* {
    box-sizing: border-box;
}

:root {
    --primary: #2980FE;
    --primary-dark: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #202738;
    --muted: #657086;
    --light: #F6F8FC;
    --line: #E5EAF3;
    --card: #FFFFFF;
    --deep: #10182B;
    --soft-blue: #EEF5FF;
    --radius: 24px;
    --shadow: 0 18px 50px rgba(21, 42, 93, 0.10);
}

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: 1.75;
    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, 0.94);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(16px);
}

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

.logo-link {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: var(--deep);
    flex: 0 0 auto;
}

.logo-img {
    width: 42px;
    height: 42px;
    border-radius: 13px;
    object-fit: cover;
    box-shadow: 0 8px 20px rgba(41, 128, 254, 0.18);
}

.logo-text {
    white-space: nowrap;
    letter-spacing: -0.02em;
}

.main-nav {
    position: absolute;
    left: 14px;
    right: 14px;
    top: 72px;
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: #fff;
    box-shadow: var(--shadow);
}

.main-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #4A556C;
    font-size: 15px;
    font-weight: 650;
}

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

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

.mobile-menu {
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 14px;
    display: grid;
    place-content: center;
    gap: 5px;
    cursor: pointer;
    background: #fff;
}

.mobile-menu span {
    width: 18px;
    height: 2px;
    background: var(--deep);
    border-radius: 10px;
}

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

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

.vpn-dashboard-hero {
    color: #fff;
    padding: 56px 0 38px;
    position: relative;
    overflow: hidden;
}

.vpn-dashboard-hero::after {
    content: "";
    position: absolute;
    inset: auto -90px -150px auto;
    width: 320px;
    height: 320px;
    background: rgba(255, 255, 255, 0.16);
    border-radius: 50%;
}

.hero-grid {
    position: relative;
    z-index: 1;
    display: grid;
    gap: 30px;
    align-items: center;
}

.hero-copy h1,
.page-hero h1 {
    margin: 0 0 16px;
    font-size: clamp(34px, 8vw, 62px);
    line-height: 1.08;
    letter-spacing: -0.05em;
}

.hero-copy p {
    margin: 0 0 24px;
    max-width: 690px;
    color: rgba(255, 255, 255, 0.88);
    font-size: 17px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: #2980FE;
    color: #fff;
    font-weight: 800;
    box-shadow: 0 16px 34px rgba(41, 128, 254, 0.28);
    transition: background 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.download-btn:hover {
    background: #1768E8;
    transform: translateY(-2px);
    box-shadow: 0 18px 42px rgba(23, 104, 232, 0.32);
}

.security-tags,
.feature-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 22px;
}

.security-tags span,
.feature-tags span,
.category-badge,
.service-tag {
    display: inline-flex;
    align-items: center;
    width: fit-content;
    padding: 7px 12px;
    border-radius: 999px;
    font-size: 13px;
    font-weight: 750;
}

.security-tags span {
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.25);
    color: #fff;
}

.hero-console {
    display: grid;
    gap: 14px;
}

.visual-card {
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.22);
    border-radius: 30px;
    padding: 18px;
    box-shadow: 0 22px 70px rgba(15, 18, 56, 0.20);
}

.visual-card img {
    margin: 0 auto;
    border-radius: 24px;
}

.status-grid {
    display: grid;
    gap: 12px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.status-card {
    background: rgba(255, 255, 255, 0.18);
    border: 1px solid rgba(255, 255, 255, 0.24);
    border-radius: 18px;
    padding: 14px;
}

.status-card strong {
    display: block;
    font-size: 15px;
}

.status-card span {
    color: rgba(255, 255, 255, 0.78);
    font-size: 13px;
}

section {
    padding: 56px 0;
}

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

.section-heading h2,
.content-block h2,
.simple-page h2 {
    margin: 0 0 10px;
    font-size: clamp(26px, 5vw, 42px);
    line-height: 1.18;
    letter-spacing: -0.035em;
    color: var(--deep);
}

.section-heading p,
.content-block p,
.simple-page p,
.card p,
.service-card p,
.feature-panel p,
.faq-item p,
.risk-card p,
.step-card p {
    color: var(--muted);
    margin: 0;
}

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

.service-card,
.card,
.feature-panel,
.risk-card,
.step-card,
.faq-item,
.aside-panel {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 12px 34px rgba(22, 40, 78, 0.06);
}

.service-card {
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 4px;
    background: var(--gradient);
}

.service-tag,
.category-badge {
    color: var(--primary);
    background: var(--soft-blue);
}

.service-card h3,
.card h3,
.feature-panel h3,
.risk-card h3,
.step-card h3,
.faq-item h3,
.aside-panel h3 {
    margin: 12px 0 8px;
    color: var(--deep);
    line-height: 1.25;
}

