:root {
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #1f2937;
    --muted: #667085;
    --light: #f5f7fb;
    --line: #e5eaf2;
    --card: #ffffff;
    --shadow: 0 18px 48px rgba(35, 55, 120, 0.10);
    --radius: 28px;
}

* {
    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: 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;
    line-height: 1.22;
    color: #111827;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(18px);
    border-bottom: 1px solid rgba(229,234,242,0.86);
}

.header-inner {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.logo,
.footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #13213c;
    letter-spacing: -0.02em;
}

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

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

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

.nav-toggle-label span {
    width: 18px;
    height: 2px;
    border-radius: 999px;
    background: #1f2937;
}

.site-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    display: none;
    flex-direction: column;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: #fff;
    box-shadow: var(--shadow);
}

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

.site-nav a {
    padding: 11px 12px;
    border-radius: 12px;
    color: #344054;
    font-weight: 650;
    font-size: 15px;
}

.site-nav a:hover,
.site-nav a.active {
    color: var(--blue);
    background: #eef5ff;
}

.container,
.section-inner {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
}

.section {
    padding: 64px 0;
}

.section-muted {
    background: linear-gradient(180deg, #f7f9ff 0%, #ffffff 100%);
}

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

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

.section-title .eyebrow,
.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    padding: 6px 12px;
    border-radius: 999px;
    background: #eef5ff;
    color: var(--blue);
    font-size: 13px;
    font-weight: 800;
}

.section-title h2 {
    font-size: clamp(28px, 4vw, 44px);
    letter-spacing: -0.04em;
    margin-bottom: 12px;
}

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

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: var(--blue);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 30px rgba(41,128,254,0.25);
    transition: background .2s ease, transform .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    background: var(--blue-dark);
    transform: translateY(-2px);
    box-shadow: 0 18px 36px rgba(23,104,232,0.28);
}

.vpn-saas-hero {
    position: relative;
    padding: 42px 0 72px;
    color: #fff;
    overflow: hidden;
    background: var(--gradient);
}

.vpn-saas-hero::after {
    content: "";
    position: absolute;
    left: -10%;
    right: -10%;
    bottom: -90px;
    height: 160px;
    background: #fff;
    transform: rotate(-3deg);
    transform-origin: left top;
}

.hero-inner {
    position: relative;
    z-index: 2;
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    display: grid;
    gap: 34px;
    align-items: center;
}

.hero-copy h1 {
    color: #fff;
    font-size: clamp(36px, 7vw, 68px);
    letter-spacing: -0.06em;
    margin-bottom: 18px;
}

.hero-copy p {
    max-width: 650px;
    color: rgba(255,255,255,0.88);
    font-size: 18px;
}

.hero-actions {
    display: flex;
    align-items: center;
    gap: 14px;
    flex-wrap: wrap;
    margin: 28px 0 18px;
}

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

.hero-tags span,
.floating-tags span {
    display: inline-flex;
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,0.16);
    color: #fff;
    border: 1px solid rgba(255,255,255,0.24);
    font-size: 13px;
    font-weight: 700;
}

.hero-device {
    position: relative;
    min-height: 360px;
}

.hero-device-card {
    position: relative;
    margin: 0 auto;
    padding: 22px;
    max-width: 420px;
    border-radius: 36px;
    background: rgba(255,255,255,0.18);
    border: 1px solid rgba(255,255,255,0.28);
    box-shadow: 0 28px 80px rgba(0,0,0,0.18);
}

.hero-device-card img {
    border-radius: 28px;
    background: #fff;
}

.status-card {
    position: absolute;
    z-index: 2;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 13px;
    border-radius: 18px;
    background: #fff;
    color: #1d2939;
    box-shadow: var(--shadow);
    font-weight: 800;
    font-size: 13px;
}

.status-card::before {
    content: "";
    width: 9px;
    height: 9px;
    border-radius: 999px;
    background: var(--blue);
}

.status-one { top: 14px; left: 6px; }
.status-two { top: 42%; right: -4px; }
.status-three { bottom: 52px; left: -2px; }
.status-four { bottom: 6px; right: 36px; }

.product-highlights {
    position: relative;
    z-index: 4;
    margin-top: -34px;
    padding-bottom: 44px;
}

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

.highlight-card,
.feature-card,
.risk-card,
.faq-card,
.step-card,
.info-card,
.sidebar-card,
.timeline-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 24px;
    box-shadow: 0 14px 34px rgba(30, 48, 88, 0.06);
}

.highlight-card {
    padding: 22px;
}

.highlight-card .tag {
    display: inline-flex;
    margin-bottom: 12px;
    padding: 5px 10px;
    border-radius: 999px;
    background: #eef5ff;
    color: var(--blue);
    font-size: 12px;
    font-weight: 800;
}

.highlight-card h3 {
    font-size: 19px;
    margin-bottom: 8px;
}

.highlight-card p,
.feature-card p,
.risk-card p,
.step-card p,
.info-card p,
.sidebar-card p {
    color: var(--muted);
}

