* {
    box-sizing: border-box;
}

:root {
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #202A3A;
    --muted: #667085;
    --light: #F4F7FB;
    --line: #E5EAF2;
    --card: #FFFFFF;
    --deep: #10223F;
    --radius-lg: 28px;
    --radius-md: 20px;
    --shadow: 0 18px 45px rgba(36, 67, 124, 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: #FFFFFF;
    line-height: 1.7;
    overflow-x: hidden;
}

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

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

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

h1, h2, h3, h4 {
    margin: 0 0 14px;
    color: var(--deep);
    line-height: 1.22;
}

h1 {
    font-size: clamp(34px, 8vw, 64px);
    letter-spacing: -1.6px;
}

h2 {
    font-size: clamp(26px, 4.6vw, 42px);
    letter-spacing: -0.8px;
}

h3 {
    font-size: 20px;
}

.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(16px);
    border-bottom: 1px solid rgba(229,234,242,0.9);
}

.nav-shell {
    width: min(1180px, calc(100% - 28px));
    margin: 0 auto;
    min-height: 72px;
    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: -0.3px;
}

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

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

.site-nav a {
    display: block;
    padding: 12px 14px;
    color: #3B475D;
    font-weight: 650;
    border-radius: 14px;
}

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

.nav-toggle {
    display: none;
}

.nav-toggle-label {
    display: inline-flex;
    flex-direction: column;
    gap: 5px;
    width: 44px;
    height: 44px;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: #FFFFFF;
}

.nav-toggle-label span {
    width: 20px;
    height: 2px;
    border-radius: 3px;
    background: var(--deep);
}

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

.gradient-bg,
.vpn-network-hero,
.cta-section {
    background: var(--gradient);
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #FFFFFF;
    padding: 58px 0 52px;
}

.vpn-network-hero::before,
.vpn-network-hero::after,
.global-nodes-section::before {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    opacity: 0.28;
    background-image:
        radial-gradient(circle at 12% 22%, rgba(255,255,255,0.9) 0 2px, transparent 3px),
        radial-gradient(circle at 68% 18%, rgba(255,255,255,0.8) 0 2px, transparent 3px),
        radial-gradient(circle at 44% 72%, rgba(255,255,255,0.6) 0 2px, transparent 3px),
        linear-gradient(115deg, transparent 0 18%, rgba(255,255,255,0.26) 18.2% 18.6%, transparent 18.8% 100%),
        linear-gradient(28deg, transparent 0 32%, rgba(255,255,255,0.2) 32.1% 32.5%, transparent 32.7% 100%);
}

.hero-grid {
    position: relative;
    z-index: 2;
    display: grid;
    gap: 34px;
    align-items: center;
}

.hero-copy h1,
.hero-copy p {
    color: #FFFFFF;
}

.hero-copy p {
    max-width: 650px;
    font-size: 17px;
    color: rgba(255,255,255,0.88);
}

.hero-tags,
.status-row,
.badge-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 18px 0 24px;
}

.hero-tags span,
.status-row span,
.badge,
.category-badge {
    display: inline-flex;
    align-items: center;
    min-height: 32px;
    padding: 6px 12px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 750;
}

.hero-tags span {
    color: #FFFFFF;
    background: rgba(255,255,255,0.16);
    border: 1px solid rgba(255,255,255,0.28);
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 26px;
    border-radius: 999px;
    color: #FFFFFF;
    background: var(--blue);
    font-weight: 800;
    box-shadow: 0 14px 30px rgba(41,128,254,0.28);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    background: var(--blue-dark);
    transform: translateY(-2px);
    box-shadow: 0 18px 36px rgba(23,104,232,0.32);
}

.hero-visual {
    position: relative;
    min-height: 340px;
    display: grid;
    place-items: center;
}

.hero-visual .visual-card {
    width: min(420px, 92%);
    padding: 18px;
    border-radius: 32px;
    background: rgba(255,255,255,0.16);
    border: 1px solid rgba(255,255,255,0.24);
    backdrop-filter: blur(18px);
    box-shadow: 0 30px 60px rgba(18, 31, 78, 0.2);
}

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

.float-label {
    position: absolute;
    padding: 10px 14px;
    border-radius: 16px;
    background: rgba(255,255,255,0.94);
    color: var(--deep);
    font-weight: 800;
    font-size: 13px;
    box-shadow: var(--shadow);
}

.float-label.one { top: 10%; left: 2%; }
.float-label.two { top: 16%; right: 0; }
.float-label.three { bottom: 19%; left: 0; }
.float-label.four { bottom: 10%; right: 5%; }