.link-more {
    display: inline-flex;
    margin-top: 16px;
    color: var(--primary);
    font-weight: 800;
}

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

.vpn-connection-section,
.privacy-protection-section,
.no-log-policy-section {
    background: #fff;
}

.global-nodes-section,
.high-speed-section,
.multi-device-section,
.encryption-protocol-section,
.process-section,
.risk-section,
.faq-summary-section,
.simple-muted {
    background: var(--light);
}

.image-panel {
    background: linear-gradient(145deg, #F2F7FF, #FFFFFF);
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 20px;
    box-shadow: var(--shadow);
}

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

.bullet-list li,
.check-list li,
.clean-list li {
    position: relative;
    padding-left: 24px;
    color: #475166;
}

.bullet-list li::before,
.check-list li::before,
.clean-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 12px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--primary);
}

.safety-panel {
    border-radius: 28px;
    background: #fff;
    border: 1px solid var(--line);
    padding: 24px;
    box-shadow: var(--shadow);
}

.panel-row {
    display: grid;
    gap: 14px;
}

.panel-item {
    padding: 16px;
    border-radius: 18px;
    background: var(--light);
    border-left: 4px solid var(--primary);
}

.protocol-panel {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 22px;
    box-shadow: var(--shadow);
}

.protocol-row {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
}

.protocol-row div {
    padding: 16px;
    background: #F8FAFE;
    border: 1px solid var(--line);
    border-radius: 18px;
}

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

.step-number {
    width: 38px;
    height: 38px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    color: #fff;
    background: var(--primary);
    font-weight: 900;
}

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

.faq-item h3 {
    margin-top: 0;
    font-size: 18px;
}

.cta-section {
    color: #fff;
    text-align: center;
    padding: 58px 0;
}

.cta-section h2 {
    color: #fff;
    margin: 0 0 12px;
    font-size: clamp(28px, 6vw, 44px);
    line-height: 1.18;
}

.cta-section p {
    max-width: 720px;
    margin: 0 auto 24px;
    color: rgba(255, 255, 255, 0.86);
}

.page-hero {
    padding: 54px 0 34px;
    background: linear-gradient(180deg, #F6F9FF 0%, #FFFFFF 100%);
}

.page-hero h1 {
    color: var(--deep);
    max-width: 860px;
}

.page-hero p {
    color: var(--muted);
    max-width: 760px;
    margin: 0;
    font-size: 17px;
}

.simple-page {
    padding: 44px 0 66px;
}

.article-layout {
    display: grid;
    gap: 24px;
}

.article-main {
    display: grid;
    gap: 20px;
}

.article-main .download-btn {
    justify-self: start;
}

.aside-panel {
    position: relative;
}

.notice-box {
    background: #F4F8FF;
    border: 1px solid #DCEAFF;
    border-radius: 22px;
    padding: 18px;
    color: #445069;
}

.download-panel {
    max-width: 850px;
    margin: 0 auto;
    text-align: center;
}

.download-panel .download-btn {
    margin: 22px auto 0;
}

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

.steps-list li {
    counter-increment: step;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 16px 18px 16px 58px;
    position: relative;
}

.steps-list li::before {
    content: counter(step);
    position: absolute;
    left: 16px;
    top: 16px;
    width: 28px;
    height: 28px;
    border-radius: 10px;
    background: var(--primary);
    color: #fff;
    display: grid;
    place-items: center;
    font-weight: 900;
}

.site-footer {
    background: #111827;
    color: rgba(255, 255, 255, 0.72);
    padding: 50px 0 24px;
}

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

.footer-brand {
    color: #fff;
    font-weight: 900;
    font-size: 20px;
    margin-bottom: 8px;
}

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

.site-footer a {
    display: block;
    margin: 8px 0;
    color: rgba(255, 255, 255, 0.72);
}

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

.footer-bottom {
    width: min(1120px, calc(100% - 32px));
    margin: 28px auto 0;
    padding-top: 18px;
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    font-size: 14px;
}

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

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

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

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

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

    .hero-grid,
    .split-section,
    .article-layout {
        grid-template-columns: 1.02fr 0.98fr;
    }

    .hero-console {
        grid-template-columns: 1fr;
    }

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

    .service-card.featured {
        grid-column: span 2;
    }

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

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

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

    section {
        padding: 78px 0;
    }

    .vpn-dashboard-hero {
        padding: 82px 0 70px;
    }
}

@media (min-width: 1120px) {
    .main-nav a {
        padding: 8px 12px;
    }

    .hero-console {
        transform: translateX(8px);
    }
}