:root {
    --primary: rgb(70,139,223);
    --primary-dark: #225fa8;
    --primary-soft: #eaf4ff;
    --ink: #172033;
    --muted: #657085;
    --line: #dbe7f5;
    --card: rgba(255,255,255,.86);
    --bg: #f6fbff;
    --shadow: 0 18px 45px rgba(50, 105, 174, .12);
    --radius: 22px;
}

* { box-sizing: border-box; }
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(--ink);
    background: linear-gradient(180deg, #f3f9ff 0%, #ffffff 34%, #f7fbff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: min(1120px, calc(100% - 36px)); margin: 0 auto; }
.section { padding: 58px 0; }
.section-tight { padding: 36px 0; }
.section-head { max-width: 760px; margin-bottom: 26px; }
.eyebrow, .badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    border: 1px solid rgba(70,139,223,.22);
    background: rgba(234,244,255,.72);
    color: var(--primary-dark);
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 13px;
    font-weight: 700;
}
h1, h2, h3 { line-height: 1.25; margin: 0 0 14px; color: #101a2c; }
h1 { font-size: clamp(32px, 9vw, 58px); letter-spacing: -1.8px; }
h2 { font-size: clamp(26px, 5.5vw, 40px); letter-spacing: -1px; }
h3 { font-size: 20px; }
p { margin: 0 0 14px; color: var(--muted); }
ul, ol { margin: 0; padding-left: 20px; color: var(--muted); }

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,.88);
    backdrop-filter: blur(18px);
    border-bottom: 1px solid rgba(219,231,245,.78);
}
.nav-shell {
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; color: #10203a; }
.brand-logo { width: 38px; height: 38px; border-radius: 12px; }
.brand-text { white-space: nowrap; letter-spacing: -.2px; }
.site-nav {
    position: absolute;
    top: 70px;
    left: 18px;
    right: 18px;
    display: none;
    flex-direction: column;
    gap: 8px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 14px;
    box-shadow: var(--shadow);
}
.site-nav.open { display: flex; }
.site-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #42506a;
    font-size: 15px;
    font-weight: 650;
}
.site-nav a:hover, .site-nav a.active { background: var(--primary-soft); color: var(--primary-dark); }
.nav-toggle {
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 13px;
    background: #fff;
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
    cursor: pointer;
}
.nav-toggle span { width: 18px; height: 2px; border-radius: 2px; background: var(--ink); }

.hero {
    position: relative;
    padding: 48px 0 34px;
    background:
        radial-gradient(circle at 18% 15%, rgba(70,139,223,.18), transparent 36%),
        radial-gradient(circle at 88% 14%, rgba(70,139,223,.14), transparent 30%),
        linear-gradient(135deg, #f4faff 0%, #ffffff 48%, #eef7ff 100%);
    overflow: hidden;
}
.hero::after {
    content: "";
    position: absolute;
    inset: auto -90px -120px auto;
    width: 320px;
    height: 320px;
    border-radius: 50%;
    background: rgba(70,139,223,.10);
    filter: blur(2px);
}
.hero-layout { position: relative; display: grid; gap: 32px; align-items: center; z-index: 1; }
.hero-copy p { font-size: 17px; max-width: 620px; }
.hero-tags, .tag-row { display: flex; flex-wrap: wrap; gap: 10px; margin: 18px 0 24px; }
.pill {
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    padding: 7px 12px;
    background: #fff;
    border: 1px solid var(--line);
    color: #42506a;
    box-shadow: 0 8px 22px rgba(70,139,223,.08);
    font-size: 13px;
    font-weight: 700;
}
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 22px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    font-size: 16px;
    box-shadow: 0 12px 28px rgba(70,139,223,.30);
    border: 1px solid rgba(70,139,223,.4);
    transition: transform .2s ease, box-shadow .2s ease;
    cursor: pointer;
}
.download-btn:hover { transform: translateY(-2px); box-shadow: 0 16px 36px rgba(70,139,223,.34); }
.hero-visual {
    position: relative;
    min-height: 420px;
    display: grid;
    place-items: center;
}
.product-panel {
    position: relative;
    width: min(100%, 430px);
    border-radius: 32px;
    padding: 22px;
    background: linear-gradient(180deg, rgba(255,255,255,.84), rgba(235,246,255,.82));
    border: 1px solid rgba(255,255,255,.9);
    box-shadow: var(--shadow);
}
.product-panel .app-img { width: min(260px, 76%); margin: 0 auto; filter: drop-shadow(0 20px 28px rgba(38,80,132,.16)); }
.floating-card {
    position: absolute;
    background: rgba(255,255,255,.94);
    border: 1px solid rgba(219,231,245,.95);
    border-radius: 18px;
    padding: 12px 14px;
    box-shadow: 0 18px 38px rgba(40,92,160,.14);
    color: #2b3c59;
}
.status-card { top: 18px; right: 6px; max-width: 174px; }
.status-card strong { display:block; color:#10203a; margin-bottom: 3px; }
.status-card span { font-size: 12px; color: var(--muted); }
.mini-card { font-size: 12px; font-weight: 800; }
.mini-card.one { left: 10px; bottom: 74px; }
.mini-card.two { right: 24px; bottom: 28px; }
.mini-card.three { left: 26px; top: 66px; }

