:root {
    --brand-gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
    --blue: #2980FE;
    --blue-hover: #1768E8;
    --text: #1f2937;
    --muted: #667085;
    --light: #f6f8fc;
    --line: #e6ebf2;
    --white: #ffffff;
    --radius-xl: 36px;
    --radius-lg: 26px;
    --radius-md: 18px;
    --shadow: 0 18px 50px rgba(28, 45, 97, 0.08);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
    color: var(--text);
    background: #f8fafd;
    line-height: 1.72;
    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; }
.section { padding: 58px 0; }
.section-head { max-width: 760px; margin-bottom: 28px; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.section-kicker, .category-badge, .mini-tag, .blue-tag {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--blue);
    background: #eef5ff;
    border: 1px solid #dbeaff;
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 700;
}
h1, h2, h3 { margin: 0 0 14px; line-height: 1.18; color: #172033; }
h1 { font-size: clamp(34px, 7vw, 62px); letter-spacing: -1.8px; }
h2 { font-size: clamp(28px, 4vw, 42px); letter-spacing: -1px; }
h3 { font-size: 21px; }
p { margin: 0 0 16px; color: var(--muted); }
ul, ol { margin: 0; padding-left: 20px; color: var(--muted); }
.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255,255,255,.88);
    border-bottom: 1px solid rgba(230,235,242,.9);
    backdrop-filter: blur(16px);
}
.header-inner { min-height: 74px; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.logo { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; color: #16213a; font-size: 18px; }
.logo img { width: 42px; height: 42px; object-fit: cover; border-radius: 12px; }
.site-nav { display: none; align-items: center; gap: 8px; }
.site-nav a { padding: 10px 12px; color: #4b5565; border-radius: 999px; font-size: 14px; font-weight: 650; }
.site-nav a:hover, .site-nav a.active { color: var(--blue); background: #eef5ff; }
.mobile-nav-toggle { border: 0; border-radius: 999px; background: #eef5ff; color: var(--blue); padding: 9px 14px; font-weight: 800; }
.site-nav.open { display: grid; position: absolute; top: 74px; left: 16px; right: 16px; background: #fff; border: 1px solid var(--line); border-radius: 22px; padding: 12px; box-shadow: var(--shadow); }
.gradient-background { background: var(--brand-gradient); color: #fff; }
.network-manager-hero { padding: 28px 0 42px; }
.hero-panel {
    background: var(--brand-gradient);
    border-radius: var(--radius-xl);
    padding: 30px;
    color: #fff;
    position: relative;
    overflow: hidden;
    box-shadow: 0 24px 70px rgba(53,88,242,.22);
}
.hero-panel:before, .hero-panel:after {
    content: "";
    position: absolute;
    width: 280px;
    height: 280px;
    border-radius: 999px;
    background: rgba(255,255,255,.16);
    filter: blur(4px);
}
.hero-panel:before { right: -90px; top: -120px; }
.hero-panel:after { left: 40%; bottom: -170px; }
.hero-grid { position: relative; z-index: 1; display: grid; gap: 34px; align-items: center; }
.hero-copy p { color: rgba(255,255,255,.86); font-size: 17px; max-width: 640px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin: 20px 0 24px; }
.hero-tags span, .floating-card { background: rgba(255,255,255,.18); border: 1px solid rgba(255,255,255,.28); border-radius: 999px; padding: 8px 13px; color: #fff; font-size: 13px; font-weight: 700; }
.hero-visual { position: relative; min-height: 320px; display: grid; place-items: center; }
.hero-device {
    width: min(360px, 86%);
    border-radius: 32px;
    background: rgba(255,255,255,.14);
    padding: 18px;
    box-shadow: 0 26px 60px rgba(7, 21, 83, .28);
}
.hero-device img { border-radius: 26px; margin: auto; }
.floating-card { position: absolute; background: rgba(255,255,255,.92); color: #1d2b4d; box-shadow: 0 14px 38px rgba(25, 35, 70, .16); }
.float-one { left: 0; top: 30px; }
.float-two { right: 0; top: 68px; }
.float-three { left: 10px; bottom: 56px; }
.float-four { right: 18px; bottom: 16px; }
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 12px 24px;
    border-radius: 999px;
    background: var(--blue);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 30px rgba(41, 128, 254, .25);
    transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}
.download-btn:hover { background: var(--blue-hover); transform: translateY(-1px); box-shadow: 0 18px 36px rgba(23, 104, 232, .28); }
.hero-panel .download-btn { background: #fff; color: var(--blue); }
.hero-panel .download-btn:hover { background: #f4f8ff; color: var(--blue-hover); }
.card-grid, .daily-scenes, .risk-grid, .faq-grid, .info-grid { display: grid; gap: 18px; }
.scene-card, .bento-card, .feature-card, .safety-panel, .risk-card, .faq-item, .step-card, .guide-card, .content-card, .aside-card {
    background: var(--white);
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: 0 12px 36px rgba(40, 55, 90, .05);
}
.scene-card { position: relative; overflow: hidden; }
.scene-card:before, .risk-card:before { content: ""; position: absolute; left: 0; top: 24px; bottom: 24px; width: 4px; background: var(--blue); border-radius: 99px; }
.scene-card a, .bento-card a, .text-link, .content-card a, .aside-card a { color: var(--blue); font-weight: 800; }
.bento-feature-center { display: grid; gap: 18px; }
.bento-card { min-height: 188px; display: flex; flex-direction: column; justify-content: space-between; position: relative; overflow: hidden; }
.bento-card.large { background: linear-gradient(135deg, #ffffff, #f1f6ff); }
