* {
    box-sizing: border-box;
}

:root {
    --brand-gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --text: #202638;
    --muted: #667085;
    --light: #F6F8FC;
    --line: #E6EAF2;
    --panel: #FFFFFF;
    --soft-blue: #EFF5FF;
    --radius-lg: 30px;
    --radius-md: 22px;
    --shadow: 0 18px 55px rgba(35, 55, 120, 0.12);
}

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: 1.75;
    overflow-x: hidden;
}

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

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

p {
    margin: 0 0 16px;
    color: var(--muted);
}

h1, h2, h3 {
    margin: 0;
    color: var(--text);
    line-height: 1.2;
}

ul, ol {
    margin: 0;
    padding-left: 20px;
    color: var(--muted);
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(230, 234, 242, 0.9);
}

.header-inner {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: 0.02em;
    color: #172033;
    flex-shrink: 0;
}

.brand-logo {
    width: 42px;
    height: 42px;
    border-radius: 14px;
    object-fit: cover;
    box-shadow: 0 8px 20px rgba(41, 128, 254, 0.16);
}

.brand-text {
    font-size: 20px;
}

.nav-toggle {
    width: 46px;
    height: 42px;
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 14px;
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    width: 20px;
    height: 2px;
    border-radius: 2px;
    background: #25304A;
}

.primary-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 78px;
    display: none;
    flex-direction: column;
    gap: 6px;
    padding: 14px;
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 22px;
    box-shadow: var(--shadow);
}

.primary-nav.is-open {
    display: flex;
}

.primary-nav a {
    padding: 11px 12px;
    border-radius: 14px;
    font-size: 15px;
    color: #42506B;
}

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

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

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

.section {
    padding: 66px 0;
}

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

.section-heading {
    margin-bottom: 26px;
}

.section-heading.center {
    text-align: center;
    width: min(760px, 100%);
    margin-left: auto;
    margin-right: auto;
}

.section-eyebrow,
.page-badge,
.card-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--blue);
    background: var(--soft-blue);
    border: 1px solid rgba(41, 128, 254, 0.14);
    border-radius: 999px;
    font-size: 13px;
    font-weight: 700;
    padding: 6px 12px;
    margin-bottom: 12px;
}

.section-heading h2,
.content-block h2 {
    font-size: clamp(26px, 5vw, 42px);
    letter-spacing: -0.04em;
    margin-bottom: 12px;
}

.section-heading p {
    font-size: 16px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 26px;
    border-radius: 999px;
    background: var(--blue);
    color: #FFFFFF;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(41, 128, 254, 0.26);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    background: var(--blue-dark);
    color: #FFFFFF;
    transform: translateY(-2px);
    box-shadow: 0 18px 34px rgba(23, 104, 232, 0.28);
}

.text-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--blue);
    font-weight: 700;
}

.text-link::after {
    content: "›";
    font-size: 18px;
}

.vpn-saas-hero {
    position: relative;
    padding: 38px 0 78px;
    overflow: hidden;
    background: linear-gradient(180deg, #FFFFFF 0%, #F7F9FF 100%);
}

.vpn-saas-hero::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    min-height: 640px;
    background: var(--brand-gradient);
    clip-path: polygon(0 0, 100% 0, 100% 74%, 0 100%);
}

.hero-grid {
    position: relative;
    z-index: 1;
    display: grid;
    gap: 34px;
    align-items: center;
}

.hero-copy {
    color: #fff;
    padding: 32px 0 4px;
}

.hero-copy h1 {
    color: #fff;
    font-size: clamp(38px, 10vw, 68px);
    letter-spacing: -0.06em;
    margin-bottom: 18px;
}

.hero-copy p {
    color: rgba(255,255,255,0.86);
    font-size: 17px;
    max-width: 650px;
}

.hero-actions {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 14px;
    margin: 26px 0 18px;
}

.hero-note {
    color: rgba(255,255,255,0.84);
    font-size: 14px;
}

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

.security-tags span {
    color: #fff;
    border: 1px solid rgba(255,255,255,0.28);
    background: rgba(255,255,255,0.13);
    border-radius: 999px;
    padding: 8px 12px;
    font-size: 14px;
}

.hero-product {
    position: relative;
    border-radius: 36px;
    background: rgba(255, 255, 255, 0.18);
    padding: 18px;
    box-shadow: 0 30px 80px rgba(28, 38, 92, 0.24);
}

.product-glass {
    border-radius: 30px;
    padding: 20px;
    background: rgba(255,255,255,0.92);
    border: 1px solid rgba(255,255,255,0.56);
}