.section {
    padding: 64px 0;
}

.section.light,
.high-speed-section,
.process-section,
.page-hero {
    background: #F6F8FC;
}

.section-heading {
    max-width: 760px;
    margin-bottom: 28px;
}

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

.section-kicker,
.category-badge {
    color: var(--blue);
    background: #EEF5FF;
    border: 1px solid #D7E7FF;
}

.node-overview {
    margin-top: -28px;
    position: relative;
    z-index: 4;
}

.node-overview-grid,
.card-grid,
.no-log-grid,
.risk-grid,
.faq-grid,
.feature-grid {
    display: grid;
    gap: 18px;
}

.node-card,
.info-card,
.risk-card,
.faq-item,
.step-card,
.download-step,
.tip-card,
.policy-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    padding: 22px;
    box-shadow: 0 12px 34px rgba(42, 64, 104, 0.06);
}

.node-card .label,
.info-card .label,
.policy-card .label {
    display: inline-flex;
    color: var(--blue);
    font-weight: 850;
    font-size: 13px;
    margin-bottom: 10px;
}

.text-link,
.inline-link {
    color: var(--blue);
    font-weight: 800;
}

.text-link:hover,
.inline-link:hover {
    color: var(--blue-dark);
}

.split-section,
.vpn-connection-section,
.global-layout,
.high-speed-layout,
.privacy-layout,
.multi-device-layout,
.tech-layout,
.about-layout,
.page-layout,
.download-layout {
    display: grid;
    gap: 28px;
    align-items: center;
}

.image-panel,
.network-panel,
.security-panel,
.device-panel,
.protocol-panel {
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-lg);
    border: 1px solid var(--line);
    background: #FFFFFF;
    padding: 20px;
    box-shadow: var(--shadow);
}

.image-panel img,
.network-panel img,
.device-panel img,
.protocol-panel img {
    border-radius: 22px;
    width: 100%;
}

.feature-list,
.clean-list,
.check-list,
.timeline-list {
    list-style: none;
    padding: 0;
    margin: 18px 0 0;
    display: grid;
    gap: 12px;
}

.feature-list li,
.clean-list li,
.check-list li,
.timeline-list li {
    position: relative;
    padding-left: 26px;
    color: #445269;
}

.feature-list li::before,
.clean-list li::before,
.check-list li::before,
.timeline-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 #EAF3FF;
}

.global-nodes-section {
    position: relative;
    overflow: hidden;
    background: #F7FAFF;
}

.global-nodes-section::before {
    opacity: 0.12;
    background-image:
        radial-gradient(circle at 20% 30%, #2980FE 0 3px, transparent 4px),
        radial-gradient(circle at 72% 22%, #7B4EF1 0 3px, transparent 4px),
        radial-gradient(circle at 56% 68%, #B84DDA 0 3px, transparent 4px),
        linear-gradient(35deg, transparent 0 25%, #2980FE 25.1% 25.4%, transparent 25.6% 100%),
        linear-gradient(145deg, transparent 0 35%, #7B4EF1 35.1% 35.4%, transparent 35.6% 100%);
}

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

.node-pill {
    padding: 14px;
    border-radius: 18px;
    background: #FFFFFF;
    border-left: 4px solid var(--blue);
    box-shadow: 0 10px 28px rgba(42, 64, 104, 0.07);
}

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

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

.speed-line strong {
    display: block;
    color: var(--deep);
}

.bar {
    height: 8px;
    border-radius: 999px;
    margin-top: 10px;
    background: linear-gradient(90deg, #2980FE, #A8CFFF);
}

.bar.medium { width: 74%; }
.bar.long { width: 88%; }
.bar.short { width: 58%; }

.privacy-protection-section {
    background: #FFFFFF;
}

.security-panel {
    background: linear-gradient(180deg, #FFFFFF 0%, #F7FAFF 100%);
}

.security-row {
    display: flex;
    justify-content: space-between;
    gap: 14px;
    padding: 16px 0;
    border-bottom: 1px solid var(--line);
}

.security-row:last-child {
    border-bottom: 0;
}

.security-row span {
    color: var(--muted);
}

.no-log-policy-section {
    background: #F6F8FC;
}

.no-log-grid .info-card {
    border-top: 4px solid var(--blue);
}

.device-card-stack {
    display: grid;
    gap: 14px;
}

.device-chip {
    padding: 16px;
    border-radius: 18px;
    background: #F4F8FF;
    border: 1px solid #DDEBFF;
    font-weight: 800;
    color: var(--deep);
}