.text-link {
    display: inline-flex;
    margin-top: 8px;
    color: var(--blue);
    font-weight: 800;
}

.feature-split,
.image-split,
.speed-layout,
.nodes-layout,
.device-layout,
.protocol-layout,
.download-layout,
.about-grid,
.article-layout {
    display: grid;
    gap: 26px;
    align-items: center;
}

.feature-panel {
    padding: 28px;
    border-radius: 32px;
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.feature-panel h2 {
    margin-bottom: 14px;
    font-size: clamp(26px, 4vw, 42px);
}

.feature-panel p {
    color: var(--muted);
}

.feature-list {
    display: grid;
    gap: 10px;
    margin: 18px 0 8px;
    padding: 0;
    list-style: none;
}

.feature-list li {
    position: relative;
    padding: 12px 14px 12px 38px;
    border-radius: 16px;
    background: #f6f9ff;
    color: #344054;
    font-weight: 650;
}

.feature-list li::before {
    content: "";
    position: absolute;
    left: 16px;
    top: 19px;
    width: 9px;
    height: 9px;
    border-radius: 99px;
    background: var(--blue);
}

.image-card,
.visual-card {
    padding: 18px;
    border-radius: 34px;
    background: linear-gradient(180deg, #ffffff, #f4f7ff);
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.image-card img,
.visual-card img {
    border-radius: 26px;
}

.high-speed-section {
    background: #f7f9fd;
}

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

.metric-card {
    padding: 22px;
    border-radius: 26px;
    background: #fff;
    border: 1px solid var(--line);
}

.metric-card strong {
    display: block;
    color: #111827;
    font-size: 21px;
    margin-bottom: 6px;
}

.global-nodes-section .node-list {
    display: grid;
    gap: 12px;
}

.node-item {
    padding: 16px;
    border-left: 4px solid var(--blue);
    border-radius: 18px;
    background: #fff;
    border-top: 1px solid var(--line);
    border-right: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.privacy-protection-section {
    background: linear-gradient(180deg, #fff 0%, #f7f9ff 100%);
}

.privacy-board {
    display: grid;
    gap: 18px;
}

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

.privacy-card {
    padding: 20px;
    border-radius: 24px;
    background: #fff;
    border: 1px solid var(--line);
}

.privacy-card h3 {
    margin-bottom: 8px;
}

.no-log-policy-section .policy-strip {
    display: grid;
    gap: 14px;
}

.policy-item {
    padding: 20px;
    border-radius: 24px;
    background: #fff;
    border: 1px solid var(--line);
}

.multi-device-section {
    background: #f8fafc;
}

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

.device-pill {
    padding: 16px 18px;
    border-radius: 20px;
    background: #fff;
    border: 1px solid var(--line);
    font-weight: 800;
}

.encryption-protocol-section .tech-panel {
    padding: 24px;
    border-radius: 32px;
    color: #fff;
    background: var(--gradient);
}

.tech-panel h2 {
    color: #fff;
    margin-bottom: 12px;
}

.tech-panel p {
    color: rgba(255,255,255,0.88);
}

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

.protocol-card {
    padding: 18px;
    border-radius: 22px;
    background: rgba(255,255,255,0.14);
    border: 1px solid rgba(255,255,255,0.22);
}

.protocol-card h3 {
    color: #fff;
    margin-bottom: 6px;
}

.process-steps {
    display: grid;
    gap: 14px;
}

.step-card {
    padding: 20px;
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border-radius: 15px;
    background: #eef5ff;
    color: var(--blue);
    font-weight: 900;
    margin-bottom: 12px;
}

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

.risk-card {
    padding: 20px;
    border-top: 4px solid var(--blue);
}

.risk-card h3 {
    margin-bottom: 8px;
}

.risk-card strong {
    color: #111827;
}

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

.faq-card {
    padding: 20px;
}

.faq-card h3 {
    margin-bottom: 8px;
    font-size: 18px;
}

.cta-section {
    padding: 76px 0;
}

.cta-box {
    width: min(980px, calc(100% - 32px));
    margin: 0 auto;
    padding: 38px 24px;
    border-radius: 36px;
    text-align: center;
    color: #fff;
    background: var(--gradient);
    box-shadow: 0 24px 70px rgba(72, 81, 219, 0.24);
}

.cta-box h2 {
    color: #fff;
    font-size: clamp(28px, 5vw, 46px);
    margin-bottom: 12px;
}

.cta-box p {
    color: rgba(255,255,255,0.88);
    max-width: 690px;
    margin: 0 auto 24px;
}

.page-hero {
    padding: 56px 0 34px;
    background: linear-gradient(180deg, #f5f8ff 0%, #fff 100%);
}

.page-hero-inner {
    width: min(920px, calc(100% - 32px));
    margin: 0 auto;
}

.page-hero h1 {
    font-size: clamp(32px, 6vw, 54px);
    letter-spacing: -0.05em;
    margin-bottom: 14px;
}

