* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    color: #263142;
    background: #f7f9fc;
    line-height: 1.7;
}

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, 0.96);
    border-bottom: 1px solid #e8edf5;
    backdrop-filter: blur(14px);
}

.header-inner {
    width: min(1180px, calc(100% - 28px));
    min-height: 68px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #18263b;
    white-space: nowrap;
}

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

.brand-name {
    font-size: 18px;
    letter-spacing: 0.02em;
}

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

.site-nav a {
    padding: 10px 12px;
    border-radius: 999px;
    color: #4b5b73;
    font-size: 14px;
    font-weight: 600;
    transition: background 0.2s ease, color 0.2s ease;
}

.site-nav a:hover {
    background: #edf4ff;
    color: #2980FE;
}

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

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: #2980FE;
    color: #ffffff;
    font-weight: 800;
    letter-spacing: 0.01em;
    box-shadow: 0 14px 28px rgba(41, 128, 254, 0.25);
    transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.download-btn:hover {
    background: #1768E8;
    transform: translateY(-2px);
    box-shadow: 0 18px 34px rgba(23, 104, 232, 0.28);
}

.gradient-bg,
.vpn-network-hero,
.cta-section {
    background: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #ffffff;
    padding: 64px 0 46px;
}

.vpn-network-hero::before,
.vpn-network-hero::after {
    content: "";
    position: absolute;
    border-radius: 999px;
    pointer-events: none;
}

.vpn-network-hero::before {
    width: 520px;
    height: 520px;
    right: -160px;
    top: -180px;
    background: rgba(255, 255, 255, 0.16);
}

.vpn-network-hero::after {
    width: 360px;
    height: 360px;
    left: -140px;
    bottom: -160px;
    background: rgba(255, 255, 255, 0.11);
}

.hero-network-lines {
    position: absolute;
    inset: 0;
    opacity: 0.22;
    background-image:
        radial-gradient(circle at 18% 22%, #fff 0 2px, transparent 3px),
        radial-gradient(circle at 46% 32%, #fff 0 2px, transparent 3px),
        radial-gradient(circle at 74% 24%, #fff 0 2px, transparent 3px),
        radial-gradient(circle at 28% 76%, #fff 0 2px, transparent 3px),
        radial-gradient(circle at 67% 72%, #fff 0 2px, transparent 3px),
        linear-gradient(120deg, transparent 0%, rgba(255,255,255,0.5) 48%, transparent 49%);
}

.hero-grid {
    position: relative;
    z-index: 1;
    display: grid;
    gap: 34px;
    align-items: center;
}

.hero-copy h1 {
    margin: 0 0 18px;
    font-size: clamp(34px, 8vw, 62px);
    line-height: 1.08;
    letter-spacing: -0.04em;
}

.hero-copy p {
    margin: 0 0 24px;
    color: rgba(255, 255, 255, 0.88);
    font-size: 17px;
    max-width: 650px;
}

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

.hero-tags span,
.status-tags span,
.inline-tags span {
    display: inline-flex;
    align-items: center;
    padding: 7px 12px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 700;
}

.hero-tags span {
    background: rgba(255, 255, 255, 0.16);
    border: 1px solid rgba(255, 255, 255, 0.22);
}

.hero-visual {
    position: relative;
    min-height: 300px;
    display: grid;
    place-items: center;
}

.hero-device {
    position: relative;
    width: min(430px, 88vw);
    padding: 22px;
    border-radius: 32px;
    background: rgba(255, 255, 255, 0.18);
    border: 1px solid rgba(255, 255, 255, 0.26);
    box-shadow: 0 26px 60px rgba(26, 37, 101, 0.26);
}

.hero-device img {
    border-radius: 26px;
    background: rgba(255,255,255,0.12);
}

.floating-label {
    position: absolute;
    padding: 10px 14px;
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.92);
    color: #1e2a3d;
    font-weight: 800;
    font-size: 13px;
    box-shadow: 0 14px 28px rgba(38, 49, 66, 0.16);
}

.label-safe { top: 18px; left: -8px; }
.label-node { right: -8px; top: 72px; }
.label-fast { left: 18px; bottom: 28px; }
.label-privacy { right: 20px; bottom: -4px; }

.section {
    padding: 58px 0;
}

.section-muted {
    background: #eef4fb;
}

.section-title {
    margin: 0 0 12px;
    font-size: clamp(28px, 5vw, 42px);
    line-height: 1.2;
    color: #172235;
    letter-spacing: -0.03em;
}

