* {
    box-sizing: border-box;
}

:root {
    --primary: #2980FE;
    --primary-dark: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #243043;
    --muted: #657186;
    --light: #F6F8FC;
    --line: #E6EAF2;
    --card: #FFFFFF;
    --deep: #152034;
    --shadow: 0 18px 45px rgba(31, 53, 94, .12);
    --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: 1.72;
    overflow-x: hidden;
}

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

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

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

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

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255, 255, 255, .94);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(16px);
}

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

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    flex: 0 0 auto;
}

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

.brand-name {
    font-size: 20px;
    font-weight: 800;
    letter-spacing: .02em;
    color: var(--deep);
}

.nav-toggle {
    display: none;
}

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

.nav-toggle-label span {
    width: 18px;
    height: 2px;
    border-radius: 2px;
    background: var(--deep);
}

.site-nav {
    position: absolute;
    left: 14px;
    right: 14px;
    top: 72px;
    display: none;
    padding: 12px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: var(--shadow);
}

.nav-toggle:checked ~ .site-nav {
    display: grid;
    gap: 4px;
}

.site-nav a {
    padding: 11px 12px;
    border-radius: 12px;
    color: #44506A;
    font-size: 15px;
    font-weight: 600;
}

.site-nav a:hover,
.site-nav a.active {
    color: var(--primary);
    background: #EEF5FF;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    letter-spacing: .02em;
    box-shadow: 0 14px 30px rgba(41, 128, 254, .28);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
    border: 0;
}

.download-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 18px 38px rgba(23, 104, 232, .3);
}

.section {
    padding: 64px 0;
}

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

.section-title {
    margin: 0 0 12px;
    font-size: clamp(28px, 5vw, 44px);
    line-height: 1.18;
    color: var(--deep);
    letter-spacing: -.03em;
}

.section-lead {
    margin: 0;
    color: var(--muted);
    font-size: 17px;
}

.section-head {
    margin-bottom: 28px;
    display: grid;
    gap: 10px;
}

.eyebrow,
.category-badge,
.mini-tag {
    display: inline-flex;
    width: fit-content;
    align-items: center;
    gap: 6px;
    border-radius: 999px;
    padding: 7px 12px;
    background: #EDF5FF;
    color: var(--primary);
    font-size: 13px;
    font-weight: 800;
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #fff;
    background: var(--gradient);
    padding: 58px 0 66px;
}

.vpn-network-hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 18% 18%, rgba(255,255,255,.25), transparent 24%),
        radial-gradient(circle at 82% 30%, rgba(255,255,255,.18), transparent 22%),
        linear-gradient(135deg, rgba(255,255,255,.18) 1px, transparent 1px);
    background-size: auto, auto, 38px 38px;
    opacity: .55;
}

.hero-grid {
    position: relative;
    display: grid;
    gap: 34px;
    align-items: center;
}

.hero-copy h1 {
    margin: 14px 0 16px;
    font-size: clamp(38px, 9vw, 68px);
    line-height: 1.05;
    letter-spacing: -.05em;
}

.hero-copy p {
    margin: 0 0 24px;
    color: rgba(255,255,255,.9);
    font-size: 18px;
}

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

.hero-tags span,
.visual-tag {
    display: inline-flex;
    padding: 8px 12px;
    border: 1px solid rgba(255,255,255,.28);
    border-radius: 999px;
    background: rgba(255,255,255,.14);
    color: #fff;
    font-size: 13px;
    font-weight: 700;
    backdrop-filter: blur(10px);
}

.hero-visual {
    position: relative;
    min-height: 320px;
    display: grid;
    place-items: center;
}

.hero-device {
    width: min(420px, 88%);
    border-radius: 30px;
    filter: drop-shadow(0 30px 55px rgba(18, 25, 57, .25));
    position: relative;
    z-index: 2;
}

.node-orbit {
    position: absolute;
    width: 86%;
    aspect-ratio: 1 / 1;
    border: 1px solid rgba(255,255,255,.28);
    border-radius: 50%;
}

.node-orbit::before,
.node-orbit::after {
    content: "";
    position: absolute;
    width: 10px;
    height: 10px;
    background: #fff;
    border-radius: 50%;
    box-shadow: 0 0 22px rgba(255,255,255,.9);
}