.protocol-panel {
    background: #10223F;
    color: #FFFFFF;
    border: 0;
}

.protocol-panel h3,
.protocol-panel p {
    color: #FFFFFF;
}

.protocol-row {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    padding: 16px;
    margin-top: 12px;
    border-radius: 18px;
    background: rgba(255,255,255,0.08);
    border: 1px solid rgba(255,255,255,0.14);
}

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

.step-card {
    position: relative;
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    border-radius: 14px;
    background: var(--blue);
    color: #FFFFFF;
    font-weight: 900;
    margin-bottom: 12px;
}

.risk-grid {
    align-items: stretch;
}

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

.risk-card strong {
    display: block;
    color: var(--deep);
    margin-bottom: 8px;
}

.faq-item h3 {
    font-size: 18px;
}

.cta-section {
    position: relative;
    overflow: hidden;
    margin: 40px 0 0;
    padding: 62px 0;
    color: #FFFFFF;
    text-align: center;
}

.cta-section h2,
.cta-section p {
    color: #FFFFFF;
}

.cta-section p {
    max-width: 680px;
    margin: 0 auto 24px;
    color: rgba(255,255,255,0.86);
}

.page-hero {
    padding: 58px 0 38px;
}

.page-hero .container {
    display: grid;
    gap: 14px;
}

.page-hero p {
    max-width: 760px;
    font-size: 17px;
}

.page-content {
    padding: 48px 0 72px;
}

.page-layout {
    align-items: start;
}

.article-card,
.sidebar-card,
.download-card {
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    padding: 26px;
    box-shadow: 0 14px 36px rgba(42,64,104,0.07);
}

.article-card h2 {
    font-size: 28px;
}

.sidebar-card {
    position: sticky;
    top: 96px;
}

.sidebar-card h3 {
    color: var(--blue);
}

.panel-note {
    padding: 18px;
    border-radius: 20px;
    background: #F4F8FF;
    border: 1px solid #DDEBFF;
    margin: 18px 0;
}

.download-layout {
    align-items: start;
}

.download-card {
    text-align: center;
}

.download-steps {
    display: grid;
    gap: 14px;
    margin-top: 22px;
}

.download-step strong {
    display: block;
    color: var(--deep);
}

.about-stat-grid {
    display: grid;
    gap: 16px;
    margin-top: 22px;
}

.about-stat {
    padding: 18px;
    border-radius: 20px;
    background: #F7FAFF;
    border: 1px solid #DDEBFF;
}

.site-footer {
    background: #0F213D;
    color: #B8C4D8;
    padding: 46px 0 0;
}

.site-footer p,
.site-footer a {
    color: #B8C4D8;
}

.site-footer h3 {
    color: #FFFFFF;
    font-size: 16px;
}

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

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

.footer-brand {
    color: #FFFFFF;
    margin-bottom: 12px;
}

.footer-bottom {
    margin-top: 34px;
    padding: 18px;
    text-align: center;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: #91A1BA;
    font-size: 14px;
}

@media (min-width: 680px) {
    .node-overview-grid,
    .card-grid,
    .risk-grid,
    .faq-grid,
    .feature-grid,
    .download-steps,
    .about-stat-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
    .process-steps {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (min-width: 960px) {
    .nav-toggle-label {
        display: none;
    }
    .site-nav {
        position: static;
        display: flex;
        align-items: center;
        gap: 2px;
        padding: 0;
        background: transparent;
        border: 0;
        box-shadow: none;
    }
    .site-nav a {
        display: inline-flex;
        padding: 10px 11px;
        font-size: 14px;
    }
    .hero-grid,
    .vpn-connection-section,
    .global-layout,
    .high-speed-layout,
    .privacy-layout,
    .multi-device-layout,
    .tech-layout,
    .about-layout,
    .download-layout {
        grid-template-columns: 1.05fr .95fr;
    }
    .page-layout {
        grid-template-columns: minmax(0, 1fr) 330px;
    }
    .node-overview-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
    .no-log-grid,
    .risk-grid,
    .footer-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
    .process-steps {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
    .section {
        padding: 86px 0;
    }
    .vpn-network-hero {
        padding: 86px 0 92px;
    }
}

@media (max-width: 520px) {
    .container,
    .nav-shell {
        width: min(100% - 24px, 1120px);
    }
    .download-btn {
        width: 100%;
    }
    .float-label {
        display: none;
    }
    .hero-visual {
        min-height: 250px;
    }
    .article-card,
    .sidebar-card,
    .download-card {
        padding: 20px;
        border-radius: 22px;
    }
}