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

.float-chip {
    position: absolute;
    z-index: 2;
    background: #fff;
    color: #23304B;
    border: 1px solid var(--line);
    box-shadow: 0 14px 40px rgba(17, 32, 88, 0.14);
    border-radius: 999px;
    padding: 9px 13px;
    font-size: 13px;
    font-weight: 700;
}

.float-chip.one { left: 18px; top: 26px; }
.float-chip.two { right: 16px; top: 22%; }
.float-chip.three { left: 8%; bottom: 18%; }
.float-chip.four { right: 18px; bottom: 28px; }

.product-highlights {
    margin-top: -34px;
    position: relative;
    z-index: 2;
}

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

.highlight-card,
.feature-card,
.risk-card,
.step-card,
.faq-item,
.info-card,
.sidebar-card,
.download-panel,
.notice-box,
.check-card {
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    box-shadow: 0 14px 36px rgba(30, 48, 92, 0.07);
}

.highlight-card {
    padding: 22px;
}

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

.highlight-card p {
    min-height: 72px;
}

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

.feature-panel {
    border-radius: var(--radius-lg);
    background: #fff;
    border: 1px solid var(--line);
    padding: 24px;
    box-shadow: var(--shadow);
}

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

.bullet-list {
    display: grid;
    gap: 10px;
    margin: 20px 0;
}

.bullet-list li {
    list-style: none;
    position: relative;
    padding: 11px 12px 11px 36px;
    border-radius: 16px;
    background: #F8FAFE;
    border: 1px solid #EDF1F8;
    color: #4D5A73;
}

.bullet-list li::before {
    content: "";
    position: absolute;
    left: 14px;
    top: 18px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--blue);
}

.high-speed-section {
    background: linear-gradient(180deg, #F6F9FF 0%, #FFFFFF 100%);
}

.speed-card {
    display: grid;
    gap: 18px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 34px;
    padding: 20px;
    box-shadow: var(--shadow);
}

.speed-metrics {
    display: grid;
    gap: 12px;
}

.metric {
    padding: 18px;
    border-radius: 20px;
    background: #F8FAFE;
    border: 1px solid #EDF1F8;
}

.metric strong {
    display: block;
    font-size: 24px;
    color: var(--blue);
    margin-bottom: 4px;
}

.nodes-grid,
.privacy-grid,
.no-log-grid,
.device-grid,
.protocol-grid,
.risk-grid,
.related-grid,
.article-card-grid,
.check-grid {
    display: grid;
    gap: 16px;
}

.global-nodes-section .feature-panel {
    background: linear-gradient(180deg, #FFFFFF 0%, #F4F7FF 100%);
}

.privacy-protection-section {
    background: #F7F9FD;
}

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

.info-card,
.feature-card,
.risk-card,
.step-card,
.check-card {
    padding: 22px;
}

.info-card h3,
.feature-card h3,
.risk-card h3,
.step-card h3,
.check-card h3 {
    font-size: 19px;
    margin-bottom: 8px;
}

.info-card p,
.feature-card p,
.risk-card p,
.step-card p,
.check-card p {
    margin-bottom: 10px;
}

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

.device-showcase {
    background: var(--brand-gradient);
    border-radius: 36px;
    padding: 22px;
    color: #fff;
    box-shadow: 0 28px 70px rgba(72, 82, 213, 0.18);
}

.device-showcase h3,
.device-showcase p {
    color: #fff;
}

.device-showcase img {
    border-radius: 28px;
    margin-bottom: 18px;
}

.tech-panel {
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: 36px;
    padding: 24px;
    box-shadow: var(--shadow);
}

.protocol-row {
    display: grid;
    gap: 12px;
    margin-top: 18px;
}

.protocol-item {
    padding: 18px;
    border-radius: 20px;
    background: #F8FAFE;
    border: 1px solid #EDF1F8;
}

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

.step-card {
    position: relative;
    padding-left: 70px;
}

.step-number {
    position: absolute;
    left: 22px;
    top: 22px;
    width: 34px;
    height: 34px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--blue);
    color: #fff;
    font-weight: 800;
}

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

.risk-card strong {
    display: block;
    color: #39465E;
    margin-bottom: 8px;
}

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

.faq-item {
    padding: 22px;
}

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

.cta-section {
    padding: 68px 0;
}

.cta-panel {
    position: relative;
    overflow: hidden;
    border-radius: 38px;
    padding: 34px 24px;
    text-align: center;
    background: var(--brand-gradient);
    box-shadow: 0 32px 82px rgba(73, 80, 210, 0.23);
}

