* {
    box-sizing: border-box;
}

:root {
    --brand-gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #1f2937;
    --muted: #667085;
    --soft: #f5f7fb;
    --soft-blue: #f2f6ff;
    --border: #e6eaf2;
    --white: #ffffff;
    --card-shadow: 0 18px 50px rgba(39, 64, 125, 0.10);
}

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: 1.7;
    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, 0.92);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(230, 234, 242, 0.88);
}

.nav-shell {
    width: min(1180px, calc(100% - 24px));
    margin: 0 auto;
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.logo,
.brand,
.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #111827;
    letter-spacing: -0.02em;
}

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

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

.nav-toggle {
    width: 44px;
    height: 44px;
    border: 1px solid var(--border);
    border-radius: 14px;
    display: grid;
    place-content: center;
    gap: 5px;
    cursor: pointer;
    background: #fff;
}

.nav-toggle span {
    width: 20px;
    height: 2px;
    background: #1f2937;
    border-radius: 999px;
    display: block;
}

.site-nav {
    position: absolute;
    left: 12px;
    right: 12px;
    top: 76px;
    display: none;
    flex-direction: column;
    padding: 14px;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 22px;
    box-shadow: var(--card-shadow);
}

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

.site-nav a {
    padding: 12px 14px;
    border-radius: 14px;
    color: #475467;
    font-size: 15px;
    font-weight: 650;
}

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

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 26px;
    border-radius: 999px;
    background: var(--blue);
    color: #fff;
    font-weight: 760;
    box-shadow: 0 14px 26px rgba(41, 128, 254, 0.24);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
    border: 0;
    cursor: pointer;
}

.download-btn:hover {
    background: var(--blue-dark);
    transform: translateY(-2px);
    box-shadow: 0 18px 32px rgba(23, 104, 232, 0.28);
}

.vpn-saas-hero {
    position: relative;
    overflow: hidden;
    background: var(--brand-gradient);
    color: #fff;
    border-bottom-left-radius: 34px;
    border-bottom-right-radius: 34px;
}

.vpn-saas-hero::after {
    content: "";
    position: absolute;
    left: -10%;
    right: -10%;
    bottom: -80px;
    height: 150px;
    background: #fff;
    transform: rotate(-3deg);
    transform-origin: left top;
}

.hero-grid {
    position: relative;
    z-index: 2;
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    padding: 72px 0 86px;
    display: grid;
    gap: 34px;
    align-items: center;
}

.eyebrow,
.category-badge {
    display: inline-flex;
    width: fit-content;
    align-items: center;
    gap: 8px;
    padding: 7px 12px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 760;
    color: var(--blue);
    background: #eef5ff;
}

.hero-eyebrow {
    color: #fff;
    background: rgba(255, 255, 255, 0.16);
    border: 1px solid rgba(255, 255, 255, 0.25);
}

.hero-copy h1 {
    margin: 18px 0 18px;
    font-size: clamp(34px, 9vw, 66px);
    line-height: 1.06;
    letter-spacing: -0.06em;
}

.hero-copy p {
    margin: 0 0 26px;
    color: rgba(255, 255, 255, 0.88);
    font-size: 17px;
}

.hero-tags,
.tag-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 20px;
}

.hero-tags span,
.tag-row span {
    display: inline-flex;
    padding: 7px 12px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.15);
    color: rgba(255, 255, 255, 0.92);
    border: 1px solid rgba(255, 255, 255, 0.25);
    font-size: 13px;
    font-weight: 650;
}

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

.product-shell {
    width: min(430px, 92%);
    padding: 20px;
    border-radius: 36px;
    background: rgba(255, 255, 255, 0.17);
    box-shadow: 0 32px 80px rgba(0, 0, 0, 0.18);
    border: 1px solid rgba(255, 255, 255, 0.28);
    backdrop-filter: blur(12px);
}

.product-shell img {
    width: 100%;
    border-radius: 28px;
    background: #fff;
}

.float-card {
    position: absolute;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 14px;
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.94);
    color: #1f2937;
    box-shadow: 0 18px 44px rgba(0, 0, 0, 0.16);
    font-size: 14px;
    font-weight: 760;
}

.float-card::before {
    content: "";
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--blue);
}

.float-card.card-a { top: 24px; left: 0; }
.float-card.card-b { top: 86px; right: 0; }
.float-card.card-c { bottom: 82px; left: 6px; }
.float-card.card-d { bottom: 26px; right: 18px; }

