px;
    border-radius: 28px;
    background-image:
        linear-gradient(rgba(255,255,255,.18) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.18) 1px, transparent 1px);
    background-size: 42px 42px;
    opacity: .38;
}

.hero-visual img {
    position: relative;
    z-index: 2;
    width: min(390px, 82%);
    margin: 18px auto 0;
    filter: drop-shadow(0 22px 36px rgba(17, 24, 39, 0.22));
}

.status-pill {
    position: absolute;
    z-index: 3;
    background: rgba(255, 255, 255, 0.92);
    color: #172554;
    border-radius: 999px;
    padding: 9px 13px;
    font-weight: 800;
    box-shadow: var(--shadow);
    font-size: 13px;
}

.status-pill.one { top: 30px; left: 24px; }
.status-pill.two { top: 86px; right: 24px; }
.status-pill.three { bottom: 92px; left: 18px; }
.status-pill.four { bottom: 28px; right: 30px; }

.node-overview {
    margin-top: -36px;
    position: relative;
    z-index: 3;
}

.node-overview-grid {
    display: grid;
    gap: 14px;
}

.node-card,
.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 10px 28px rgba(15, 23, 42, 0.06);
}

.node-card .label {
    display: inline-block;
    color: var(--primary);
    background: rgba(41, 128, 254, .1);
    border-radius: 999px;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 800;
    margin-bottom: 10px;
}

.node-card h3,
.card h3 {
    margin: 0 0 8px;
    color: var(--deep);
    font-size: 20px;
}

.node-card p,
.card p {
    color: var(--muted);
}

.vpn-connection-section,
.global-nodes-section,
.high-speed-section,
.privacy-protection-section,
.multi-device-section,
.encryption-protocol-section,
.content-split,
.about-grid {
    display: grid;
    gap: 28px;
    align-items: center;
}

.visual-card {
    border-radius: 30px;
    padding: 24px;
    background: linear-gradient(135deg, #f8fbff, #eef5ff);
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
}

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

.feature-list {
    display: grid;
    gap: 12px;
    margin: 20px 0 8px;
}

.feature-list span,
.check-list li {
    display: flex;
    gap: 10px;
    align-items: flex-start;
    color: #334155;
}

.feature-list span::before,
.check-list li::before {
    content: "";
    width: 8px;
    height: 8px;
    margin-top: 10px;
    border-radius: 999px;
    flex: 0 0 auto;
    background: var(--primary);
}

.global-nodes-wrap {
    border-radius: 34px;
    padding: 26px;
    background:
        radial-gradient(circle at 20% 24%, rgba(41,128,254,.16), transparent 26%),
        radial-gradient(circle at 80% 18%, rgba(184,77,218,.16), transparent 24%),
        linear-gradient(135deg, #f8fbff 0%, #eef5ff 100%);
    border: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.global-nodes-wrap::before {
    content: "";
    position: absolute;
    inset: 18px;
    background-image:
        radial-gradient(circle, rgba(41,128,254,.3) 2px, transparent 3px),
        linear-gradient(115deg, transparent 0 44%, rgba(41,128,254,.15) 45% 46%, transparent 47% 100%);
    background-size: 72px 72px, 100% 100%;
    opacity: .58;
}

.global-nodes-wrap > * {
    position: relative;
    z-index: 1;
}

.speed-panel {
    background: var(--light);
    border-radius: 34px;
    padding: 28px;
    border: 1px solid var(--border);
}

.speed-lines {
    display: grid;
    gap: 12px;
    margin-top: 20px;
}

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

.speed-line b {
    color: var(--primary);
}

.privacy-panel {
    background: #fff;
    border-radius: 30px;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    padding: 24px;
}

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

.privacy-tags span {
    background: var(--soft-blue);
    color: #1d4ed8;
    border-radius: 999px;
    padding: 7px 11px;
    font-weight: 800;
    font-size: 13px;
}

.no-log-policy-section {
    background: var(--light);
}

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

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

.policy-card h3 {
    margin: 0 0 8px;
}

.device-card {
    border-radius: 26px;
    padding: 22px;
    background: #fff;
    border: 1px solid var(--border);
    box-shadow: 0 10px 26px rgba(15,23,42,.05);
}

.protocol-panel {
    border-radius: 30px;
    background: linear-gradient(135deg, #ffffff, #f7faff);
    border: 1px solid var(--border);
    padding: 26px;
}

.protocol-item {
    border-left: 4px solid var(--primary);
    padding: 12px 0 12px 14px;
    color: var(--muted);
}

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

.step-card {
    position: relative;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 22px 22px 22px 74px;
    box-shadow: 0 8px 24px rgba(15,23,42,.05);
}

.step-card::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 22px;
    top: 22px;
    width: 36px;
    height: 36px;
    display: grid;
    place-items: center;
    color: #fff;
    background: var(--primary);
    border-radius: 14px;
    font-weight: 900;
}

.step-card h3 {
    margin: 0 0 6px;
}

.risk-card {
    background: #fff;
    border: 1px solid var(--border);
    border-left: 4px solid var(--primary);
    border-radius: 22px;
    padding: 20px;
}

.risk-card h3 {
    margin: 0 0 8px;
    color: var(--deep);
}

.risk-card p {
    color: var(--muted);
}

.faq-item {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 22px;
    padding: 20px;
}

