:root {
    --blue: #2980FE;
    --blue-dark: #1768E8;
    --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --text: #1f2937;
    --muted: #64748b;
    --soft: #f5f7fb;
    --soft-blue: #eef5ff;
    --line: #e5eaf2;
    --white: #ffffff;
    --radius: 28px;
    --shadow: 0 18px 45px rgba(31, 41, 55, 0.08);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    background: #f8fafd;
    color: var(--text);
    line-height: 1.72;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
.container { width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.section { padding: 56px 0; }
.section-muted { background: var(--soft); }
.section-title { max-width: 760px; margin: 0 0 28px; }
.section-title.center { margin-left: auto; margin-right: auto; text-align: center; }
.eyebrow, .badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--blue);
    background: #eaf3ff;
    border: 1px solid #cfe4ff;
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 700;
}
h1, h2, h3 { line-height: 1.25; margin: 0 0 14px; color: #111827; }
h1 { font-size: clamp(34px, 7vw, 64px); letter-spacing: -1.8px; }
h2 { font-size: clamp(26px, 4vw, 40px); letter-spacing: -0.8px; }
h3 { font-size: 20px; }
p { margin: 0 0 14px; color: var(--muted); }
.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(226, 232, 240, 0.9);
}
.nav-container {
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; color: #111827; white-space: nowrap; }
.brand img { width: 38px; height: 38px; border-radius: 12px; object-fit: cover; }
.site-nav {
    display: none;
    position: absolute;
    top: 72px;
    left: 16px;
    right: 16px;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 22px;
    background: #fff;
    box-shadow: var(--shadow);
}
.site-nav a { display: block; padding: 11px 12px; color: #4b5563; border-radius: 14px; font-weight: 650; }
.site-nav a:hover, .site-nav a.active { color: var(--blue); background: #edf5ff; }
.nav-toggle { display: none; }
.nav-toggle-label { width: 44px; height: 44px; border-radius: 14px; border: 1px solid var(--line); display: grid; place-content: center; gap: 5px; cursor: pointer; }
.nav-toggle-label span { width: 20px; height: 2px; background: #1f2937; display: block; border-radius: 999px; }
.nav-toggle:checked ~ .site-nav { display: block; }
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 24px;
    border-radius: 999px;
    background: var(--blue);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(41,128,254,0.26);
    transition: transform .18s ease, background .18s ease, box-shadow .18s ease;
}
.download-btn:hover { background: var(--blue-dark); transform: translateY(-2px); box-shadow: 0 18px 34px rgba(23,104,232,0.32); }
.network-manager-hero { padding: 34px 0 44px; }
.hero-shell {
    background: var(--gradient);
    border-radius: 34px;
    overflow: hidden;
    position: relative;
    color: #fff;
    padding: 34px 22px;
    box-shadow: 0 24px 70px rgba(53,88,242,.24);
}
.hero-shell::before, .hero-shell::after {
    content: "";
    position: absolute;
    width: 260px;
    height: 260px;
    border-radius: 50%;
    background: rgba(255,255,255,.16);
    filter: blur(4px);
}
.hero-shell::before { top: -90px; right: -60px; }
.hero-shell::after { bottom: -120px; left: 20%; }
.hero-content, .hero-visual { position: relative; z-index: 1; }
.hero-content h1, .hero-content p { color: #fff; }
.hero-content p { font-size: 17px; opacity: .9; }
.hero-tags, .floating-tags { display: flex; flex-wrap: wrap; gap: 10px; margin: 22px 0; }
.hero-tags span, .floating-tags span {
    display: inline-flex;
    padding: 7px 12px;
    background: rgba(255,255,255,.15);
    border: 1px solid rgba(255,255,255,.25);
    border-radius: 999px;
    color: #fff;
    font-size: 13px;
    font-weight: 700;
}
.hero-visual {
    margin-top: 32px;
    padding: 18px;
    border-radius: 30px;
    background: rgba(255,255,255,.16);
    border: 1px solid rgba(255,255,255,.28);
    backdrop-filter: blur(8px);
}
.hero-visual img { border-radius: 24px; margin: auto; max-height: 420px; object-fit: contain; }
.status-card {
    margin-top: 14px;
    background: rgba(255,255,255,.94);
    color: #1f2937;
    border-radius: 22px;
    padding: 16px;
    box-shadow: 0 16px 34px rgba(31,41,55,.12);
}
.status-row { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-top: 8px; color: var(--muted); font-size: 14px; }
.status-dot { width: 10px; height: 10px; border-radius: 50%; background: #22c55e; display: inline-block; margin-right: 8px; }
.daily-scenes, .card-grid, .risk-grid, .faq-grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
.scene-card, .info-card, .risk-card, .faq-item, .step-card, .article-panel, .safety-panel, .download-panel {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.05);
}
.scene-card .tag, .bento-card .tag { color: var(--blue); font-size: 13px; font-weight: 800; }
.link-arrow { color: var(--blue); font-weight: 800; display: inline-flex; margin-top: 8px; }
.bento-feature-center { display: grid; grid-template-columns: 1fr; gap: 16px; }
.bento-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 24px;
    min-height: 180px;
    box-shadow: 0 12px 30px rgba(15, 23, 42, 0.05);
}
.bento-card.featured { background: linear-gradient(180deg, #ffffff 0%, #eef5ff 100%); }