.section-lead {
    margin: 0;
    color: #637188;
    max-width: 760px;
}

.section-head {
    margin-bottom: 28px;
}

.node-overview {
    margin-top: -28px;
    position: relative;
    z-index: 3;
}

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

.node-card,
.info-card,
.risk-card,
.faq-item,
.step-card,
.policy-card,
.tip-card {
    background: #ffffff;
    border: 1px solid #e6ecf4;
    border-radius: 24px;
    box-shadow: 0 14px 36px rgba(23, 34, 53, 0.06);
}

.node-card {
    padding: 22px;
}

.node-card .tag,
.category-badge,
.blue-label {
    display: inline-flex;
    padding: 5px 10px;
    border-radius: 999px;
    background: #eaf3ff;
    color: #2980FE;
    font-size: 12px;
    font-weight: 800;
    margin-bottom: 12px;
}

.node-card h3,
.info-card h3,
.risk-card h3,
.step-card h3,
.policy-card h3,
.tip-card h3 {
    margin: 0 0 8px;
    color: #1c2a3d;
    line-height: 1.35;
}

.node-card p,
.info-card p,
.risk-card p,
.step-card p,
.policy-card p,
.tip-card p {
    margin: 0;
    color: #637188;
}

.text-link {
    display: inline-flex;
    margin-top: 14px;
    color: #2980FE;
    font-weight: 800;
}

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

.image-panel,
.security-panel,
.map-panel,
.speed-panel,
.tech-panel {
    position: relative;
    overflow: hidden;
    border-radius: 32px;
    background: #ffffff;
    border: 1px solid #e6ecf4;
    box-shadow: 0 22px 50px rgba(23, 34, 53, 0.08);
    padding: 18px;
}

.image-panel img,
.security-panel img,
.map-panel img,
.speed-panel img,
.tech-panel img {
    border-radius: 24px;
    width: 100%;
    object-fit: cover;
}

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

.feature-list li {
    padding: 14px 16px;
    border-left: 4px solid #2980FE;
    border-radius: 16px;
    background: #f3f7fc;
    color: #3c4a5f;
}

.map-panel {
    background:
        radial-gradient(circle at 20% 35%, rgba(41,128,254,0.15), transparent 22%),
        radial-gradient(circle at 75% 60%, rgba(123,78,241,0.16), transparent 24%),
        #ffffff;
}

.map-dots {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    margin-top: 16px;
}

.map-dots span,
.speed-line,
.protocol-row {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    padding: 12px 14px;
    border-radius: 16px;
    background: #f4f8fd;
    color: #42516a;
    font-weight: 700;
}

.speed-lines,
.protocol-list {
    display: grid;
    gap: 12px;
    margin-top: 16px;
}

.privacy-tags {
    display: grid;
    gap: 12px;
    margin-top: 18px;
}

.privacy-tags span {
    padding: 14px 16px;
    background: #f3f7fc;
    border-radius: 16px;
    color: #40506a;
    font-weight: 700;
}

.no-log-policy-section {
    display: grid;
    gap: 16px;
}

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

.device-grid,
.info-grid,
.risk-grid,
.faq-grid,
.process-steps {
    display: grid;
    gap: 16px;
}

.device-card {
    padding: 18px;
    border-radius: 22px;
    background: #ffffff;
    border: 1px solid #e6ecf4;
}

.device-card strong {
    display: block;
    color: #1d2b3f;
    margin-bottom: 6px;
}

.device-card p {
    margin: 0;
    color: #637188;
}

.process-steps {
    counter-reset: step;
}

.step-card {
    position: relative;
    padding: 22px 22px 22px 72px;
}

.step-number {
    position: absolute;
    left: 20px;
    top: 22px;
    width: 36px;
    height: 36px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    background: #2980FE;
    color: #ffffff;
    font-weight: 900;
}

.risk-card {
    padding: 22px;
    border-left: 4px solid #2980FE;
}

.risk-card .suggestion {
    margin-top: 12px;
    padding: 12px;
    border-radius: 14px;
    background: #f2f7ff;
    color: #40506a;
}

.faq-item {
    padding: 22px;
}

.faq-item h3 {
    margin: 0 0 8px;
    color: #19283d;
}

.faq-item p {
    margin: 0;
    color: #637188;
}

.cta-section {
    color: #ffffff;
    text-align: center;
    padding: 58px 0;
    position: relative;
    overflow: hidden;
}