.faq-item h3 {
    margin: 0 0 8px;
    color: var(--deep);
}

.cta-section {
    background: var(--gradient);
    color: #fff;
    text-align: center;
    padding: 62px 0;
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: "";
    position: absolute;
    width: 360px;
    height: 360px;
    border-radius: 999px;
    background: rgba(255, 255, 255, .14);
    top: -160px;
    right: -120px;
}

.cta-inner {
    position: relative;
    z-index: 1;
    width: min(820px, calc(100% - 32px));
    margin: 0 auto;
}

.cta-inner h2 {
    margin: 0 0 12px;
    font-size: clamp(28px, 6vw, 46px);
    line-height: 1.16;
}

.cta-inner p {
    color: rgba(255,255,255,.88);
    margin-bottom: 24px;
}

.page-hero {
    background: linear-gradient(180deg, #f6f9ff 0%, #ffffff 100%);
    padding: 54px 0 30px;
    border-bottom: 1px solid var(--border);
}

.page-hero h1 {
    margin: 0 0 14px;
    font-size: clamp(34px, 7vw, 58px);
    line-height: 1.12;
    letter-spacing: -0.05em;
    color: var(--deep);
}

.page-hero p {
    color: var(--muted);
    font-size: 17px;
    max-width: 760px;
}

.article-layout {
    display: grid;
    gap: 24px;
    padding: 42px 0 64px;
}

.article-main {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 28px;
    padding: 24px;
    box-shadow: 0 10px 28px rgba(15,23,42,.05);
}

.article-main h2 {
    margin: 26px 0 10px;
    color: var(--deep);
}

.article-main h2:first-child {
    margin-top: 0;
}

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

.article-main ul,
.article-main ol {
    padding-left: 20px;
    margin: 12px 0 18px;
}

.side-panel {
    background: #f8fbff;
    border: 1px solid var(--border);
    border-radius: 28px;
    padding: 22px;
    align-self: start;
}

.side-panel h2,
.side-panel h3 {
    margin: 0 0 10px;
}

.tip-box {
    background: var(--soft-blue);
    border: 1px solid rgba(41,128,254,.16);
    border-radius: 22px;
    padding: 18px;
    margin: 18px 0;
}

.tip-box strong {
    color: #1d4ed8;
}

.download-center {
    display: grid;
    gap: 22px;
    align-items: center;
    padding: 54px 0 70px;
}

.download-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 32px;
    padding: 28px;
    box-shadow: var(--shadow);
    text-align: center;
}

.download-card h1 {
    margin: 0 0 14px;
    font-size: clamp(34px, 7vw, 56px);
    line-height: 1.12;
    color: var(--deep);
}

.install-steps {
    display: grid;
    gap: 14px;
    margin-top: 26px;
}

.install-step {
    display: flex;
    gap: 14px;
    align-items: flex-start;
    background: #f8fbff;
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 16px;
    text-align: left;
}

.install-step b {
    width: 32px;
    height: 32px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: var(--primary);
    color: #fff;
    flex-shrink: 0;
}

.faq-page {
    padding: 44px 0 64px;
}

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

.faq-list .faq-item {
    padding: 22px;
}

.site-footer {
    background: #0f172a;
    color: #dbeafe;
    padding: 50px 0 0;
}

.footer-inner {
    width: min(1160px, calc(100% - 32px));
    margin: 0 auto;
    display: grid;
    gap: 28px;
}

.footer-logo {
    color: #fff;
    font-size: 26px;
    font-weight: 900;
    margin-bottom: 10px;
}

.footer-brand p {
    color: #cbd5e1;
    max-width: 460px;
}

.footer-links {
    display: grid;
    gap: 20px;
}

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

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

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

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.1);
    margin-top: 38px;
    padding: 18px 16px;
    color: #cbd5e1;
    font-size: 14px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px 22px;
    justify-content: center;
    text-align: center;
}

@media (min-width: 640px) {
    .node-overview-grid,
    .policy-grid,
    .device-grid,
    .protocol-grid,
    .risk-grid,
    .faq-grid,
    .help-grid,
    .related-grid,
    .install-steps {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

    .site-nav {
        display: flex;
        position: static;
        box-shadow: none;
        border: 0;
        background: transparent;
        padding: 0;
        align-items: center;
        gap: 2px;
        flex-wrap: wrap;
        justify-content: flex-end;
    }

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

    .hero-grid {
        grid-template-columns: 1.02fr .98fr;
        align-items: center;
        padding: 92px 0 82px;
    }

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

    .vpn-connection-section,
    .global-nodes-section,
    .high-speed-section,
    .privacy-protection-section,
    .multi-device-section,
    .encryption-protocol-section,
    .content-split,
    .about-grid,
    .download-center {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

    .article-main {
        padding: 34px;
    }

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

    .policy-grid,
    .device-grid,
    .protocol-grid,
    .help-grid {
        grid-template-columns: repeat(3, 1fr);
    }

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

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

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

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

@media (max-width: 480px) {
    .header-inner {
        width: min(100% - 22px, 1160px);
    }

    .container,
    .narrow-container,
    .hero-grid {
        width: min(100% - 24px, 1160px);
    }

    .section {
        padding: 46px 0;
    }

    .hero-visual {
        min-height: 310px;
        padding: 18px;
    }

    .status-pill {
        position: static;
        display: inline-flex;
        margin: 6px 6px 0 0;
    }

    .hero-visual img {
        width: 86%;
        margin-top: 12px;
    }

    .download-btn {
        width: 100%;
        padding: 14px 20px;
    }

    .article-main,
    .download-card,
    .side-panel {
        padding: 20px;
    }
}