.split-section, .safe-browsing-section, .smart-route-section, .multi-device-section, .network-diagnosis-section, .account-security-section {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
    align-items: center;
}
.visual-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 34px;
    padding: 20px;
    box-shadow: var(--shadow);
}
.visual-card.soft { background: linear-gradient(180deg, #f8fbff 0%, #ffffff 100%); }
.visual-card img { max-height: 420px; margin: auto; object-fit: contain; border-radius: 24px; }
.feature-list, .check-list { list-style: none; margin: 18px 0; padding: 0; display: grid; gap: 10px; }
.feature-list li, .check-list li {
    padding: 12px 14px;
    border-radius: 16px;
    background: #f6f9fd;
    color: #374151;
    border: 1px solid #e8eef6;
}
.feature-list li::before, .check-list li::before { content: "✓"; color: var(--blue); font-weight: 900; margin-right: 8px; }
.public-wifi-section, .privacy-guard-section {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 34px;
    padding: 24px;
    box-shadow: var(--shadow);
}
.panel-grid { display: grid; grid-template-columns: 1fr; gap: 14px; margin-top: 18px; }
.panel-card {
    border: 1px solid var(--line);
    background: #f8fafd;
    border-radius: 22px;
    padding: 18px;
}
.process-steps { display: grid; grid-template-columns: 1fr; gap: 14px; counter-reset: steps; }
.step-card { position: relative; overflow: hidden; }
.step-number {
    width: 38px;
    height: 38px;
    display: inline-grid;
    place-items: center;
    border-radius: 14px;
    color: #fff;
    background: var(--blue);
    font-weight: 900;
    margin-bottom: 12px;
}
.risk-card { border-left: 5px solid var(--blue); }
.cta-section { padding: 56px 0 72px; }
.cta-box {
    background: var(--gradient);
    color: #fff;
    border-radius: 34px;
    padding: 34px 22px;
    text-align: center;
    box-shadow: 0 24px 70px rgba(53,88,242,.20);
}
.cta-box h2, .cta-box p { color: #fff; }
.page-hero { padding: 44px 0 24px; }
.page-hero-box {
    background: linear-gradient(180deg, #ffffff 0%, #f0f6ff 100%);
    border: 1px solid var(--line);
    border-radius: 34px;
    padding: 28px;
    box-shadow: var(--shadow);
}
.guide-layout { display: grid; grid-template-columns: 1fr; gap: 22px; align-items: start; }
.article-body { background: #fff; border: 1px solid var(--line); border-radius: 30px; padding: 24px; box-shadow: var(--shadow); }
.article-body h2 { font-size: 26px; margin-top: 28px; }
.side-note { background: #eef5ff; border: 1px solid #d6e7ff; border-radius: 26px; padding: 22px; position: sticky; top: 96px; }
.download-panel { text-align: center; margin-top: 24px; }
.faq-item h3 { display: flex; gap: 10px; }
.faq-item h3::before { content: "Q"; color: var(--blue); font-weight: 900; }
.site-footer { background: #111827; color: #cbd5e1; padding: 46px 0; }
.site-footer p, .site-footer a { color: #cbd5e1; }
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 28px; }
.footer-brand { color: #fff; font-size: 22px; font-weight: 900; margin-bottom: 10px; }
.site-footer h3 { color: #fff; font-size: 16px; }
.site-footer a { display: block; margin: 8px 0; }
.legal-note { font-size: 13px; opacity: .8; }
@media (min-width: 720px) {
    .container { width: min(1120px, calc(100% - 48px)); }
    .daily-scenes, .card-grid { grid-template-columns: repeat(2, 1fr); }
    .risk-grid, .faq-grid { grid-template-columns: repeat(2, 1fr); }
    .panel-grid { grid-template-columns: repeat(3, 1fr); }
    .process-steps { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1.5fr 1fr 1fr; }
}
@media (min-width: 980px) {
    .site-nav { display: flex; position: static; padding: 0; border: 0; box-shadow: none; background: transparent; gap: 2px; align-items: center; }
    .site-nav a { padding: 9px 11px; font-size: 14px; }
    .nav-toggle-label { display: none; }
    .hero-shell { display: grid; grid-template-columns: 1.02fr .98fr; align-items: center; gap: 28px; padding: 58px; }
    .hero-visual { margin-top: 0; }
    .daily-scenes { grid-template-columns: repeat(3, 1fr); }
    .bento-feature-center { grid-template-columns: repeat(6, 1fr); grid-auto-rows: minmax(170px, auto); }
    .bento-card { grid-column: span 2; }
    .bento-card.featured { grid-column: span 3; grid-row: span 2; }
    .bento-card.wide { grid-column: span 4; }
    .safe-browsing-section, .smart-route-section, .multi-device-section, .network-diagnosis-section, .account-security-section, .split-section { grid-template-columns: 1fr 1fr; gap: 36px; }
    .public-wifi-section { padding: 34px; display: grid; grid-template-columns: 1.2fr .8fr; gap: 28px; align-items: center; }
    .privacy-guard-section { padding: 34px; }
    .process-steps { grid-template-columns: repeat(3, 1fr); }
    .risk-grid { grid-template-columns: repeat(3, 1fr); }
    .guide-layout { grid-template-columns: minmax(0, 1fr) 320px; }
    .article-body, .page-hero-box { padding: 34px; }
}
@media (max-width: 420px) {
    .container { width: min(100% - 24px, 1120px); }
    .hero-shell, .cta-box { border-radius: 26px; padding: 28px 18px; }
    .download-btn { width: 100%; }
    .scene-card, .info-card, .risk-card, .faq-item, .step-card, .article-panel, .safety-panel, .download-panel { padding: 18px; border-radius: 22px; }
}