.node-orbit::before { left: 12%; top: 18%; }
.node-orbit::after { right: 14%; bottom: 22%; }

.float-card {
    position: absolute;
    z-index: 3;
    padding: 10px 13px;
    border-radius: 16px;
    background: rgba(255,255,255,.92);
    color: var(--deep);
    box-shadow: 0 16px 36px rgba(10, 22, 50, .16);
    font-size: 13px;
    font-weight: 800;
}

.float-card.one { top: 8%; left: 2%; }
.float-card.two { top: 20%; right: 1%; }
.float-card.three { bottom: 18%; left: 5%; }
.float-card.four { bottom: 8%; right: 7%; }

.node-overview {
    margin-top: -38px;
    position: relative;
    z-index: 4;
}

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

.node-card,
.info-card,
.risk-card,
.faq-item,
.policy-card,
.step-card,
.tip-card,
.page-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: 0 12px 30px rgba(29, 45, 78, .06);
}

.node-card {
    padding: 22px;
}

.node-card .label {
    color: var(--primary);
    font-weight: 900;
    font-size: 13px;
}

.node-card h3,
.info-card h3,
.risk-card h3,
.policy-card h3,
.step-card h3,
.tip-card h3,
.page-card h3 {
    margin: 8px 0 8px;
    color: var(--deep);
    line-height: 1.3;
}

.node-card p,
.info-card p,
.risk-card p,
.policy-card p,
.step-card p,
.tip-card p,
.page-card p {
    margin: 0;
    color: var(--muted);
}

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

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

.media-panel {
    border-radius: 30px;
    background: linear-gradient(145deg, #F4F8FF, #FFFFFF);
    border: 1px solid var(--line);
    padding: 24px;
    box-shadow: var(--shadow);
}

.media-panel img {
    margin: 0 auto;
    border-radius: 24px;
}

.feature-list,
.clean-list {
    list-style: none;
    padding: 0;
    margin: 22px 0 0;
    display: grid;
    gap: 12px;
}

.feature-list li,
.clean-list li {
    position: relative;
    padding-left: 30px;
    color: #43506A;
}

.feature-list li::before,
.clean-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 10px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--primary);
    box-shadow: 0 0 0 6px #EAF3FF;
}

.global-nodes-section {
    background:
        radial-gradient(circle at 20% 20%, #EAF2FF 0, transparent 30%),
        radial-gradient(circle at 80% 10%, #F5EAFE 0, transparent 26%),
        #FFFFFF;
}

.map-panel {
    position: relative;
    overflow: hidden;
    border-radius: 32px;
    border: 1px solid var(--line);
    background: #fff;
    padding: 24px;
    box-shadow: var(--shadow);
}

.map-panel::before {
    content: "";
    position: absolute;
    inset: 18px;
    border-radius: 28px;
    background:
        linear-gradient(90deg, rgba(41,128,254,.12) 1px, transparent 1px),
        linear-gradient(0deg, rgba(41,128,254,.1) 1px, transparent 1px);
    background-size: 42px 42px;
}

.map-panel img,
.map-panel .node-points {
    position: relative;
    z-index: 2;
}

.node-points {
    display: grid;
    gap: 10px;
    margin-top: 16px;
}

.node-points span {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: #3C4861;
    font-weight: 700;
}

.node-points span::before {
    content: "";
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--primary);
    box-shadow: 0 0 0 7px rgba(41,128,254,.12);
}

.speed-grid {
    display: grid;
    gap: 18px;
}

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

.speed-line {
    height: 8px;
    border-radius: 99px;
    background: linear-gradient(90deg, #D8E8FF, #2980FE);
    margin-top: 14px;
}

.privacy-panel,
.protocol-panel {
    padding: 26px;
    border-radius: 30px;
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

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

.privacy-tags span,
.protocol-grid span {
    border-radius: 999px;
    padding: 8px 12px;
    background: #F1F6FF;
    color: var(--primary);
    font-weight: 800;
    font-size: 13px;
}

.policy-grid,
.risk-grid,
.faq-grid,
.card-grid {
    display: grid;
    gap: 16px;
}

.policy-card,
.risk-card,
.info-card,
.page-card,
.tip-card {
    padding: 22px;
}

