* {
    box-sizing: border-box;
}

:root {
    --brand-gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #222B3A;
    --muted: #667085;
    --light: #F5F7FB;
    --line: #E5EAF2;
    --panel: #FFFFFF;
    --soft-blue: #EEF5FF;
    --radius-lg: 32px;
    --radius-md: 24px;
    --shadow: 0 18px 48px rgba(35, 48, 88, 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;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255, 255, 255, 0.94);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(229, 234, 242, 0.86);
}

.header-inner {
    max-width: 1180px;
    margin: 0 auto;
    min-height: 72px;
    padding: 0 18px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 800;
    color: #172033;
}

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

.site-nav {
    display: none;
    flex-direction: column;
    gap: 6px;
    position: absolute;
    top: 72px;
    left: 16px;
    right: 16px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 22px;
    padding: 14px;
    box-shadow: var(--shadow);
}

.site-nav a {
    padding: 10px 12px;
    border-radius: 14px;
    color: #40506B;
    font-size: 15px;
    font-weight: 600;
}

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

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

.nav-toggle-label {
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 14px;
    display: grid;
    place-content: center;
    gap: 5px;
    cursor: pointer;
}

.nav-toggle-label span {
    display: block;
    width: 18px;
    height: 2px;
    background: #263246;
    border-radius: 999px;
}

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

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

.narrow-container {
    width: min(860px, calc(100% - 36px));
    margin: 0 auto;
}

.section {
    padding: 64px 0;
}

.section-title {
    margin: 0 0 16px;
    font-size: clamp(28px, 5vw, 44px);
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.section-lead {
    margin: 0 0 30px;
    color: var(--muted);
    font-size: 17px;
}

.badge {
    display: inline-flex;
    align-items: center;
    min-height: 30px;
    padding: 4px 12px;
    margin-bottom: 16px;
    border-radius: 999px;
    background: var(--soft-blue);
    color: var(--blue);
    font-size: 13px;
    font-weight: 800;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 26px;
    border-radius: 999px;
    background: #2980FE;
    color: #fff;
    font-weight: 800;
    box-shadow: 0 12px 28px rgba(41, 128, 254, 0.26);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    background: #1768E8;
    transform: translateY(-2px);
    box-shadow: 0 16px 32px rgba(23, 104, 232, 0.28);
}

.vpn-saas-hero {
    position: relative;
    overflow: hidden;
    padding: 58px 0 72px;
    background: var(--brand-gradient);
    color: #fff;
    isolation: isolate;
}

.vpn-saas-hero::after {
    content: "";
    position: absolute;
    left: -8%;
    right: -8%;
    bottom: -95px;
    height: 180px;
    background: #fff;
    transform: rotate(-4deg);
    z-index: -1;
}

.hero-grid {
    display: grid;
    gap: 32px;
    align-items: center;
}

.hero-copy h1 {
    margin: 0 0 18px;
    font-size: clamp(36px, 10vw, 68px);
    line-height: 1.04;
    letter-spacing: -0.04em;
}

.hero-copy p {
    margin: 0 0 24px;
    max-width: 620px;
    color: rgba(255,255,255,.86);
    font-size: 18px;
}

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

.hero-tags {
    margin-top: 22px;
}

.hero-tags span,
.visual-tags span,
.tag-row span {
    display: inline-flex;
    align-items: center;
    min-height: 30px;
    padding: 5px 12px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 700;
}

.hero-tags span,
.visual-tags span {
    background: rgba(255,255,255,.16);
    border: 1px solid rgba(255,255,255,.24);
    color: #fff;
}

.hero-visual {
    position: relative;
}

.app-card {
    position: relative;
    padding: 18px;
    border-radius: 36px;
    background: rgba(255,255,255,.16);
    border: 1px solid rgba(255,255,255,.24);
    box-shadow: 0 26px 80px rgba(18, 24, 50, .24);
}

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

.float-card {
    position: absolute;
    right: 10px;
    bottom: -16px;
    width: min(210px, 62%);
    padding: 14px;
    border-radius: 20px;
    background: #fff;
    color: #202B3D;
    box-shadow: var(--shadow);
}

.float-card strong {
    display: block;
    margin-bottom: 4px;
}

.float-card small {
    color: var(--muted);
}

.product-highlights {
    margin-top: -28px;
    position: relative;
    z-index: 2;
}

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

.highlight-card,
.info-card,
.risk-card,
.faq-item,
.step-card,
.help-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    padding: 22px;
    box-shadow: 0 12px 30px rgba(34, 43, 58, .06);
}

.highlight-card .label,
.info-card .label {
    display: inline-flex;
    padding: 3px 10px;
    margin-bottom: 10px;
    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,
.step-card h3,
.help-card h3 {
    margin: 0 0 8px;
    font-size: 20px;
}

.highlight-card p,
.info-card p,
.risk-card p,
.step-card p,
.help-card p {
    margin: 0 0 12px;
    color: var(--muted);
}

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

.feature-panel {
    display: grid;
    gap: 26px;
    align-items: center;
    padding: 26px;
    border-radius: var(--radius-lg);
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.feature-panel.alt {
    background: #F8FAFF;
}

.feature-panel h2 {
    margin: 0 0 14px;
    font-size: clamp(28px, 6vw, 44px);
    line-height: 1.18;
}

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

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

.feature-points li {
    list-style: none;
    position: relative;
    padding-left: 26px;
    color: #41506A;
}

.feature-points li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 11px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--blue);
}

