* {
    box-sizing: border-box;
}
:root {
    --primary: #2980FE;
    --primary-dark: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1f2937;
    --muted: #667085;
    --light: #f6f8fc;
    --line: #e7ecf4;
    --panel: #ffffff;
    --deep: #111827;
    --radius: 24px;
    --shadow: 0 18px 46px rgba(37, 68, 159, 0.12);
}
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: 1.75;
    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;
}
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,0.94);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--line);
}
.header-inner {
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand, .footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: var(--deep);
    letter-spacing: 0.02em;
}
.logo-img, .footer-brand img {
    width: 38px;
    height: 38px;
    object-fit: cover;
    border-radius: 12px;
}
.main-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 68px;
    display: none;
    flex-direction: column;
    padding: 16px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 20px;
    box-shadow: var(--shadow);
}
.main-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #344054;
    font-size: 14px;
}
.main-nav a:hover, .main-nav a.active {
    background: #eef5ff;
    color: var(--primary);
}
.nav-toggle {
    display: none;
}
.nav-toggle-label {
    display: inline-flex;
    width: 44px;
    height: 44px;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 5px;
    border-radius: 14px;
    background: #eef5ff;
    cursor: pointer;
}
.nav-toggle-label span {
    width: 20px;
    height: 2px;
    background: var(--primary);
    border-radius: 999px;
}
.nav-toggle:checked ~ .main-nav {
    display: flex;
}
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 26px;
    border-radius: 999px;
    background: #2980FE;
    color: #fff;
    font-weight: 700;
    box-shadow: 0 14px 26px rgba(41,128,254,0.25);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}
.download-btn:hover {
    background: #1768E8;
    transform: translateY(-2px);
    box-shadow: 0 18px 34px rgba(23,104,232,0.28);
}
.section {
    padding: 72px 0;
}
.section-light {
    background: var(--light);
}
.section-title {
    margin: 0 0 14px;
    font-size: clamp(28px, 5vw, 44px);
    line-height: 1.2;
    color: var(--deep);
}
.section-lead {
    margin: 0 0 28px;
    color: var(--muted);
    max-width: 760px;
}
.badge, .page-badge, .mini-tag {
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    color: var(--primary);
    background: #eef5ff;
    border: 1px solid #d9e8ff;
    font-weight: 700;
    font-size: 13px;
    padding: 5px 12px;
}
.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #fff;
    background: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
}
.vpn-network-hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 18% 20%, rgba(255,255,255,.25), transparent 22%),
        radial-gradient(circle at 78% 40%, rgba(255,255,255,.18), transparent 18%),
        linear-gradient(135deg, transparent 0 32%, rgba(255,255,255,.12) 33% 34%, transparent 35% 100%);
    opacity: .8;
}
.hero-grid {
    position: relative;
    display: grid;
    grid-template-columns: 1fr;
    gap: 36px;
    padding: 76px 0 84px;
    align-items: center;
}
.hero-content h1 {
    margin: 14px 0 18px;
    font-size: clamp(36px, 9vw, 64px);
    line-height: 1.08;
    letter-spacing: -0.04em;
}
.hero-content p {
    margin: 0 0 24px;
    color: rgba(255,255,255,.88);
    max-width: 620px;
    font-size: 17px;
}
.hero-tags, .status-tags, .inline-links, .tag-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}
.hero-tags span, .status-tags span {
    padding: 7px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,.16);
    border: 1px solid rgba(255,255,255,.28);
    color: #fff;
    font-size: 13px;
}
.hero-visual {
    position: relative;
    min-height: 310px;
}
.hero-card {
    position: relative;
    padding: 18px;
    border-radius: 32px;
    background: rgba(255,255,255,.16);
    border: 1px solid rgba(255,255,255,.24);
    box-shadow: 0 28px 80px rgba(30, 31, 70, .24);
}
.hero-card img {
    width: 100%;
    max-height: 420px;
    object-fit: contain;
    border-radius: 24px;
}
.floating-status {
    position: absolute;
    background: rgba(255,255,255,.95);
    color: #1f2937;
    border: 1px solid rgba(255,255,255,.65);
    box-shadow: 0 16px 34px rgba(21,32,80,.18);
    padding: 10px 14px;
    border-radius: 16px;
    font-weight: 700;
    font-size: 13px;
}
.status-a { left: 6px; top: 24px; }
.status-b { right: 0; top: 84px; }
.status-c { left: 22px; bottom: 48px; }
.status-d { right: 22px; bottom: 18px; }
.node-overview {
    margin-top: -46px;
    position: relative;
    z-index: 2;
}
.node-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}
.node-card, .feature-card, .risk-card, .faq-item, .info-card, .step-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: 0 14px 38px rgba(17,24,39,.06);
}
.node-card h3, .feature-card h3, .info-card h3, .risk-card h3, .step-card h3 {
    margin: 10px 0 8px;
    color: var(--deep);
    line-height: 1.3;
}
.node-card p, .feature-card p, .info-card p, .risk-card p, .step-card p, .faq-item p {
    margin: 0;
    color: var(--muted);
}
.card-link, .text-link {
    display: inline-flex;
    margin-top: 14px;
    color: var(--primary);
    font-weight: 700;
}
.split-section, .vpn-connection-section, .global-nodes-section, .high-speed-section, .privacy-protection-section, .multi-device-section, .encryption-protocol-section {
    display: grid;
    grid-template-columns: 1fr;
    gap: 28px;
    align-items: center;
