* {
    box-sizing: border-box;
}

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: #202a3a;
    background: #f6f8fc;
    line-height: 1.75;
    overflow-x: hidden;
}

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

img {
    max-width: 100%;
    height: auto;
    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(16px);
    border-bottom: 1px solid #e6ebf5;
}

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

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #14213d;
    letter-spacing: 0.02em;
}

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

.site-nav {
    display: none;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    padding: 12px 16px 18px;
    background: #ffffff;
    border-bottom: 1px solid #e6ebf5;
    box-shadow: 0 18px 40px rgba(35, 55, 90, 0.08);
}

.site-nav a {
    display: block;
    padding: 12px 10px;
    border-radius: 14px;
    color: #526073;
    font-weight: 650;
}

.site-nav a:hover,
.site-nav a.active {
    color: #2980fe;
    background: #eef5ff;
}

.nav-toggle {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.nav-toggle-label {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 42px;
    height: 42px;
    border: 1px solid #e5eaf3;
    border-radius: 14px;
    padding: 0 10px;
    cursor: pointer;
    background: #fff;
}

.nav-toggle-label span {
    height: 2px;
    background: #25334d;
    border-radius: 3px;
}

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

.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;
    box-shadow: 0 14px 30px rgba(41, 128, 254, 0.26);
    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);
}

.section-eyebrow,
.badge {
    display: inline-flex;
    align-items: center;
    width: fit-content;
    padding: 6px 12px;
    border-radius: 999px;
    color: #2980fe;
    background: #edf5ff;
    font-size: 0.86rem;
    font-weight: 750;
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #ffffff;
    background: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
}

.vpn-network-hero::before,
.vpn-network-hero::after {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.vpn-network-hero::before {
    background:
        radial-gradient(circle at 18% 28%, rgba(255, 255, 255, 0.22), transparent 18%),
        radial-gradient(circle at 76% 22%, rgba(255, 255, 255, 0.16), transparent 20%),
        linear-gradient(135deg, rgba(255,255,255,.14) 1px, transparent 1px);
    background-size: auto, auto, 38px 38px;
    opacity: 0.88;
}

.vpn-network-hero::after {
    background:
        linear-gradient(110deg, transparent 10%, rgba(255,255,255,.16) 10.4%, transparent 10.8%),
        linear-gradient(26deg, transparent 36%, rgba(255,255,255,.12) 36.3%, transparent 36.8%);
    opacity: 0.7;
}

.hero-inner {
    position: relative;
    z-index: 1;
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    padding: 64px 0 56px;
    display: grid;
    gap: 32px;
    align-items: center;
}

.hero-copy h1 {
    margin: 16px 0 18px;
    font-size: clamp(2.2rem, 11vw, 4.7rem);
    line-height: 1.04;
    letter-spacing: -0.05em;
}

.hero-copy p {
    max-width: 650px;
    color: rgba(255,255,255,0.9);
    font-size: 1.05rem;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    align-items: center;
    margin-top: 26px;
}

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

.hero-tags span,
.floating-tags span {
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,0.16);
    border: 1px solid rgba(255,255,255,0.22);
    color: #fff;
    font-size: 0.92rem;
}

.hero-visual {
    position: relative;
    min-height: 360px;
    display: grid;
    place-items: center;
}

.hero-device {
    width: min(470px, 86vw);
    border-radius: 32px;
    filter: drop-shadow(0 28px 44px rgba(20, 25, 65, 0.28));
}

.status-card {
    position: absolute;
    display: flex;
    align-items: center;
    gap: 9px;
    padding: 10px 14px;
    color: #17223a;
    background: rgba(255,255,255,0.92);
    border: 1px solid rgba(255,255,255,0.7);
    border-radius: 18px;
    box-shadow: 0 18px 36px rgba(31, 42, 76, 0.18);
    font-weight: 750;
}

.status-card::before {
    content: "";
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #2980fe;
    box-shadow: 0 0 0 5px rgba(41,128,254,.12);
}

.status-one { top: 10%; left: 4%; }
.status-two { top: 18%; right: 0; }
.status-three { bottom: 19%; left: 0; }
.status-four { bottom: 8%; right: 8%; }

.section {
    padding: 58px 0;
}

.section-title {
    margin: 10px 0 14px;
    font-size: clamp(1.8rem, 6vw, 3rem);
    line-height: 1.18;
    letter-spacing: -0.03em;
    color: #16233b;
}

.section-lead {
    max-width: 760px;
    color: #607086;
    margin: 0 0 26px;
}

.node-overview {
    margin-top: -24px;
    position: relative;
    z-index: 2;
}

.node-grid,
.card-grid,
.risk-grid,
.faq-grid,
.policy-grid,
.device-grid,
.protocol-grid {
    display: grid;
    gap: 18px;
}

