:root {
    --primary: rgb(70,139,223);
    --primary-dark: rgb(42,95,166);
    --primary-soft: rgb(233,244,255);
    --ink: #102033;
    --muted: #5f7086;
    --line: #dbe8f5;
    --card: rgba(255,255,255,.92);
    --shadow: 0 18px 48px rgba(48, 91, 139, .12);
    --radius-lg: 24px;
    --radius-md: 18px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    min-width: 320px;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    color: var(--ink);
    background:
        radial-gradient(circle at 8% 4%, rgba(70,139,223,.18), transparent 28rem),
        linear-gradient(180deg, #f6fbff 0%, #eef6ff 44%, #ffffff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: min(100% - 32px, 1160px); margin-inline: auto; }

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,.86);
    backdrop-filter: blur(18px);
    border-bottom: 1px solid rgba(170,199,230,.55);
}
.nav-wrap { display: flex; align-items: center; justify-content: space-between; min-height: 72px; gap: 16px; }
.brand, .footer-brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; letter-spacing: .02em; }
.logo { width: 38px; height: 38px; border-radius: 12px; box-shadow: 0 10px 24px rgba(70,139,223,.22); }
.brand-text { font-size: 18px; }
.nav-toggle { width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 14px; background: #fff; display: grid; place-content: center; gap: 5px; cursor: pointer; }
.nav-toggle span { width: 18px; height: 2px; background: var(--ink); border-radius: 2px; display: block; }
.site-nav { position: absolute; left: 16px; right: 16px; top: 76px; padding: 12px; display: none; grid-template-columns: 1fr; gap: 6px; border: 1px solid var(--line); background: #fff; border-radius: 18px; box-shadow: var(--shadow); }
.site-nav.is-open { display: grid; }
.site-nav a { padding: 10px 12px; border-radius: 12px; color: #38506b; font-size: 15px; }
.site-nav a.active, .site-nav a:hover { background: var(--primary-soft); color: var(--primary-dark); }

.hero { padding: 48px 0 34px; }
.hero-layout { display: grid; gap: 28px; align-items: center; }
.eyebrow, .badge { display: inline-flex; align-items: center; gap: 8px; width: fit-content; color: var(--primary-dark); background: rgba(70,139,223,.1); border: 1px solid rgba(70,139,223,.22); border-radius: 999px; padding: 7px 12px; font-size: 13px; font-weight: 700; }
.hero h1, .page-hero h1 { margin: 16px 0 14px; font-size: clamp(32px, 8vw, 62px); line-height: 1.12; letter-spacing: -.04em; }
.hero p, .page-hero p { color: var(--muted); font-size: 17px; margin: 0; }
.hero-actions { margin-top: 24px; display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }
.download-btn { display: inline-flex; align-items: center; justify-content: center; min-height: 48px; padding: 0 24px; border-radius: 999px; border: 0; background: var(--primary); color: #fff; font-weight: 800; box-shadow: 0 16px 30px rgba(70,139,223,.28); cursor: pointer; transition: transform .2s ease, box-shadow .2s ease; }
.download-btn:hover { transform: translateY(-2px); box-shadow: 0 20px 36px rgba(70,139,223,.34); }
.safe-note { color: var(--muted); font-size: 14px; }
.hero-tags, .tag-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.tag { padding: 8px 12px; border-radius: 999px; background: #fff; border: 1px solid var(--line); color: #466078; font-size: 13px; box-shadow: 0 10px 26px rgba(72,112,152,.07); }
.product-visual { position: relative; min-height: 430px; display: grid; place-items: center; background: linear-gradient(145deg, rgba(70,139,223,.12), rgba(255,255,255,.86)); border: 1px solid rgba(164,196,230,.65); border-radius: 32px; overflow: hidden; box-shadow: var(--shadow); }
.product-visual:before { content: ""; position: absolute; width: 360px; height: 360px; border-radius: 50%; background: rgba(70,139,223,.13); filter: blur(8px); }
.app-shot { position: relative; z-index: 1; max-width: min(78%, 320px); filter: drop-shadow(0 30px 42px rgba(47,88,132,.2)); }
.status-card { position: absolute; z-index: 2; left: 18px; bottom: 18px; width: min(250px, calc(100% - 36px)); background: rgba(255,255,255,.9); border: 1px solid rgba(202,222,244,.9); border-radius: 20px; padding: 16px; box-shadow: 0 16px 40px rgba(44,87,130,.16); }
.status-card strong { display: block; font-size: 16px; }
.status-card span { color: var(--muted); font-size: 13px; }
.status-dot { width: 10px; height: 10px; border-radius: 50%; background: var(--primary); display: inline-block; margin-right: 7px; }