.bento-card:after { content: ""; position: absolute; right: -48px; bottom: -48px; width: 120px; height: 120px; border-radius: 999px; background: #eef5ff; }
.split-section, .safe-browsing-section, .smart-route-section, .multi-device-section, .network-diagnosis-section, .account-security-section { display: grid; gap: 24px; align-items: center; }
.media-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius-xl);
    padding: 22px;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}
.media-card.soft { background: linear-gradient(145deg, #ffffff, #eef5ff); }
.media-card img { margin: auto; border-radius: 24px; }
.feature-list { display: grid; gap: 12px; margin: 20px 0; }
.feature-list div, .check-item { background: #f6f8fc; border: 1px solid var(--line); border-radius: 18px; padding: 14px 16px; color: #465166; }
.public-wifi-section, .privacy-guard-section { background: #fff; border-radius: var(--radius-xl); padding: 28px; border: 1px solid var(--line); box-shadow: var(--shadow); }
.wifi-layout, .privacy-layout { display: grid; gap: 22px; align-items: center; }
.tag-row { display: flex; flex-wrap: wrap; gap: 10px; margin: 16px 0; }
.tag-row span { color: #334155; background: #f3f6fb; border: 1px solid var(--line); border-radius: 999px; padding: 6px 12px; font-size: 13px; font-weight: 700; }
.process-steps { display: grid; gap: 16px; counter-reset: step; }
.step-card { position: relative; padding-left: 82px; }
.step-number { position: absolute; left: 24px; top: 24px; width: 38px; height: 38px; border-radius: 14px; display: grid; place-items: center; background: var(--blue); color: #fff; font-weight: 900; }
.risk-grid { grid-template-columns: 1fr; }
.risk-card { position: relative; padding-left: 28px; }
.faq-item summary { cursor: pointer; color: #172033; font-weight: 850; list-style: none; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item p { margin-top: 12px; }
.cta-section { padding: 64px 0; }
.cta-panel { text-align: center; background: var(--brand-gradient); color: #fff; border-radius: var(--radius-xl); padding: 40px 24px; overflow: hidden; position: relative; }
.cta-panel p { color: rgba(255,255,255,.84); max-width: 680px; margin-left: auto; margin-right: auto; }
.page-hero { padding: 46px 0 26px; }
.page-hero-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-xl); padding: 30px; box-shadow: var(--shadow); }
.page-hero p { max-width: 780px; font-size: 17px; }
.page-layout { display: grid; gap: 22px; align-items: start; padding: 26px 0 60px; }
.content-stack { display: grid; gap: 18px; }
.guide-card h2, .content-card h2 { font-size: 26px; }
.inline-list { display: grid; gap: 12px; margin-top: 16px; padding: 0; list-style: none; }
.inline-list li { background: #f6f8fc; border: 1px solid var(--line); border-radius: 18px; padding: 14px 16px; color: var(--muted); }
.download-page .download-btn { margin: 16px 0 8px; }
.install-steps { display: grid; gap: 14px; padding: 0; list-style: none; counter-reset: install; }
.install-steps li { counter-increment: install; background: #f6f8fc; border: 1px solid var(--line); border-radius: 18px; padding: 16px 16px 16px 62px; position: relative; color: var(--muted); }
.install-steps li:before { content: counter(install); position: absolute; left: 16px; top: 16px; width: 30px; height: 30px; border-radius: 12px; background: var(--blue); color: #fff; display: grid; place-items: center; font-weight: 900; }
.site-footer { background: #111827; color: #d7dce8; padding: 44px 0 20px; }
.site-footer p { color: #aab3c3; }
.footer-grid { display: grid; gap: 28px; }
.footer-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.footer-brand img { width: 38px; height: 38px; border-radius: 12px; object-fit: cover; }
.site-footer h3 { color: #fff; font-size: 16px; }
.site-footer a { display: block; color: #aab3c3; margin: 8px 0; }
.site-footer a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.09); margin-top: 26px; padding-top: 18px; color: #8993a4; font-size: 14px; }
@media (min-width: 640px) {
    .daily-scenes, .card-grid, .info-grid, .faq-grid { grid-template-columns: repeat(2, 1fr); }
    .risk-grid { grid-template-columns: repeat(2, 1fr); }
    .process-steps { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
    .mobile-nav-toggle { display: none; }
    .site-nav { display: flex; }
    .hero-panel { padding: 56px; }
    .hero-grid { grid-template-columns: 1.08fr .92fr; }
    .daily-scenes { grid-template-columns: repeat(3, 1fr); }
    .bento-feature-center { grid-template-columns: repeat(6, 1fr); }
    .bento-card { grid-column: span 2; }
    .bento-card.large { grid-column: span 3; min-height: 240px; }
    .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; }
    .wifi-layout, .privacy-layout { grid-template-columns: 1.05fr .95fr; }
    .risk-grid { grid-template-columns: repeat(3, 1fr); }
    .process-steps { grid-template-columns: repeat(3, 1fr); }
    .page-layout { grid-template-columns: minmax(0, 1fr) 320px; }
    .footer-grid { grid-template-columns: 1.4fr .8fr .8fr; }
}
@media (max-width: 420px) {
    .container { width: min(100% - 24px, 1120px); }
    .hero-panel, .page-hero-card, .public-wifi-section, .privacy-guard-section { border-radius: 24px; padding: 24px 18px; }
    .floating-card { position: static; margin: 8px; display: inline-flex; }
    .hero-visual { min-height: auto; display: block; }
    .hero-device { width: 100%; }
    .step-card { padding-left: 24px; padding-top: 72px; }
}