.node-card,
.feature-card,
.risk-card,
.faq-item,
.policy-card,
.step-card,
.info-card,
.tip-box,
.sidebar-card {
    background: #ffffff;
    border: 1px solid #e5ebf5;
    border-radius: 24px;
    padding: 22px;
    box-shadow: 0 16px 38px rgba(28, 45, 80, 0.06);
}

.node-card span {
    display: inline-flex;
    color: #2980fe;
    background: #edf5ff;
    padding: 5px 10px;
    border-radius: 999px;
    font-weight: 780;
    font-size: 0.82rem;
}

.node-card h3,
.feature-card h3,
.risk-card h3,
.policy-card h3,
.step-card h3,
.info-card h3,
.sidebar-card h3 {
    margin: 14px 0 8px;
    color: #17233b;
    line-height: 1.35;
}

.node-card p,
.feature-card p,
.risk-card p,
.policy-card p,
.step-card p,
.info-card p,
.sidebar-card p,
.faq-item p {
    color: #65758a;
    margin: 0;
}

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

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

.visual-panel {
    position: relative;
    background: #ffffff;
    border: 1px solid #e5ebf5;
    border-radius: 32px;
    padding: 20px;
    overflow: hidden;
    box-shadow: 0 18px 42px rgba(27, 43, 78, 0.08);
}

.visual-panel::before {
    content: "";
    position: absolute;
    inset: auto -10% -20% 20%;
    height: 48%;
    background: linear-gradient(90deg, rgba(53,88,242,.12), rgba(184,77,218,.12));
    filter: blur(24px);
}

.visual-panel img {
    position: relative;
    z-index: 1;
    border-radius: 24px;
    margin: 0 auto;
}

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

.feature-list li,
.check-list li,
.link-list li {
    position: relative;
    padding-left: 24px;
    color: #56677d;
}

.feature-list li::before,
.check-list li::before,
.link-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0.72em;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #2980fe;
}

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

.map-panel {
    position: relative;
    min-height: 330px;
    border-radius: 32px;
    background:
        radial-gradient(circle at 18% 28%, rgba(41,128,254,.18), transparent 12%),
        radial-gradient(circle at 76% 22%, rgba(123,78,241,.16), transparent 14%),
        radial-gradient(circle at 58% 72%, rgba(184,77,218,.14), transparent 13%),
        linear-gradient(135deg, #f4f8ff 0%, #ffffff 100%);
    border: 1px solid #e2eafa;
    padding: 24px;
    display: grid;
    align-content: end;
    overflow: hidden;
}

.map-panel::before {
    content: "";
    position: absolute;
    inset: 30px;
    border-radius: 28px;
    background:
        linear-gradient(24deg, transparent 42%, rgba(41,128,254,.22) 42.2%, transparent 42.8%),
        linear-gradient(154deg, transparent 35%, rgba(123,78,241,.18) 35.2%, transparent 35.8%),
        linear-gradient(96deg, transparent 52%, rgba(184,77,218,.15) 52.2%, transparent 52.8%);
}

.map-card {
    position: relative;
    z-index: 1;
    background: rgba(255,255,255,0.9);
    border: 1px solid #e4ebf6;
    border-radius: 24px;
    padding: 18px;
    box-shadow: 0 18px 40px rgba(27, 43, 78, 0.08);
}

.high-speed-section {
    background: #eef5ff;
}

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

.speed-line {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    padding: 14px 16px;
    border: 1px solid #dce8fb;
    border-radius: 18px;
    background: #ffffff;
}

.speed-line strong {
    color: #16233b;
}

.speed-line span {
    color: #6a7a90;
    font-size: 0.94rem;
}

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

.privacy-panel {
    background: linear-gradient(135deg, #ffffff 0%, #f4f8ff 100%);
    border: 1px solid #e4ebf6;
    border-radius: 32px;
    padding: 26px;
    box-shadow: 0 18px 40px rgba(24, 42, 76, 0.07);
}

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

.privacy-tags span {
    padding: 9px 12px;
    border-radius: 999px;
    color: #3558f2;
    background: #edf5ff;
    font-weight: 760;
}

.no-log-policy-section .policy-card {
    border-top: 4px solid #2980fe;
}

.multi-device-section {
    background: #ffffff;
}

.device-card {
    background: #f7faff;
    border: 1px solid #e4ebf6;
    border-radius: 24px;
    padding: 20px;
}

.encryption-protocol-section {
    background: #f6f8fc;
}

.protocol-panel {
    display: grid;
    gap: 16px;
    padding: 22px;
    border-radius: 30px;
    background: #101f42;
    color: #ffffff;
    overflow: hidden;
}

.protocol-panel p {
    color: rgba(255,255,255,.78);
}

.protocol-card {
    border: 1px solid rgba(255,255,255,.14);
    background: rgba(255,255,255,.08);
    border-radius: 22px;
    padding: 18px;
}

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

.step-card {
    position: relative;
    padding-top: 52px;
}

.step-card::before {
    counter-increment: step;
    content: counter(step, decimal-leading-zero);
    position: absolute;
    top: 18px;
    left: 22px;
    color: #2980fe;
    font-weight: 900;
    letter-spacing: 0.08em;
}