.section { padding: 44px 0; }
.section-title { margin-bottom: 22px; }
.section-title h2 { margin: 0 0 8px; font-size: clamp(26px, 5vw, 40px); letter-spacing: -.03em; line-height: 1.18; }
.section-title p { margin: 0; color: var(--muted); }
.card { background: var(--card); border: 1px solid rgba(203,222,242,.86); border-radius: var(--radius-lg); padding: 22px; box-shadow: var(--shadow); }
.feature-grid, .category-grid, .scenario-grid, .faq-grid, .content-grid, .trust-grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
.feature-card h3, .category-card h3, .scenario-card h3, .faq-item h2, .faq-item h3, .content-card h2, .content-card h3 { margin: 0 0 8px; line-height: 1.35; }
.feature-card p, .category-card p, .scenario-card p, .faq-item p, .content-card p, .trust-card p { margin: 0; color: var(--muted); }
.card-link { display: inline-flex; margin-top: 14px; color: var(--primary-dark); font-weight: 800; }
.trust-card { padding: 20px; background: #fff; border-radius: 20px; border: 1px solid var(--line); }
.trust-card strong { display: block; font-size: 18px; margin-bottom: 4px; }
.security-panel { display: grid; gap: 18px; align-items: center; background: linear-gradient(135deg, #fff, #edf6ff); }
.security-list { display: grid; gap: 12px; margin: 0; padding: 0; list-style: none; }
.security-list li { padding: 14px 16px; border-radius: 16px; background: rgba(255,255,255,.78); border: 1px solid var(--line); }
.steps { display: grid; grid-template-columns: 1fr; gap: 14px; counter-reset: step; }
.step { position: relative; padding: 22px; border-radius: var(--radius-md); background: #fff; border: 1px solid var(--line); box-shadow: 0 14px 34px rgba(68,100,130,.08); }
.step:before { counter-increment: step; content: counter(step); width: 34px; height: 34px; border-radius: 50%; background: var(--primary); color: #fff; display: grid; place-items: center; font-weight: 900; margin-bottom: 12px; }
.cta-section { text-align: center; padding: 34px 22px; border-radius: 30px; background: linear-gradient(135deg, rgba(70,139,223,.14), rgba(255,255,255,.94)); border: 1px solid rgba(166,201,235,.72); box-shadow: var(--shadow); }
.cta-section h2 { margin: 0 0 10px; font-size: clamp(26px, 5vw, 40px); }
.cta-section p { margin: 0 auto 20px; color: var(--muted); max-width: 720px; }
.page-hero { padding: 44px 0 26px; }
.page-hero-inner { padding: 28px; border-radius: 30px; background: linear-gradient(135deg, rgba(70,139,223,.14), rgba(255,255,255,.94)); border: 1px solid rgba(166,201,235,.72); }
.article-layout { display: grid; gap: 18px; }
.article-body { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 24px; box-shadow: var(--shadow); }
.article-body h2 { margin-top: 0; }
.article-body p { color: #4b6178; }
.info-panel { background: #f4f9ff; border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 22px; }
.info-panel ul, .article-body ul, .article-body ol { margin: 10px 0 0; padding-left: 20px; color: #4b6178; }
.faq-item { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-md); padding: 20px; }
.only-download { display: flex; justify-content: center; margin-top: 22px; }

.site-footer { margin-top: 40px; padding: 40px 0 24px; background: #102033; color: rgba(255,255,255,.8); }
.footer-grid { display: grid; gap: 24px; }
.footer-brand { color: #fff; margin-bottom: 12px; }
.footer-brand img { width: 34px; height: 34px; border-radius: 11px; }
.site-footer h2 { color: #fff; font-size: 16px; margin: 0 0 10px; }
.site-footer p { margin: 0; max-width: 440px; }
.site-footer a:not(.footer-brand) { display: block; margin: 7px 0; color: rgba(255,255,255,.72); }
.footer-bottom { margin-top: 26px; padding-top: 18px; border-top: 1px solid rgba(255,255,255,.12); display: grid; gap: 8px; font-size: 13px; color: rgba(255,255,255,.64); }

@media (min-width: 640px) {
    .container { width: min(100% - 48px, 1160px); }
    .category-grid, .feature-grid, .scenario-grid, .trust-grid { grid-template-columns: repeat(2, 1fr); }
    .faq-grid, .content-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 900px) {
    .nav-toggle { display: none; }
    .site-nav { position: static; display: flex; align-items: center; gap: 4px; padding: 0; border: 0; box-shadow: none; background: transparent; }
    .site-nav a { padding: 9px 12px; }
    .hero { padding: 76px 0 54px; }
    .hero-layout, .security-panel, .article-layout { grid-template-columns: minmax(0, 1.02fr) minmax(340px, .98fr); }
    .feature-grid, .category-grid, .scenario-grid { grid-template-columns: repeat(3, 1fr); }
    .trust-grid { grid-template-columns: repeat(4, 1fr); }
    .steps { grid-template-columns: repeat(4, 1fr); }
    .footer-grid { grid-template-columns: 1.4fr .8fr .8fr; }
    .footer-bottom { grid-template-columns: 1fr auto; }
}

@media (min-width: 1100px) {
    .product-visual { min-height: 500px; }
    .section { padding: 58px 0; }
    .article-body { padding: 32px; }
}