.page-hero p {
    color: var(--muted);
    font-size: 18px;
}

.article-layout {
    align-items: start;
    padding: 28px 0 72px;
}

.article-main {
    display: grid;
    gap: 18px;
}

.content-card {
    padding: 24px;
    border-radius: 28px;
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: 0 14px 34px rgba(30,48,88,0.05);
}

.content-card h2 {
    font-size: 26px;
    margin-bottom: 12px;
}

.content-card h3 {
    font-size: 20px;
    margin-bottom: 8px;
}

.content-card p,
.content-card li {
    color: var(--muted);
}

.check-list,
.number-list {
    margin: 0;
    padding-left: 20px;
    color: var(--muted);
}

.check-list li,
.number-list li {
    margin-bottom: 10px;
}

.sidebar {
    display: grid;
    gap: 14px;
}

.sidebar-card {
    padding: 20px;
}

.sidebar-card h3 {
    margin-bottom: 10px;
}

.related-links {
    display: grid;
    gap: 9px;
}

.related-links a {
    padding: 10px 12px;
    border-radius: 14px;
    background: #f5f8ff;
    color: var(--blue);
    font-weight: 750;
}

.download-page-card {
    padding: 28px;
    border-radius: 32px;
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.download-page-card h2 {
    margin-bottom: 14px;
}

.download-steps {
    counter-reset: step;
    display: grid;
    gap: 14px;
    margin: 24px 0;
}

.download-step {
    position: relative;
    padding: 18px 18px 18px 64px;
    border-radius: 20px;
    background: #f7f9ff;
    border: 1px solid var(--line);
}

.download-step::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 18px;
    top: 18px;
    width: 32px;
    height: 32px;
    border-radius: 12px;
    background: var(--blue);
    color: #fff;
    font-weight: 900;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.download-action {
    margin: 22px 0;
    text-align: center;
}

.about-feature {
    padding: 24px;
    border-radius: 28px;
    background: #fff;
    border: 1px solid var(--line);
}

.site-footer {
    background: #101828;
    color: #d0d5dd;
    padding: 48px 0 0;
}

.footer-inner {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    display: grid;
    gap: 28px;
}

.footer-logo {
    color: #fff;
    margin-bottom: 14px;
}

.footer-brand p {
    max-width: 440px;
    color: #98a2b3;
}

.footer-links {
    display: grid;
    gap: 18px;
}

.footer-links h3 {
    color: #fff;
    font-size: 16px;
    margin-bottom: 10px;
}

.footer-links a {
    display: block;
    color: #98a2b3;
    margin: 8px 0;
}

.footer-links a:hover {
    color: #fff;
}

.footer-bottom {
    margin-top: 34px;
    padding: 18px 0;
    border-top: 1px solid rgba(255,255,255,0.08);
    text-align: center;
    color: #98a2b3;
}

@media (min-width: 640px) {
    .highlights-grid,
    .privacy-cards,
    .policy-strip,
    .speed-metrics,
    .process-steps,
    .risk-grid,
    .faq-grid,
    .footer-links {
        grid-template-columns: repeat(2, 1fr);
    }

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

@media (min-width: 900px) {
    .nav-toggle-label {
        display: none;
    }

    .site-nav {
        position: static;
        display: flex;
        flex-direction: row;
        align-items: center;
        padding: 0;
        border: 0;
        box-shadow: none;
        background: transparent;
        gap: 2px;
    }

    .site-nav a {
        font-size: 14px;
        padding: 9px 10px;
    }

    .hero-inner {
        grid-template-columns: 1.05fr 0.95fr;
    }

    .feature-split,
    .image-split,
    .speed-layout,
    .nodes-layout,
    .device-layout,
    .protocol-layout,
    .download-layout,
    .about-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .privacy-board {
        grid-template-columns: 1.05fr 0.95fr;
        align-items: center;
    }

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

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

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

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

    .faq-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-inner {
        grid-template-columns: 1.1fr 1.4fr;
    }

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

@media (min-width: 1120px) {
    .site-nav a {
        font-size: 15px;
        padding: 9px 12px;
    }

    .section {
        padding: 82px 0;
    }

    .process-steps {
        grid-template-columns: repeat(6, 1fr);
    }
}

@media (max-width: 480px) {
    .header-inner,
    .container,
    .section-inner,
    .hero-inner,
    .page-hero-inner {
        width: min(100% - 24px, 1180px);
    }

    .vpn-saas-hero {
        padding-top: 32px;
    }

    .hero-actions {
        align-items: stretch;
    }

    .download-btn {
        width: 100%;
        min-height: 52px;
    }

    .status-card {
        position: static;
        margin: 8px 6px 0 0;
    }

    .hero-device {
        min-height: auto;
    }

    .hero-device-card {
        padding: 14px;
    }

    .feature-panel,
    .content-card,
    .download-page-card {
        padding: 20px;
    }

    .section {
        padding: 54px 0;
    }

    .cta-box {
        border-radius: 28px;
    }
}