.feature-image {
    overflow: hidden;
    border-radius: 28px;
    background: var(--soft-blue);
}

.feature-image img {
    width: 100%;
}

.high-speed-section,
.global-nodes-section,
.privacy-protection-section,
.multi-device-section,
.encryption-protocol-section {
    background: linear-gradient(180deg, #FFFFFF 0%, #F6F8FC 100%);
}

.privacy-grid,
.no-log-grid,
.device-grid,
.protocol-grid,
.risk-grid,
.faq-grid,
.article-grid,
.page-card-grid {
    display: grid;
    gap: 18px;
}

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

.privacy-panel .feature-image {
    margin-top: 20px;
}

.no-log-policy-section .info-card {
    border-top: 4px solid var(--blue);
}

.device-showcase {
    padding: 24px;
    border-radius: var(--radius-lg);
    background: var(--brand-gradient);
    color: #fff;
}

.device-showcase p {
    color: rgba(255,255,255,.82);
}

.protocol-panel {
    border-radius: var(--radius-lg);
    padding: 26px;
    background: #172033;
    color: #fff;
    overflow: hidden;
}

.protocol-panel p {
    color: rgba(255,255,255,.76);
}

.protocol-lines {
    display: grid;
    gap: 12px;
    margin-top: 22px;
}

.protocol-lines span {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    padding: 14px;
    border-radius: 16px;
    background: rgba(255,255,255,.08);
    color: rgba(255,255,255,.88);
}

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

.step-card {
    position: relative;
    padding-top: 56px;
}

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

.safety-panel {
    padding: 28px;
    border-radius: var(--radius-lg);
    background: #F8FAFF;
    border: 1px solid var(--line);
}

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

.risk-card strong {
    display: block;
    margin: 8px 0 4px;
    color: #23304A;
}

.faq-item h3 {
    margin: 0 0 8px;
    font-size: 19px;
}

.faq-item p {
    margin: 0;
    color: var(--muted);
}

.cta-section {
    margin: 54px auto 0;
    padding: 38px 24px;
    border-radius: var(--radius-lg);
    text-align: center;
    background: var(--brand-gradient);
    color: #fff;
}

.cta-section p {
    margin: 0 auto 22px;
    max-width: 700px;
    color: rgba(255,255,255,.84);
}

.page-hero {
    padding: 56px 0 36px;
    background: linear-gradient(180deg, #F3F7FF 0%, #FFFFFF 100%);
}

.page-hero h1 {
    margin: 0 0 14px;
    font-size: clamp(32px, 7vw, 54px);
    line-height: 1.12;
    letter-spacing: -0.03em;
}

.page-hero p {
    margin: 0;
    color: var(--muted);
    font-size: 18px;
}

.article-grid {
    grid-template-columns: 1fr;
    align-items: start;
}

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

.article-content h2 {
    margin: 12px 0 4px;
    font-size: 26px;
}

.article-content p,
.article-content li {
    color: #4A5870;
}

.article-panel,
.sidebar-panel {
    border: 1px solid var(--line);
    background: #fff;
    border-radius: var(--radius-md);
    padding: 24px;
    box-shadow: 0 12px 30px rgba(34, 43, 58, .05);
}

.sidebar-panel {
    position: static;
}

.check-list,
.simple-list {
    padding: 0;
    margin: 16px 0 0;
    display: grid;
    gap: 10px;
}

.check-list li,
.simple-list li {
    list-style: none;
    padding: 12px 14px;
    border-radius: 16px;
    background: #F7F9FC;
    color: #46556E;
}

.download-page-panel {
    display: grid;
    gap: 22px;
    padding: 28px;
    border-radius: var(--radius-lg);
    background: #fff;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.download-page-panel .download-btn {
    width: fit-content;
}

.site-footer {
    margin-top: 70px;
    padding: 38px 0;
    background: #F6F8FC;
    border-top: 1px solid var(--line);
}

.footer-inner {
    width: min(1120px, calc(100% - 36px));
    margin: 0 auto;
    display: grid;
    gap: 22px;
}

.footer-brand {
    display: flex;
    gap: 12px;
    align-items: center;
}

.footer-brand img {
    width: 42px;
    height: 42px;
    object-fit: cover;
    border-radius: 12px;
}

.footer-brand p,
.footer-note {
    margin: 4px 0 0;
    color: var(--muted);
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 10px 16px;
}

.footer-links a {
    color: #40506B;
    font-weight: 700;
}

@media (min-width: 700px) {
    .highlight-grid,
    .privacy-grid,
    .no-log-grid,
    .device-grid,
    .protocol-grid,
    .risk-grid,
    .faq-grid,
    .page-card-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

@media (min-width: 980px) {
    .nav-toggle-label {
        display: none;
    }

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

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

    .hero-grid,
    .feature-panel,
    .article-grid {
        grid-template-columns: minmax(0, 1fr) minmax(0, 0.9fr);
    }

    .hero-grid {
        gap: 54px;
    }

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

    .feature-panel {
        padding: 38px;
    }

    .feature-panel.reverse .feature-image {
        order: -1;
    }

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

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

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

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

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

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

@media (max-width: 460px) {
    .section {
        padding: 46px 0;
    }

    .download-btn {
        width: 100%;
    }

    .hero-copy .download-btn,
    .cta-section .download-btn,
    .download-page-panel .download-btn {
        width: 100%;
    }

    .float-card {
        position: static;
        width: 100%;
        margin-top: 12px;
    }

    .protocol-lines span {
        flex-direction: column;
    }
}