.cta-panel::after {
    content: "";
    position: absolute;
    width: 260px;
    height: 260px;
    right: -80px;
    top: -80px;
    background: rgba(255,255,255,0.16);
    border-radius: 50%;
}

.cta-panel h2,
.cta-panel p {
    position: relative;
    z-index: 1;
    color: #fff;
}

.cta-panel h2 {
    font-size: clamp(28px, 6vw, 46px);
    margin-bottom: 12px;
}

.cta-panel p {
    color: rgba(255,255,255,0.86);
    max-width: 700px;
    margin: 0 auto 22px;
}

.cta-panel .download-btn {
    position: relative;
    z-index: 1;
}

.page-hero {
    padding: 58px 0 40px;
    background: linear-gradient(180deg, #F6F9FF 0%, #FFFFFF 100%);
}

.page-hero-card {
    position: relative;
    overflow: hidden;
    border-radius: 36px;
    padding: 30px;
    background: #FFFFFF;
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.page-hero-card::before {
    content: "";
    position: absolute;
    inset: 0 0 auto 0;
    height: 8px;
    background: var(--brand-gradient);
}

.page-hero h1 {
    font-size: clamp(34px, 8vw, 58px);
    letter-spacing: -0.05em;
    margin-bottom: 16px;
}

.page-summary {
    font-size: 17px;
    max-width: 820px;
}

.article-layout {
    display: grid;
    gap: 24px;
    align-items: start;
    padding: 40px 0 70px;
}

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

.content-block,
.download-panel,
.notice-box {
    padding: 24px;
}

.content-block {
    background: #FFFFFF;
    border: 1px solid var(--line);
    border-radius: 28px;
}

.content-block h2 {
    font-size: clamp(24px, 4vw, 34px);
}

.content-block h3 {
    font-size: 21px;
    margin: 10px 0;
}

.notice-box {
    background: #F8FAFE;
    border-left: 4px solid var(--blue);
}

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

.sidebar-card {
    padding: 22px;
}

.sidebar-card h3 {
    font-size: 18px;
    margin-bottom: 12px;
}

.sidebar-card a {
    display: block;
    padding: 10px 0;
    color: var(--blue);
    font-weight: 700;
    border-top: 1px solid #EEF2F8;
}

.download-panel {
    text-align: center;
}

.download-panel h2 {
    font-size: 26px;
    margin-bottom: 12px;
}

.install-steps {
    display: grid;
    gap: 14px;
    list-style: none;
    padding: 0;
}

.install-steps li {
    padding: 18px;
    border-radius: 18px;
    background: #FFFFFF;
    border: 1px solid var(--line);
    color: #4D5A73;
}

.site-footer {
    background: #12192A;
    color: #fff;
    padding-top: 50px;
}

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

.footer-brand p {
    max-width: 420px;
    color: rgba(255,255,255,0.68);
    margin-top: 16px;
}

.footer-logo .brand-text {
    color: #fff;
}

.footer-links {
    display: grid;
    gap: 22px;
}

.footer-links h3 {
    color: #fff;
    font-size: 16px;
    margin-bottom: 12px;
}

.footer-links a {
    display: block;
    color: rgba(255,255,255,0.68);
    padding: 5px 0;
    font-size: 14px;
}

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

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    margin-top: 34px;
    padding: 18px 16px;
    text-align: center;
}

.footer-bottom p {
    margin: 0;
    color: rgba(255,255,255,0.62);
    font-size: 14px;
}

@media (min-width: 640px) {
    .highlight-grid,
    .privacy-grid,
    .no-log-grid,
    .device-grid,
    .protocol-grid,
    .risk-grid,
    .related-grid,
    .article-card-grid,
    .check-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

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

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

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

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

    .hero-grid {
        grid-template-columns: minmax(0, 1.03fr) minmax(360px, 0.97fr);
        min-height: 620px;
    }

    .hero-copy {
        padding-top: 40px;
    }

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

    .split-section,
    .speed-card,
    .privacy-panel {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .section {
        padding: 86px 0;
    }

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

    .article-layout {
        grid-template-columns: minmax(0, 1fr) 310px;
    }

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

    .content-block,
    .download-panel,
    .notice-box {
        padding: 32px;
    }

    .page-hero-card {
        padding: 46px;
    }
}

@media (min-width: 1100px) {
    .primary-nav a {
        padding: 9px 13px;
        font-size: 15px;
    }
}