}
.visual-panel {
    position: relative;
    overflow: hidden;
    border-radius: 32px;
    background: #f2f6ff;
    border: 1px solid var(--line);
    padding: 20px;
    box-shadow: var(--shadow);
}
.visual-panel img {
    width: 100%;
    max-height: 420px;
    object-fit: contain;
    border-radius: 24px;
}
.points {
    display: grid;
    gap: 12px;
    margin: 22px 0;
    padding: 0;
    list-style: none;
}
.points li {
    padding: 14px 16px;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: #fff;
    color: #475467;
}
.map-panel {
    background:
        radial-gradient(circle at 20% 30%, rgba(41,128,254,.16), transparent 24%),
        radial-gradient(circle at 75% 55%, rgba(123,78,241,.15), transparent 26%),
        #f7f9ff;
}
.map-dots {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    margin-top: 18px;
}
.map-dots span, .speed-line, .protocol-row {
    padding: 12px 14px;
    border-radius: 16px;
    background: rgba(255,255,255,.78);
    border: 1px solid var(--line);
    color: #344054;
}
.speed-card {
    display: grid;
    gap: 12px;
    margin-top: 20px;
}
.speed-line {
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.speed-line em {
    width: 46%;
    height: 8px;
    border-radius: 999px;
    background: linear-gradient(90deg, #d9e8ff, #2980FE);
}
.privacy-panel, .safety-panel, .protocol-panel {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 24px;
    box-shadow: var(--shadow);
}
.privacy-panel img, .protocol-panel img {
    margin-top: 18px;
    border-radius: 22px;
}
.no-log-policy-section .feature-grid, .feature-grid, .risk-grid, .faq-grid, .article-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
}
.process-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    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: 25px;
    width: 36px;
    height: 36px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    color: #fff;
    background: var(--primary);
    font-weight: 800;
}
.risk-card {
    border-left: 4px solid var(--primary);
}
.faq-item h3 {
    margin: 0 0 10px;
    color: var(--deep);
}
.cta-section {
    padding: 72px 0;
    color: #fff;
    background: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    text-align: center;
}
.cta-section p {
    max-width: 680px;
    margin: 0 auto 24px;
    color: rgba(255,255,255,.88);
}
.page-hero {
    background: linear-gradient(180deg, #f6f8ff 0%, #fff 100%);
    padding: 58px 0 32px;
}
.page-hero h1 {
    margin: 14px 0 14px;
    font-size: clamp(32px, 7vw, 54px);
    line-height: 1.15;
    color: var(--deep);
}
.page-hero p {
    color: var(--muted);
    max-width: 760px;
    margin: 0;
}
.article-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 42px 0 72px;
}
.article-main {
    min-width: 0;
}
.article-main h2 {
    color: var(--deep);
    margin-top: 0;
}
.article-main p {
    color: #475467;
}
.sidebar-card {
    background: #f7f9ff;
    border: 1px solid var(--line);
    border-radius: 24px;
    padding: 22px;
    position: sticky;
    top: 92px;
}
.check-list, .number-list {
    display: grid;
    gap: 12px;
    margin: 18px 0 0;
    padding: 0;
    list-style: none;
}
.check-list li, .number-list li {
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 16px;
    padding: 14px 16px;
    color: #475467;
}
.download-panel {
    margin-top: 24px;
    padding: 26px;
    background: #f6f8fc;
    border: 1px solid var(--line);
    border-radius: 28px;
}
.download-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    margin-top: 28px;
}
.site-footer {
    background: #101828;
    color: rgba(255,255,255,.76);
    padding: 56px 0 24px;
}
.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 26px;
}
.footer-brand {
    color: #fff;
}
.site-footer h3 {
    color: #fff;
    margin: 0 0 12px;
}
.site-footer a {
    display: block;
    margin: 8px 0;
    color: rgba(255,255,255,.72);
}
.site-footer a:hover {
    color: #fff;
}
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.12);
    margin-top: 34px;
    padding-top: 18px;
    font-size: 14px;
}
@media (min-width: 700px) {
    .node-grid, .feature-grid, .risk-grid, .faq-grid, .download-steps {
        grid-template-columns: repeat(2, 1fr);
    }
    .hero-grid, .split-section, .vpn-connection-section, .global-nodes-section, .high-speed-section, .privacy-protection-section, .multi-device-section, .encryption-protocol-section {
        grid-template-columns: minmax(0,1fr) minmax(0,1fr);
    }
    .process-steps {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-grid {
        grid-template-columns: 1.5fr 1fr 1fr 1fr;
    }
}
@media (min-width: 980px) {
    .nav-toggle-label {
        display: none;
    }
    .main-nav {
        position: static;
        display: flex;
        flex-direction: row;
        padding: 0;
        background: transparent;
        border: 0;
        box-shadow: none;
        align-items: center;
        gap: 2px;
    }
    .main-nav a {
        padding: 8px 10px;
        white-space: nowrap;
    }
    .hero-grid {
        grid-template-columns: 1.04fr .96fr;
        padding: 92px 0 112px;
    }
    .node-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    .risk-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-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}
@media (max-width: 420px) {
    .container {
        width: min(100% - 24px, 1120px);
    }
    .section {
        padding: 54px 0;
    }
    .download-btn {
        width: 100%;
    }
    .floating-status {
        position: static;
        display: inline-flex;
        margin: 8px 6px 0 0;
    }
}