.risk-card {
    border-left: 4px solid #2980fe;
}

.risk-card .suggestion {
    display: block;
    margin-top: 10px;
    color: #202a3a;
    font-weight: 750;
}

.faq-item h3 {
    margin: 0 0 8px;
    color: #17233b;
}

.cta-section {
    margin: 40px 0 72px;
}

.cta-box {
    overflow: hidden;
    text-align: center;
    color: #ffffff;
    border-radius: 34px;
    padding: 42px 22px;
    background: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    box-shadow: 0 22px 48px rgba(63, 84, 218, 0.18);
}

.cta-box p {
    max-width: 680px;
    margin: 0 auto 22px;
    color: rgba(255,255,255,0.88);
}

.page-hero {
    padding: 58px 0 34px;
    background:
        radial-gradient(circle at 8% 20%, rgba(41,128,254,.12), transparent 24%),
        radial-gradient(circle at 88% 18%, rgba(184,77,218,.12), transparent 24%),
        #ffffff;
    border-bottom: 1px solid #e7edf6;
}

.page-hero h1 {
    margin: 14px 0 14px;
    font-size: clamp(2rem, 9vw, 3.6rem);
    line-height: 1.12;
    letter-spacing: -0.04em;
    color: #16233b;
}

.page-hero p {
    max-width: 780px;
    color: #607086;
    font-size: 1.04rem;
}

.article-layout {
    display: grid;
    gap: 24px;
    align-items: start;
}

.article-content {
    background: #ffffff;
    border: 1px solid #e5ebf5;
    border-radius: 28px;
    padding: 24px;
    box-shadow: 0 16px 38px rgba(28,45,80,.05);
}

.article-content h2 {
    margin-top: 24px;
    color: #16233b;
}

.article-content p {
    color: #596a80;
}

.article-highlight {
    margin: 24px 0;
    padding: 18px;
    border-radius: 22px;
    background: #f3f7ff;
    border: 1px solid #dfeaff;
    color: #40536d;
}

.sidebar-stack {
    display: grid;
    gap: 16px;
}

.download-panel {
    text-align: center;
    background: #ffffff;
    border: 1px solid #e5ebf5;
    border-radius: 28px;
    padding: 26px;
    box-shadow: 0 18px 42px rgba(27, 43, 78, 0.06);
}

.download-steps {
    display: grid;
    gap: 16px;
    margin-top: 24px;
}

.download-step {
    display: flex;
    gap: 14px;
    align-items: flex-start;
    padding: 16px;
    border: 1px solid #e4ebf6;
    border-radius: 20px;
    background: #fff;
}

.download-step span {
    flex: 0 0 34px;
    width: 34px;
    height: 34px;
    display: grid;
    place-items: center;
    border-radius: 50%;
    color: #fff;
    background: #2980fe;
    font-weight: 850;
}

.site-footer {
    background: #111d33;
    color: rgba(255,255,255,0.78);
    padding: 46px 0 0;
}

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

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

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

.site-footer a {
    display: block;
    color: rgba(255,255,255,0.76);
    padding: 4px 0;
}

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

.footer-bottom {
    margin-top: 34px;
    padding: 18px 16px;
    text-align: center;
    border-top: 1px solid rgba(255,255,255,.12);
    color: rgba(255,255,255,0.65);
}

@media (min-width: 680px) {
    .node-grid,
    .card-grid,
    .risk-grid,
    .faq-grid,
    .policy-grid,
    .device-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

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

@media (min-width: 960px) {
    .nav-toggle-label {
        display: none;
    }

    .site-nav {
        position: static;
        display: flex;
        align-items: center;
        gap: 4px;
        padding: 0;
        border: 0;
        box-shadow: none;
        background: transparent;
    }

    .site-nav a {
        padding: 8px 11px;
        font-size: 0.94rem;
    }

    .hero-inner {
        grid-template-columns: 1.08fr 0.92fr;
        padding: 86px 0 72px;
    }

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

    .split-section,
    .article-layout {
        grid-template-columns: minmax(0, 1.05fr) minmax(310px, 0.65fr);
    }

    .split-section.reverse {
        grid-template-columns: minmax(310px, 0.78fr) minmax(0, 1fr);
    }

    .split-section.reverse .section-copy {
        order: 2;
    }

    .split-section.reverse .visual-panel,
    .split-section.reverse .map-panel,
    .split-section.reverse .privacy-panel,
    .split-section.reverse .protocol-panel {
        order: 1;
    }

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

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

    .section {
        padding: 76px 0;
    }

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

@media (max-width: 420px) {
    .container,
    .hero-inner,
    .header-inner {
        width: min(100% - 24px, 1180px);
    }

    .download-btn {
        width: 100%;
    }

    .status-card {
        position: static;
        margin: 8px;
        width: fit-content;
    }

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

    .floating-tags {
        margin-top: 12px;
    }
}