* {
    box-sizing: border-box;
}

:root {
    --brand-blue: #2980FE;
    --brand-blue-hover: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1f2937;
    --muted: #64748b;
    --light: #f6f8fb;
    --line: #e5eaf2;
    --card: #ffffff;
    --deep: #111827;
}

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: 1.7;
    overflow-x: hidden;
}

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

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

.container {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.94);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(16px);
}

.nav-wrap {
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: var(--deep);
    letter-spacing: 0.02em;
}

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

.main-nav {
    display: none;
    width: 100%;
    padding: 14px 0 18px;
}

.main-nav a {
    display: block;
    padding: 10px 4px;
    color: #475569;
    font-size: 15px;
    border-bottom: 1px solid #edf1f7;
}

.main-nav a.active,
.main-nav a:hover {
    color: var(--brand-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: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    cursor: pointer;
    background: #fff;
}

.nav-toggle-label span {
    width: 18px;
    height: 2px;
    border-radius: 2px;
    background: #334155;
}

.nav-toggle:checked ~ .main-nav {
    display: block;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    width: auto;
    padding: 14px 18px 16px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 20px;
    box-shadow: 0 20px 50px rgba(15, 23, 42, 0.12);
}

.gradient-bg,
.vpn-dashboard-hero,
.cta-section {
    background: var(--gradient);
}

.section {
    padding: 56px 0;
}

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

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

.section-title .eyebrow,
.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 5px 12px;
    border-radius: 999px;
    color: var(--brand-blue);
    background: #eef5ff;
    font-weight: 700;
    font-size: 13px;
    margin-bottom: 12px;
}

.section-title h2,
.page-hero h1,
.vpn-dashboard-hero h1 {
    margin: 0 0 14px;
    line-height: 1.18;
    color: var(--deep);
}

.section-title h2 {
    font-size: clamp(28px, 4vw, 42px);
}

.section-title p,
.page-hero p,
.card p,
.feature-copy p,
.panel p,
.faq-item p {
    color: var(--muted);
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: var(--brand-blue);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(41, 128, 254, 0.24);
    transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

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

.text-link {
    color: var(--brand-blue);
    font-weight: 700;
}

.vpn-dashboard-hero {
    color: #fff;
    padding: 68px 0 54px;
    position: relative;
    overflow: hidden;
}

.vpn-dashboard-hero::before,
.vpn-dashboard-hero::after {
    content: "";
    position: absolute;
    width: 280px;
    height: 280px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.12);
    filter: blur(2px);
}

.vpn-dashboard-hero::before {
    right: -90px;
    top: -70px;
}

.vpn-dashboard-hero::after {
    left: -120px;
    bottom: -150px;
}

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

.vpn-dashboard-hero h1 {
    color: #fff;
    font-size: clamp(36px, 7vw, 64px);
    letter-spacing: -0.04em;
}

.hero-copy p {
    max-width: 640px;
    margin: 0 0 22px;
    color: rgba(255, 255, 255, 0.88);
    font-size: 17px;
}

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

.hero-tags span {
    padding: 7px 12px;
    border-radius: 999px;
    color: #fff;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.22);
    font-size: 14px;
}

.hero-console {
    position: relative;
    padding: 18px;
    border-radius: 30px;
    background: rgba(255, 255, 255, 0.16);
    border: 1px solid rgba(255, 255, 255, 0.22);
    box-shadow: 0 24px 70px rgba(23, 30, 80, 0.22);
}

.hero-device {
    border-radius: 24px;
    overflow: hidden;
    background: #fff;
    padding: 10px;
}

.status-stack {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
    margin-top: 14px;
}

.status-card {
    display: flex;
    justify-content: space-between;
    gap: 14px;
    padding: 14px;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.92);
    color: var(--text);
    border: 1px solid rgba(255, 255, 255, 0.6);
}

.status-card strong {
    display: block;
    color: var(--deep);
    font-size: 15px;
}

.status-card span {
    color: var(--muted);
    font-size: 13px;
}

.status-dot {
    width: 12px;
    height: 12px;
    margin-top: 7px;
    border-radius: 50%;
    background: #22c55e;
    box-shadow: 0 0 0 6px rgba(34, 197, 94, 0.12);
    flex: 0 0 auto;
}

.service-index {
    margin-top: -28px;
    position: relative;
    z-index: 3;
}

.category-grid,
.service-grid,
.risk-grid,
.faq-grid,
.info-grid,
.related-grid {
    display: grid;
    gap: 18px;
}

.service-card,
.card,
.panel,
.faq-item,
.risk-card,
.step-card,
.related-card,
.check-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 24px;
    padding: 22px;
    box-shadow: 0 16px 42px rgba(15, 23, 42, 0.06);
}

.service-card {
    min-height: 168px;
}

.service-card .tag,
.card .tag {
    display: inline-flex;
    color: var(--brand-blue);
    background: #eef5ff;
    border-radius: 999px;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 800;
    margin-bottom: 12px;
}

.service-card h3,
.card h3,
.panel h3,
.risk-card h3,
.step-card h3,
.related-card h3,
.check-card h3 {
    margin: 0 0 10px;
    color: var(--deep);
    line-height: 1.35;
}