.section {
    padding: 66px 0;
}

.section-soft {
    background: var(--soft);
}

.section-head {
    margin-bottom: 28px;
    max-width: 780px;
}

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

.section-head h2 {
    margin: 12px 0 10px;
    font-size: clamp(28px, 5vw, 44px);
    line-height: 1.15;
    letter-spacing: -0.04em;
}

.section-head p,
.lead,
.page-summary {
    color: var(--muted);
    font-size: 16px;
    margin: 0;
}

.product-highlights {
    position: relative;
    z-index: 3;
    margin-top: -36px;
}

.highlight-grid,
.card-grid,
.risk-grid,
.faq-grid,
.related-grid,
.feature-list,
.info-grid {
    display: grid;
    gap: 18px;
}

.highlight-card,
.info-card,
.risk-card,
.faq-item,
.step-card,
.related-card,
.side-panel,
.tip-box,
.check-card,
.pillar-card,
.feature-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 26px;
    box-shadow: 0 14px 40px rgba(20, 31, 56, 0.06);
}

.highlight-card,
.info-card,
.risk-card,
.faq-item,
.step-card,
.related-card,
.check-card,
.pillar-card,
.feature-card {
    padding: 22px;
}

.highlight-card .mini-label,
.info-card .mini-label,
.risk-card .mini-label {
    display: inline-flex;
    padding: 5px 9px;
    border-radius: 999px;
    background: var(--soft-blue);
    color: var(--blue);
    font-size: 12px;
    font-weight: 800;
}

.highlight-card h3,
.info-card h3,
.risk-card h3,
.faq-item h3,
.step-card h3,
.pillar-card h3,
.feature-card h3 {
    margin: 12px 0 8px;
    font-size: 19px;
    line-height: 1.35;
}

.highlight-card p,
.info-card p,
.risk-card p,
.faq-item p,
.step-card p,
.related-card p,
.check-card p,
.pillar-card p,
.feature-card p,
.side-panel p {
    margin: 0;
    color: var(--muted);
    font-size: 15px;
}

.text-link {
    display: inline-flex;
    margin-top: 14px;
    color: var(--blue);
    font-weight: 760;
}

.vpn-connection-section,
.high-speed-section,
.global-nodes-section,
.multi-device-section,
.encryption-protocol-section,
.feature-split {
    display: grid;
    gap: 26px;
    align-items: center;
}

.panel {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 34px;
    padding: 28px;
    box-shadow: var(--card-shadow);
}

.panel h2 {
    margin: 12px 0 14px;
    font-size: clamp(28px, 5vw, 42px);
    line-height: 1.16;
    letter-spacing: -0.04em;
}

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

.panel ul,
.check-list,
.clean-list {
    padding: 0;
    margin: 18px 0 0;
    list-style: none;
    display: grid;
    gap: 10px;
}

.panel li,
.check-list li,
.clean-list li {
    position: relative;
    padding-left: 26px;
    color: #3b4758;
}

.panel li::before,
.check-list li::before,
.clean-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 12px;
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--blue);
}

.image-card {
    border-radius: 34px;
    padding: 18px;
    background: linear-gradient(180deg, #ffffff, #f1f5ff);
    border: 1px solid var(--border);
    box-shadow: var(--card-shadow);
}

.image-card img {
    border-radius: 26px;
    width: 100%;
    object-fit: cover;
}

.speed-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 34px;
    padding: 24px;
    box-shadow: var(--card-shadow);
}

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

.speed-lines div {
    padding: 14px;
    border-radius: 18px;
    background: #f6f8fc;
}

.global-lines {
    display: grid;
    gap: 14px;
}

.global-lines .line {
    padding: 16px;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 20px;
}

.privacy-protection-section {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 36px;
    padding: 24px;
    box-shadow: var(--card-shadow);
    display: grid;
    gap: 22px;
}

.privacy-cards,
.no-log-policy-section,
.protocol-grid {
    display: grid;
    gap: 16px;
}

.no-log-policy-section {
    grid-template-columns: 1fr;
}

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

.device-tile {
    padding: 18px;
    border-radius: 24px;
    background: #fff;
    border: 1px solid var(--border);
}

.encryption-protocol-section {
    background: #111827;
    color: #fff;
    border-radius: 36px;
    padding: 26px;
    overflow: hidden;
}

.encryption-protocol-section p,
.encryption-protocol-section li {
    color: rgba(255, 255, 255, 0.72);
}

.encryption-protocol-section .text-link {
    color: #9bc4ff;
}

.protocol-grid .info-card {
    background: rgba(255,255,255,0.08);
    border-color: rgba(255,255,255,0.12);
    box-shadow: none;
}

