* {
    box-sizing: border-box;
}

:root {
    --brand-blue: #2980FE;
    --brand-blue-dark: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1f2937;
    --muted: #667085;
    --soft: #f5f7fb;
    --soft-blue: #eef5ff;
    --line: #e5e7eb;
    --card: #ffffff;
    --shadow: 0 18px 48px rgba(31, 41, 55, .08);
    --radius-lg: 28px;
    --radius-md: 20px;
}

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: #fff;
    line-height: 1.75;
    overflow-x: hidden;
}

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

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

p {
    margin: 0 0 16px;
}

h1, h2, h3 {
    line-height: 1.25;
    margin: 0 0 16px;
    color: #111827;
}

h1 {
    font-size: clamp(2rem, 8vw, 4.7rem);
    letter-spacing: -0.04em;
}

h2 {
    font-size: clamp(1.65rem, 5vw, 3rem);
    letter-spacing: -0.03em;
}

h3 {
    font-size: 1.15rem;
}

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

.narrow-container {
    width: min(100% - 32px, 880px);
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255, 255, 255, .92);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(229, 231, 235, .8);
}

.header-inner {
    width: min(100% - 28px, 1180px);
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 1.15rem;
    color: #111827;
}

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

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

.nav-toggle-label {
    display: inline-flex;
    width: 44px;
    height: 44px;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    cursor: pointer;
}

.nav-toggle-label span {
    display: block;
    width: 24px;
    height: 2px;
    background: #111827;
    border-radius: 99px;
}

.main-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    display: none;
    flex-direction: column;
    gap: 6px;
    padding: 16px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: #fff;
    box-shadow: var(--shadow);
}

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

.main-nav a {
    padding: 10px 12px;
    color: #374151;
    border-radius: 12px;
    font-size: .95rem;
}

.main-nav a.active,
.main-nav a:hover {
    color: var(--brand-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(--brand-blue);
    color: #fff;
    font-weight: 700;
    box-shadow: 0 14px 32px rgba(41, 128, 254, .28);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    background: var(--brand-blue-dark);
    transform: translateY(-2px);
    box-shadow: 0 16px 36px rgba(23, 104, 232, .32);
}

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

.badge,
.category-badge,
.tag {
    display: inline-flex;
    align-items: center;
    width: fit-content;
    gap: 6px;
    border-radius: 999px;
    padding: 6px 12px;
    background: rgba(41, 128, 254, .1);
    color: var(--brand-blue);
    font-size: .84rem;
    font-weight: 700;
}

.vpn-network-hero {
    position: relative;
    overflow: hidden;
    color: #fff;
    background: var(--gradient);
}

.vpn-network-hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image: radial-gradient(circle at 20% 25%, rgba(255,255,255,.22) 0 2px, transparent 3px), radial-gradient(circle at 70% 30%, rgba(255,255,255,.2) 0 2px, transparent 3px), radial-gradient(circle at 80% 70%, rgba(255,255,255,.18) 0 2px, transparent 3px), linear-gradient(120deg, transparent 15%, rgba(255,255,255,.16) 16%, transparent 17%, transparent 58%, rgba(255,255,255,.12) 59%, transparent 60%);
    opacity: .75;
}

.hero-inner {
    position: relative;
    z-index: 1;
    width: min(100% - 32px, 1180px);
    min-height: 680px;
    margin: 0 auto;
    padding: 70px 0;
    display: grid;
    grid-template-columns: 1fr;
    gap: 36px;
    align-items: center;
}

.hero-content h1,
.hero-content h2,
.vpn-network-hero h1 {
    color: #fff;
}

.hero-content p {
    max-width: 680px;
    color: rgba(255,255,255,.88);
    font-size: 1.06rem;
}

.hero-tags,
.status-list,
.section-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 20px 0 26px;
}

.hero-tags span,
.status-list span,
.section-tags span {
    border-radius: 999px;
    padding: 7px 12px;
    background: rgba(255,255,255,.16);
    color: #fff;
    border: 1px solid rgba(255,255,255,.22);
    font-size: .88rem;
}

.hero-visual {
    position: relative;
    min-height: 360px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-visual img {
    width: min(430px, 86vw);
    border-radius: 28px;
    filter: drop-shadow(0 30px 55px rgba(18, 33, 88, .35));
}

.floating-card {
    position: absolute;
    border-radius: 18px;
    padding: 12px 15px;
    background: rgba(255,255,255,.92);
    color: #111827;
    box-shadow: 0 18px 40px rgba(31,41,55,.16);
    font-size: .88rem;
    font-weight: 700;
}

.float-one { top: 18px; left: 2%; }
.float-two { top: 18%; right: 0; }
.float-three { bottom: 20%; left: 0; }
.float-four { bottom: 4%; right: 9%; }

.section {
    padding: 76px 0;
}

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

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

.section-heading.center {
    text-align: center;
    margin-inline: auto;
}

.section-heading p,
.page-hero p,
.card p,
.feature-card p,
.info-card p,
.step-card p,
.risk-card p,
.faq-item p {
    color: var(--muted);
}

.node-overview {
    margin-top: -58px;
    position: relative;
    z-index: 2;
}

.node-overview-grid,
.card-grid,
.risk-grid,
.faq-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
}

.node-card,
.card,
.info-card,
.step-card,
.risk-card,
.faq-item,
.side-panel,
.download-panel {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    padding: 22px;
    box-shadow: 0 12px 34px rgba(31,41,55,.06);
}

.node-card strong {
    display: inline-flex;
    margin-bottom: 10px;
    color: var(--brand-blue);
}

