/* 移动端优先的响应式样式 */
:root {
    --primary: #2980FE;
    --primary-hover: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #202A3A;
    --muted: #667085;
    --light: #F5F7FB;
    --soft: #EEF4FF;
    --line: #E4E8F0;
    --card: #FFFFFF;
    --radius: 24px;
    --shadow: 0 18px 42px rgba(30, 49, 92, 0.10);
}

* {
    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: var(--text);
    background: #FFFFFF;
    line-height: 1.72;
    overflow-x: hidden;
}

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

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

p {
    margin: 0 0 14px;
}

h1, h2, h3 {
    margin: 0 0 14px;
    line-height: 1.22;
}

h1 {
    font-size: clamp(34px, 8vw, 64px);
    letter-spacing: -1.5px;
}

h2 {
    font-size: clamp(26px, 4.8vw, 42px);
    letter-spacing: -0.8px;
}

h3 {
    font-size: 20px;
}

.container {
    width: min(1120px, calc(100% - 36px));
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.94);
    backdrop-filter: blur(18px);
    border-bottom: 1px solid rgba(228, 232, 240, 0.85);
}

.header-inner {
    width: min(1180px, calc(100% - 28px));
    margin: 0 auto;
    min-height: 70px;
    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: #18233A;
}

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

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

.nav-toggle span {
    width: 19px;
    height: 2px;
    background: #24324B;
    border-radius: 8px;
}

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

.site-nav.is-open {
    display: grid;
    gap: 8px;
}

.site-nav a {
    padding: 11px 12px;
    border-radius: 14px;
    color: #4A5873;
    font-size: 15px;
    font-weight: 650;
}

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

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #FFFFFF;
    font-weight: 800;
    letter-spacing: 0.2px;
    border: 0;
    box-shadow: 0 12px 26px rgba(41, 128, 254, 0.26);
    transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.download-btn:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 16px 30px rgba(23, 104, 232, 0.28);
}

.section {
    padding: 72px 0;
}

.section-soft {
    background: linear-gradient(180deg, #F8FAFF 0%, #FFFFFF 100%);
}

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

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

.section-title p {
    color: var(--muted);
    font-size: 17px;
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    border-radius: 999px;
    background: #EAF2FF;
    color: var(--primary);
    font-weight: 800;
    font-size: 14px;
    margin-bottom: 16px;
}

.text-link {
    color: var(--primary);
    font-weight: 800;
}

.text-link:hover {
    color: var(--primary-hover);
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #FFFFFF;
    background: var(--gradient);
    padding: 76px 0 52px;
}

.vpn-network-hero::before,
.cta-section::before,
.global-nodes-section::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle at 20% 25%, rgba(255,255,255,0.24) 0 2px, transparent 3px),
        radial-gradient(circle at 65% 35%, rgba(255,255,255,0.20) 0 2px, transparent 3px),
        radial-gradient(circle at 80% 68%, rgba(255,255,255,0.18) 0 2px, transparent 3px),
        linear-gradient(120deg, transparent 0%, rgba(255,255,255,0.13) 48%, transparent 49%),
        linear-gradient(30deg, transparent 0%, rgba(255,255,255,0.10) 35%, transparent 36%);
    opacity: 0.95;
    pointer-events: none;
}

.hero-grid {
    position: relative;
    z-index: 1;
    display: grid;
    gap: 36px;
    align-items: center;
}

.hero-copy p {
    font-size: 17px;
    color: rgba(255,255,255,0.86);
    max-width: 640px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    margin: 26px 0 20px;
}

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

.security-tags span,
.hero-status-row span {
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,0.16);
    border: 1px solid rgba(255,255,255,0.22);
    color: rgba(255,255,255,0.92);
    font-weight: 700;
    font-size: 14px;
}

.hero-visual {
    position: relative;
    min-height: 330px;
}

.hero-device {
    position: relative;
    z-index: 2;
    width: min(470px, 92%);
    margin: 0 auto;
    border-radius: 32px;
    padding: 18px;
    background: rgba(255,255,255,0.16);
    border: 1px solid rgba(255,255,255,0.28);
    box-shadow: 0 30px 80px rgba(14, 20, 60, 0.26);
    backdrop-filter: blur(14px);
}

.hero-device img {
    border-radius: 24px;
}

.float-card {
    position: absolute;
    z-index: 3;
    padding: 10px 14px;
    border-radius: 16px;
    background: rgba(255,255,255,0.92);
    color: #1A2A44;
    font-weight: 800;
    font-size: 14px;
    box-shadow: 0 14px 30px rgba(14, 24, 62, 0.16);
}

.float-card.one { top: 12px; left: 6px; }
.float-card.two { top: 78px; right: 0; }
.float-card.three { bottom: 80px; left: 0; }
.float-card.four { bottom: 18px; right: 16px; }

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

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

.node-card,
.info-card,
.risk-card,
.faq-item,
.policy-card,
.step-card,
.device-card,
.protocol-card,
.tip-box {
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: 0 12px 32px rgba(27, 47, 94, 0.06);
}

.node-card {
    padding: 22px;
}

.node-label {
    display: inline-flex;
    padding: 5px 10px;
    border-radius: 999px;
    background: #EAF2FF;
    color: var(--primary);
    font-size: 13px;
    font-weight: 900;
    margin-bottom: 12px;
}

.node-card p,
.info-card p,
.policy-card p,
.step-card p,
.risk-card p,
.faq-item p,
.protocol-card p,
.tip-box p {
    color: var(--muted);
}

.split-section,
.vpn-connection-section,
.high-speed-section,
.privacy-protection-section,
.multi-device-section,
.encryption-protocol-section {
    display: grid;
    gap: 30px;
    align-items: center;
}