.protocol-grid .info-card p,
.protocol-grid .info-card h3 {
    color: #fff;
}

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

.step-card {
    position: relative;
    padding-top: 54px;
}

.step-card::before {
    counter-increment: steps;
    content: counter(steps, decimal-leading-zero);
    position: absolute;
    top: 18px;
    left: 22px;
    color: var(--blue);
    font-weight: 900;
    font-size: 18px;
}

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

.risk-card strong {
    display: block;
    color: #1f2937;
    margin-bottom: 6px;
}

.faq-item {
    box-shadow: none;
}

.cta-section {
    margin: 56px auto 0;
    width: min(1120px, calc(100% - 32px));
    border-radius: 36px;
    padding: 42px 24px;
    text-align: center;
    color: #fff;
    background: var(--brand-gradient);
    overflow: hidden;
    position: relative;
}

.cta-section h2 {
    margin: 0 0 12px;
    font-size: clamp(28px, 5vw, 42px);
    line-height: 1.15;
}

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

.page-hero {
    padding: 54px 0 36px;
    background: linear-gradient(180deg, #f5f8ff 0%, #ffffff 100%);
}

.page-hero h1 {
    margin: 16px 0 12px;
    font-size: clamp(32px, 7vw, 54px);
    line-height: 1.1;
    letter-spacing: -0.05em;
}

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

.article-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 32px;
    padding: 24px;
    box-shadow: var(--card-shadow);
}

.article-card h2 {
    margin: 8px 0 12px;
    font-size: 26px;
    line-height: 1.25;
}

.article-card p {
    color: var(--muted);
}

.side-panel {
    padding: 22px;
}

.side-panel h2,
.side-panel h3 {
    margin-top: 0;
}

.side-panel a {
    display: block;
    padding: 11px 0;
    color: var(--blue);
    font-weight: 700;
    border-bottom: 1px solid var(--border);
}

.side-panel a:last-child {
    border-bottom: 0;
}

.tip-box {
    padding: 20px;
    background: var(--soft-blue);
    border-color: #dce9ff;
    margin: 22px 0;
}

.tip-box h3 {
    margin: 0 0 8px;
}

.download-panel {
    text-align: center;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 34px;
    padding: 30px;
    box-shadow: var(--card-shadow);
}

.download-panel .download-btn {
    margin-top: 16px;
}

.site-footer {
    margin-top: 72px;
    background: #111827;
    color: #d1d5db;
    padding: 48px 0 0;
}

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

.footer-brand {
    color: #fff;
}

.site-footer p {
    color: #9ca3af;
}

.site-footer h3 {
    color: #fff;
    margin: 0 0 10px;
}

.site-footer a {
    display: block;
    color: #cbd5e1;
    padding: 5px 0;
}

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

.footer-bottom {
    margin-top: 36px;
    border-top: 1px solid rgba(255,255,255,0.10);
    text-align: center;
    padding: 18px;
    color: #9ca3af;
}

@media (min-width: 700px) {
    .highlight-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .card-grid,
    .risk-grid,
    .faq-grid,
    .related-grid,
    .feature-list,
    .info-grid,
    .privacy-cards,
    .protocol-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

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

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

    .site-nav a {
        padding: 8px 10px;
        font-size: 14px;
    }

    .hero-grid {
        grid-template-columns: 1.04fr .96fr;
        padding: 88px 0 110px;
    }

    .hero-copy p {
        font-size: 18px;
        max-width: 650px;
    }

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

    .vpn-connection-section,
    .high-speed-section,
    .global-nodes-section,
    .multi-device-section,
    .feature-split {
        grid-template-columns: 1fr 1fr;
    }

    .privacy-protection-section {
        grid-template-columns: 1.1fr .9fr;
        padding: 34px;
    }

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

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

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

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

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

    .article-card {
        padding: 34px;
    }

    .section {
        padding: 86px 0;
    }
}

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

@media (max-width: 420px) {
    .container {
        width: min(100% - 24px, 1120px);
    }

    .hero-grid {
        width: min(100% - 24px, 1180px);
        padding-top: 52px;
    }

    .float-card {
        position: static;
        margin: 8px 4px 0;
        display: inline-flex;
    }

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

    .product-shell {
        margin: 0 auto 12px;
    }

    .panel,
    .article-card,
    .privacy-protection-section,
    .encryption-protocol-section {
        border-radius: 26px;
        padding: 22px;
    }

    .download-btn {
        width: 100%;
    }
}