.feature-section,
.vpn-connection-section,
.global-nodes-section,
.high-speed-section,
.privacy-protection-section,
.multi-device-section,
.encryption-protocol-section {
    display: grid;
    grid-template-columns: 1fr;
    gap: 28px;
    align-items: center;
}

.feature-media,
.map-panel,
.security-panel,
.tech-panel,
.speed-panel,
.device-panel {
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-lg);
    padding: 22px;
    background: linear-gradient(145deg, #ffffff, #eef5ff);
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.feature-media img,
.map-panel img,
.security-panel img,
.tech-panel img,
.speed-panel img,
.device-panel img {
    margin: 0 auto;
    border-radius: 22px;
}

.map-panel::before,
.tech-panel::before {
    content: "";
    position: absolute;
    inset: 16px;
    border-radius: 24px;
    background-image: radial-gradient(circle at 18% 20%, rgba(41,128,254,.18) 0 5px, transparent 6px), radial-gradient(circle at 68% 28%, rgba(123,78,241,.16) 0 5px, transparent 6px), radial-gradient(circle at 42% 70%, rgba(184,77,218,.15) 0 5px, transparent 6px), linear-gradient(135deg, transparent 20%, rgba(41,128,254,.12) 21%, transparent 22%, transparent 61%, rgba(123,78,241,.12) 62%, transparent 63%);
    pointer-events: none;
}

.list-check,
.clean-list {
    padding: 0;
    margin: 18px 0 0;
    list-style: none;
}

.list-check li,
.clean-list li {
    position: relative;
    padding-left: 24px;
    margin: 10px 0;
    color: #475467;
}

.list-check li::before,
.clean-list li::before {
    content: "";
    width: 8px;
    height: 8px;
    position: absolute;
    left: 2px;
    top: .75em;
    border-radius: 50%;
    background: var(--brand-blue);
}

.no-log-policy-section .card-grid {
    margin-top: 20px;
}

.process-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
    counter-reset: step;
}

.step-card {
    position: relative;
    padding-top: 52px;
}

.step-card .step-number {
    position: absolute;
    top: 18px;
    left: 22px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 12px;
    background: var(--brand-blue);
    color: #fff;
    font-weight: 800;
}

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

.cta-section {
    position: relative;
    overflow: hidden;
    padding: 72px 0;
    background: var(--gradient);
    color: #fff;
}

.cta-section h2,
.cta-section p {
    color: #fff;
}

.cta-panel {
    width: min(100% - 32px, 920px);
    margin: 0 auto;
    text-align: center;
}

.page-main {
    background: #fff;
}

.page-hero {
    padding: 64px 0 36px;
    background: linear-gradient(180deg, #f4f8ff 0%, #fff 100%);
}

.page-hero .narrow-container {
    display: grid;
    gap: 14px;
}

.page-layout {
    width: min(100% - 32px, 1120px);
    margin: 0 auto;
    padding: 36px 0 78px;
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

.article-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    padding: clamp(24px, 5vw, 42px);
    box-shadow: 0 18px 46px rgba(31,41,55,.06);
}

.article-card h2 {
    font-size: clamp(1.45rem, 4vw, 2.2rem);
    margin-top: 18px;
}

.article-card .download-row {
    margin-top: 28px;
}

.side-panel {
    height: fit-content;
    background: linear-gradient(180deg, #fff, #f7faff);
}

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

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

.notice-box,
.tip-box {
    margin: 22px 0;
    padding: 18px;
    border-radius: 18px;
    background: var(--soft-blue);
    border: 1px solid rgba(41,128,254,.18);
    color: #37526f;
}

.download-page .download-panel {
    text-align: center;
    padding: clamp(28px, 6vw, 56px);
}

.download-steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    margin: 28px 0;
}

.download-steps .step-card {
    text-align: left;
}

.faq-list {
    display: grid;
    gap: 16px;
}

.faq-item h2,
.faq-item h3 {
    font-size: 1.1rem;
    margin-bottom: 8px;
}

.site-footer {
    background: #111827;
    color: rgba(255,255,255,.74);
    padding-top: 54px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 26px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 14px;
    color: #fff;
}

.footer-brand img {
    width: 36px;
    height: 36px;
    border-radius: 12px;
    object-fit: cover;
}

.site-footer h3 {
    color: #fff;
    font-size: 1rem;
}

.site-footer a {
    display: block;
    color: rgba(255,255,255,.72);
    padding: 5px 0;
}

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

.footer-bottom {
    margin-top: 36px;
    padding: 18px 16px;
    border-top: 1px solid rgba(255,255,255,.12);
    text-align: center;
}

.footer-bottom p {
    margin: 0;
    color: rgba(255,255,255,.58);
}

@media (min-width: 680px) {
    .node-overview-grid,
    .card-grid,
    .risk-grid,
    .faq-grid,
    .download-steps {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

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

    .main-nav a {
        padding: 9px 10px;
        white-space: nowrap;
    }

    .hero-inner {
        grid-template-columns: 1.02fr .98fr;
        min-height: 720px;
        padding: 82px 0;
    }

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

    .feature-section,
    .vpn-connection-section,
    .global-nodes-section,
    .high-speed-section,
    .privacy-protection-section,
    .multi-device-section,
    .encryption-protocol-section {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 46px;
    }

    .global-nodes-section,
    .privacy-protection-section,
    .encryption-protocol-section {
        grid-template-columns: 1.05fr .95fr;
    }

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

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

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

    .page-layout {
        grid-template-columns: minmax(0, 1fr) 300px;
        align-items: start;
    }

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