.split-visual {
    position: relative;
    border-radius: 32px;
    overflow: hidden;
    background: #F1F5FF;
    padding: 18px;
    box-shadow: var(--shadow);
}

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

.feature-list {
    display: grid;
    gap: 12px;
    margin: 20px 0 22px;
}

.feature-list li,
.check-list li,
.simple-list li {
    list-style: none;
    position: relative;
    padding-left: 28px;
    color: #43506A;
}

.feature-list li::before,
.check-list li::before,
.simple-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 10px;
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--primary);
    box-shadow: 0 0 0 5px rgba(41,128,254,0.12);
}

.global-nodes-section {
    position: relative;
    overflow: hidden;
    border-radius: 34px;
    padding: 34px;
    color: #FFFFFF;
    background: var(--gradient);
}

.global-nodes-section .section-title p {
    color: rgba(255,255,255,0.82);
}

.map-grid {
    position: relative;
    z-index: 1;
    display: grid;
    gap: 22px;
    align-items: center;
}

.node-panel {
    display: grid;
    gap: 12px;
}

.node-panel .info-card {
    padding: 18px;
    background: rgba(255,255,255,0.92);
    color: #1F2A44;
}

.node-panel .info-card p {
    color: #5F6C82;
}

.speed-lines {
    display: grid;
    gap: 14px;
    margin: 20px 0;
}

.speed-line {
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 16px;
}

.speed-line strong {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    color: #202A3A;
}

.bar {
    height: 8px;
    margin-top: 12px;
    border-radius: 999px;
    background: #EAF1FF;
    overflow: hidden;
}

.bar span {
    display: block;
    height: 100%;
    border-radius: inherit;
    background: var(--primary);
}

.privacy-panel {
    padding: 24px;
    border-radius: 30px;
    background: #FFFFFF;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.privacy-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 16px;
}

.privacy-tags span {
    border-radius: 999px;
    padding: 8px 12px;
    background: #F1F6FF;
    color: #295BBD;
    font-weight: 800;
    font-size: 14px;
}

.no-log-policy-section {
    display: grid;
    gap: 18px;
}

.policy-card,
.protocol-card,
.device-card,
.step-card,
.risk-card,
.info-card,
.tip-box {
    padding: 22px;
}

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

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

.step-card {
    position: relative;
    padding-left: 78px;
}

.step-number {
    position: absolute;
    left: 22px;
    top: 22px;
    width: 38px;
    height: 38px;
    border-radius: 14px;
    display: grid;
    place-items: center;
    background: var(--primary);
    color: #FFFFFF;
    font-weight: 900;
}

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

.risk-card em {
    display: block;
    margin-top: 10px;
    color: #33415F;
    font-style: normal;
    font-weight: 800;
}

.faq-list {
    display: grid;
    gap: 14px;
}

.faq-item {
    padding: 20px;
}

.cta-section {
    position: relative;
    overflow: hidden;
    border-radius: 34px;
    background: var(--gradient);
    color: #FFFFFF;
    padding: 46px 26px;
    text-align: center;
}

.cta-section > * {
    position: relative;
    z-index: 1;
}

.cta-section p {
    color: rgba(255,255,255,0.84);
    max-width: 720px;
    margin: 0 auto 24px;
}

.page-hero {
    padding: 56px 0 34px;
    background: linear-gradient(180deg, #F7FAFF 0%, #FFFFFF 100%);
}

.page-hero .container {
    max-width: 980px;
}

.page-hero p {
    max-width: 760px;
    color: var(--muted);
    font-size: 17px;
}

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

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

.article-card {
    padding: 24px;
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: 28px;
    box-shadow: 0 12px 32px rgba(27, 47, 94, 0.05);
}

.article-card p,
.article-card li {
    color: #536074;
}

.article-card ul,
.article-card ol,
.feature-list,
.check-list,
.simple-list {
    margin: 0;
    padding: 0;
}

.article-card li {
    margin-bottom: 10px;
}

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

.side-panel .tip-box {
    background: #F8FAFF;
}

.download-panel {
    text-align: center;
    padding: 34px 22px;
    border-radius: 30px;
    background: linear-gradient(180deg, #F8FBFF 0%, #FFFFFF 100%);
    border: 1px solid var(--line);
}

.download-steps {
    display: grid;
    gap: 14px;
    margin-top: 24px;
}

.download-step {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: #FFFFFF;
}

.site-footer {
    margin-top: 72px;
    padding: 52px 0 0;
    background: #172033;
    color: rgba(255,255,255,0.76);
}

.site-footer a {
    display: block;
    color: rgba(255,255,255,0.76);
    margin: 8px 0;
}

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

.footer-grid {
    display: grid;
    gap: 28px;
}

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

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

.footer-bottom {
    margin-top: 34px;
    padding: 18px;
    border-top: 1px solid rgba(255,255,255,0.12);
    text-align: center;
}

.footer-bottom p {
    margin: 0;
    color: rgba(255,255,255,0.62);
}

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

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

    .footer-grid {
        grid-template-columns: 1.3fr repeat(3, 1fr);
    }
}

@media (min-width: 960px) {
    .nav-toggle {
        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 10px;
    }

    .vpn-network-hero {
        padding: 96px 0 74px;
    }

    .hero-grid,
    .split-section,
    .vpn-connection-section,
    .high-speed-section,
    .privacy-protection-section,
    .multi-device-section,
    .encryption-protocol-section,
    .map-grid,
    .article-layout {
        grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    }

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

    .side-panel {
        position: sticky;
        top: 96px;
    }

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

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

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

    .container {
        width: min(1120px, calc(100% - 48px));
    }

    .section {
        padding: 92px 0;
    }
}

@media (min-width: 1180px) {
    .site-nav a {
        padding: 9px 13px;
    }
}