.feature-section {
    padding: 64px 0;
}

.feature-grid {
    display: grid;
    gap: 26px;
    align-items: center;
}

.feature-card {
    border-radius: 30px;
    overflow: hidden;
    border: 1px solid var(--line);
    background: #fff;
    box-shadow: 0 22px 60px rgba(15, 23, 42, 0.08);
}

.feature-card img {
    width: 100%;
    aspect-ratio: 16 / 11;
    object-fit: cover;
}

.feature-copy h2 {
    font-size: clamp(28px, 4vw, 42px);
    line-height: 1.2;
    margin: 0 0 14px;
    color: var(--deep);
}

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

.feature-list li,
.clean-list li {
    position: relative;
    padding-left: 24px;
    color: #334155;
}

.feature-list li::before,
.clean-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 10px;
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--brand-blue);
    box-shadow: 0 0 0 5px #eaf3ff;
}

.privacy-protection-section .panel,
.no-log-policy-section .panel,
.encryption-protocol-section .panel {
    background: linear-gradient(180deg, #ffffff 0%, #f8fbff 100%);
}

.safety-panel {
    border-radius: 30px;
    border: 1px solid #d8e6fb;
    background: linear-gradient(135deg, #f7fbff 0%, #ffffff 60%);
    padding: 24px;
}

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

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

.mini-metric strong {
    display: block;
    color: var(--deep);
}

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

.step-card {
    position: relative;
    padding-top: 24px;
}

.step-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 12px;
    color: #fff;
    background: var(--brand-blue);
    font-weight: 800;
    margin-bottom: 12px;
}

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

.risk-card .suggestion {
    color: #334155;
    font-weight: 700;
    margin-top: 12px;
}

.faq-item h3 {
    margin: 0 0 8px;
    color: var(--deep);
}

.cta-section {
    padding: 54px 0;
    color: #fff;
    text-align: center;
    border-radius: 0;
}

.cta-section h2 {
    margin: 0 0 12px;
    font-size: clamp(28px, 4vw, 42px);
    color: #fff;
}

.cta-section p {
    margin: 0 auto 22px;
    max-width: 720px;
    color: rgba(255, 255, 255, 0.86);
}

.page-hero {
    padding: 58px 0 36px;
    background: linear-gradient(180deg, #f6f9ff 0%, #ffffff 100%);
    border-bottom: 1px solid var(--line);
}

.page-hero h1 {
    font-size: clamp(34px, 6vw, 54px);
    letter-spacing: -0.03em;
    max-width: 880px;
}

.page-hero p {
    max-width: 760px;
    font-size: 17px;
}

.page-layout {
    display: grid;
    gap: 24px;
    padding: 48px 0 64px;
}

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

.article-body .content-block {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 26px;
    padding: 24px;
}

.article-body h2 {
    margin: 0 0 12px;
    color: var(--deep);
    font-size: clamp(23px, 3vw, 32px);
}

.article-body p {
    color: #475569;
    margin: 0 0 12px;
}

.side-panel {
    display: grid;
    gap: 16px;
    align-content: start;
}

.badge {
    display: inline-flex;
    padding: 5px 12px;
    border-radius: 999px;
    background: #eef5ff;
    color: var(--brand-blue);
    font-weight: 800;
    font-size: 13px;
}

.download-panel {
    text-align: center;
    background: linear-gradient(180deg, #ffffff 0%, #f4f8ff 100%);
}

.download-page .process-steps {
    counter-reset: install;
}

.site-footer {
    background: #111827;
    color: #cbd5e1;
    padding: 44px 0 26px;
}

.footer-grid {
    display: grid;
    gap: 24px;
}

.footer-brand {
    color: #fff;
    font-size: 22px;
    font-weight: 900;
    margin-bottom: 10px;
}

.site-footer h3 {
    color: #fff;
    margin: 0 0 12px;
}

.site-footer a {
    display: block;
    color: #cbd5e1;
    margin: 8px 0;
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: 30px;
    padding-top: 18px;
    font-size: 14px;
    color: #94a3b8;
}

@media (min-width: 640px) {
    .category-grid,
    .service-grid,
    .risk-grid,
    .faq-grid,
    .info-grid,
    .related-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

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

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

    .main-nav,
    .nav-toggle:checked ~ .main-nav {
        display: flex;
        position: static;
        width: auto;
        padding: 0;
        background: transparent;
        border: 0;
        box-shadow: none;
        gap: 4px;
        align-items: center;
    }

    .main-nav a {
        border-bottom: 0;
        padding: 8px 10px;
        border-radius: 999px;
        font-size: 14px;
    }

    .main-nav a.active,
    .main-nav a:hover {
        background: #eef5ff;
    }

    .hero-grid,
    .feature-grid,
    .page-layout {
        grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    }

    .feature-grid.reverse {
        grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
    }

    .feature-grid.reverse .feature-card {
        order: 2;
    }

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

    .service-index .category-grid .service-card:first-child,
    .service-index .category-grid .service-card:nth-child(4) {
        grid-column: span 2;
    }

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

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

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

    .footer-grid {
        grid-template-columns: 1.4fr repeat(3, 1fr);
    }
}

@media (min-width: 1100px) {
    .main-nav a {
        padding: 8px 12px;
    }

    .hero-console {
        transform: translateY(12px);
    }
}