.cta-section h2 {
    margin: 0 0 12px;
    font-size: clamp(28px, 5vw, 44px);
}

.cta-section p {
    margin: 0 auto 22px;
    max-width: 720px;
    color: rgba(255,255,255,0.88);
}

.page-hero {
    padding: 54px 0 34px;
    background:
        radial-gradient(circle at 85% 20%, rgba(123,78,241,0.16), transparent 32%),
        linear-gradient(180deg, #ffffff 0%, #eef4fb 100%);
}

.page-hero-inner {
    display: grid;
    gap: 18px;
}

.page-hero h1 {
    margin: 0;
    font-size: clamp(32px, 6vw, 52px);
    line-height: 1.14;
    color: #172235;
    letter-spacing: -0.035em;
}

.page-hero p {
    margin: 0;
    color: #637188;
    max-width: 780px;
    font-size: 17px;
}

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

.article-card {
    background: #ffffff;
    border: 1px solid #e6ecf4;
    border-radius: 28px;
    padding: 24px;
    box-shadow: 0 18px 42px rgba(23, 34, 53, 0.06);
}

.article-card h2 {
    margin: 0 0 12px;
    color: #172235;
    font-size: 26px;
}

.article-card p {
    color: #516178;
    margin: 0 0 16px;
}

.article-card p:last-child {
    margin-bottom: 0;
}

.side-panel {
    display: grid;
    gap: 14px;
}

.check-list,
.number-list {
    margin: 0;
    padding-left: 20px;
    color: #516178;
}

.check-list li,
.number-list li {
    margin: 8px 0;
}

.download-area {
    margin-top: 22px;
}

.download-page-panel {
    max-width: 880px;
    margin: 0 auto;
    text-align: center;
}

.download-steps {
    text-align: left;
    margin-top: 26px;
}

.site-footer {
    background: #111b2c;
    color: #cbd5e1;
    padding: 48px 0 22px;
}

.footer-grid {
    display: grid;
    gap: 24px;
}

.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: #ffffff;
    margin-bottom: 12px;
}

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

.site-footer p {
    margin: 0;
    color: #aab7c8;
}

.site-footer a {
    display: block;
    color: #aab7c8;
    margin: 8px 0;
}

.site-footer a:hover {
    color: #ffffff;
}

.footer-bottom {
    margin-top: 30px;
    padding-top: 18px;
    border-top: 1px solid rgba(255,255,255,0.12);
    color: #91a0b5;
    font-size: 14px;
}

@media (max-width: 820px) {
    .header-inner {
        min-height: 64px;
    }

    .nav-toggle-label {
        display: flex;
        width: 42px;
        height: 42px;
        align-items: center;
        justify-content: center;
        border-radius: 14px;
        border: 1px solid #e1e8f2;
        cursor: pointer;
    }

    .nav-toggle-label span,
    .nav-toggle-label span::before,
    .nav-toggle-label span::after {
        display: block;
        width: 20px;
        height: 2px;
        border-radius: 999px;
        background: #263142;
        position: relative;
        content: "";
    }

    .nav-toggle-label span::before {
        position: absolute;
        top: -7px;
    }

    .nav-toggle-label span::after {
        position: absolute;
        top: 7px;
    }

    .site-nav {
        position: absolute;
        left: 14px;
        right: 14px;
        top: 64px;
        display: none;
        flex-direction: column;
        align-items: stretch;
        padding: 12px;
        border-radius: 20px;
        background: #ffffff;
        border: 1px solid #e6ecf4;
        box-shadow: 0 18px 42px rgba(23, 34, 53, 0.14);
    }

    .site-nav a {
        border-radius: 14px;
        padding: 12px 14px;
    }

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

    .floating-label {
        position: static;
        margin: 8px;
        display: inline-flex;
    }

    .hero-visual {
        display: block;
    }

    .hero-device {
        margin: 0 auto 8px;
    }
}

@media (min-width: 640px) {
    .node-grid,
    .risk-grid,
    .faq-grid,
    .info-grid,
    .device-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

@media (min-width: 900px) {
    .hero-grid {
        grid-template-columns: 1.02fr 0.98fr;
    }

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

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

    .no-log-policy-section {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

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

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

    .content-layout {
        grid-template-columns: minmax(0, 1fr) 320px;
    }

    .article-card {
        padding: 34px;
    }
}

@media (min-width: 1100px) {
    .process-steps {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}