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

.device-grid {
    display: grid;
    gap: 18px;
    margin-top: 22px;
}

.device-card {
    padding: 18px;
    border-radius: 22px;
    background: #fff;
    border: 1px solid var(--line);
}

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

.step-card {
    padding: 22px;
    position: relative;
}

.step-number {
    display: inline-grid;
    place-items: center;
    width: 38px;
    height: 38px;
    border-radius: 14px;
    background: var(--gradient);
    color: #fff;
    font-weight: 900;
}

.faq-item {
    padding: 20px;
}

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

.faq-item p {
    margin: 0;
    color: var(--muted);
}

.cta-section {
    padding: 58px 0;
    color: #fff;
    background: var(--gradient);
    position: relative;
    overflow: hidden;
}

.cta-section::after {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 15% 20%, rgba(255,255,255,.22), transparent 25%), radial-gradient(circle at 80% 70%, rgba(255,255,255,.18), transparent 28%);
}

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

.cta-card h2 {
    margin: 0 0 12px;
    font-size: clamp(28px, 6vw, 46px);
    line-height: 1.15;
}

.cta-card p {
    margin: 0 auto 24px;
    color: rgba(255,255,255,.88);
    max-width: 680px;
}

.page-hero {
    padding: 52px 0 34px;
    background: linear-gradient(180deg, #F5F8FF 0%, #FFFFFF 100%);
    border-bottom: 1px solid var(--line);
}

.page-hero h1 {
    margin: 14px 0 12px;
    font-size: clamp(34px, 7vw, 56px);
    line-height: 1.12;
    letter-spacing: -.04em;
    color: var(--deep);
}

.page-hero p {
    margin: 0;
    color: var(--muted);
    font-size: 18px;
}

.page-layout {
    display: grid;
    gap: 22px;
    align-items: start;
}

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

.article-panel section,
.download-panel {
    padding: 24px;
    border-radius: 26px;
    border: 1px solid var(--line);
    background: #fff;
    box-shadow: 0 12px 30px rgba(29, 45, 78, .05);
}

.article-panel h2,
.download-panel h2 {
    margin: 0 0 10px;
    color: var(--deep);
    line-height: 1.3;
}

.article-panel p,
.download-panel p {
    margin: 0 0 12px;
    color: var(--muted);
}

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

.notice-box {
    padding: 20px;
    border-radius: 24px;
    border: 1px solid #D9E8FF;
    background: #F3F8FF;
    color: #37506E;
}

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

.download-step {
    display: grid;
    grid-template-columns: 44px 1fr;
    gap: 14px;
    align-items: start;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 22px;
    background: #fff;
}

.download-step strong {
    display: grid;
    place-items: center;
    width: 40px;
    height: 40px;
    border-radius: 14px;
    background: #EDF5FF;
    color: var(--primary);
}

.site-footer {
    background: #101A2C;
    color: rgba(255,255,255,.76);
    padding-top: 46px;
}

.footer-grid {
    display: grid;
    gap: 26px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #fff;
    font-size: 20px;
}

.footer-brand img {
    width: 34px;
    height: 34px;
    border-radius: 10px;
}

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

.site-footer a {
    display: block;
    margin: 7px 0;
    color: rgba(255,255,255,.76);
}

.footer-bottom {
    margin-top: 36px;
    padding: 18px;
    text-align: center;
    border-top: 1px solid rgba(255,255,255,.12);
    color: rgba(255,255,255,.62);
    font-size: 14px;
}

@media (min-width: 720px) {
    .node-overview-grid,
    .policy-grid,
    .risk-grid,
    .card-grid,
    .faq-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

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

    .footer-grid {
        grid-template-columns: 1.4fr repeat(3, 1fr);
    }
}

@media (min-width: 980px) {
    .nav-toggle-label {
        display: none;
    }

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

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

    .vpn-network-hero {
        padding: 84px 0 92px;
    }

    .hero-grid,
    .split-section,
    .page-layout {
        grid-template-columns: minmax(0, 1fr) minmax(360px, .86fr);
    }

    .hero-copy p {
        font-size: 20px;
    }

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

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

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

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

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

    .section {
        padding: 86px 0;
    }
}

@media (max-width: 430px) {
    .download-btn {
        width: 100%;
    }

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

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

    .node-orbit {
        display: none;
    }
}