.trust-grid, .category-grid, .feature-grid, .scenario-grid, .article-grid, .info-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}
.trust-item, .category-card, .feature-card, .scenario-card, .info-card, .faq-item, .step, .safe-card, .article-card {
    background: var(--card);
    border: 1px solid rgba(219,231,245,.92);
    border-radius: var(--radius);
    padding: 20px;
    box-shadow: 0 10px 30px rgba(45, 96, 160, .08);
}
.trust-item strong { display: block; color: #12213a; font-size: 18px; margin-bottom: 4px; }
.trust-item span { color: var(--muted); font-size: 14px; }
.category-card { position: relative; overflow: hidden; min-height: 172px; }
.category-card::before {
    content: "";
    position: absolute;
    inset: 0 0 auto auto;
    width: 96px;
    height: 96px;
    background: radial-gradient(circle, rgba(70,139,223,.18), transparent 70%);
}
.category-card p, .feature-card p, .scenario-card p { margin-bottom: 12px; }
.card-link { color: var(--primary-dark); font-weight: 800; font-size: 14px; }

.split-layout, .security-layout, .guide-layout { display: grid; gap: 24px; align-items: start; }
.surface-panel {
    border: 1px solid rgba(219,231,245,.94);
    border-radius: 28px;
    background: linear-gradient(145deg, rgba(255,255,255,.9), rgba(236,247,255,.84));
    box-shadow: var(--shadow);
    padding: 24px;
}
.security-panel {
    display: grid;
    gap: 14px;
}
.security-row {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 12px;
    align-items: start;
    padding: 14px;
    border-radius: 18px;
    background: rgba(255,255,255,.78);
    border: 1px solid rgba(219,231,245,.82);
}
.icon-dot {
    width: 34px;
    height: 34px;
    border-radius: 12px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    display: inline-grid;
    place-items: center;
    font-weight: 900;
}
.steps { display: grid; grid-template-columns: 1fr; gap: 16px; counter-reset: step; }
.step { position: relative; padding-top: 52px; }
.step::before {
    counter-increment: step;
    content: counter(step, decimal-leading-zero);
    position: absolute;
    left: 20px;
    top: 16px;
    width: 34px;
    height: 28px;
    display: grid;
    place-items: center;
    border-radius: 10px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    font-size: 13px;
}
.faq-list { display: grid; gap: 14px; }
.faq-item h3 { font-size: 18px; margin-bottom: 8px; }
.cta-section {
    text-align: center;
    border-radius: 30px;
    padding: 36px 22px;
    background: linear-gradient(135deg, rgba(70,139,223,.10), rgba(255,255,255,.92));
    border: 1px solid rgba(219,231,245,.92);
    box-shadow: var(--shadow);
}
.cta-section p { max-width: 680px; margin-left: auto; margin-right: auto; }
.page-hero {
    padding: 42px 0;
    background: linear-gradient(135deg, #eef7ff 0%, #ffffff 58%, #f6fbff 100%);
    border-bottom: 1px solid rgba(219,231,245,.72);
}
.page-hero p { max-width: 760px; font-size: 17px; }
.breadcrumb { color: var(--primary-dark); font-weight: 800; font-size: 13px; margin-bottom: 12px; }
.note-box {
    border-left: 4px solid var(--primary);
    background: #f3f9ff;
    border-radius: 18px;
    padding: 18px;
    color: #40516c;
}
.check-list { display: grid; gap: 12px; padding: 0; list-style: none; }
.check-list li {
    padding: 12px 14px;
    border-radius: 14px;
    background: rgba(255,255,255,.74);
    border: 1px solid var(--line);
}
.download-single { margin-top: 22px; }

.site-footer {
    margin-top: 38px;
    background: #10203a;
    color: #dce7f5;
    padding: 42px 0 22px;
}
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 24px; }
.footer-grid p { color: #b8c5d7; max-width: 520px; }
.footer-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.footer-brand img { width: 34px; height: 34px; border-radius: 10px; }
.site-footer h3 { color: #fff; font-size: 16px; margin-bottom: 10px; }
.site-footer a { display:block; color: #b8c5d7; margin: 6px 0; font-size: 14px; }
.site-footer a:hover { color: #fff; }
.footer-bottom {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding-top: 22px;
    margin-top: 22px;
    border-top: 1px solid rgba(255,255,255,.1);
    color: #9fb0c6;
    font-size: 13px;
}

@media (min-width: 640px) {
    .category-grid, .trust-grid, .article-grid, .info-grid { grid-template-columns: repeat(2, 1fr); }
    .steps { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
    .container { width: min(1120px, calc(100% - 56px)); }
    .nav-toggle { display: none; }
    .site-nav {
        position: static;
        display: flex;
        flex-direction: row;
        align-items: center;
        gap: 4px;
        border: 0;
        padding: 0;
        box-shadow: none;
        background: transparent;
    }
    .site-nav a { padding: 9px 12px; }
    .hero { padding: 72px 0 54px; }
    .hero-layout { grid-template-columns: 1.08fr .92fr; gap: 56px; }
    .trust-grid { grid-template-columns: repeat(4, 1fr); }
    .category-grid, .feature-grid, .scenario-grid, .article-grid { grid-template-columns: repeat(3, 1fr); }
    .split-layout, .security-layout, .guide-layout { grid-template-columns: 1fr 1fr; gap: 42px; }
    .steps { grid-template-columns: repeat(4, 1fr); }
    .footer-grid { grid-template-columns: 1.7fr .7fr .7fr; }
    .footer-bottom { flex-direction: row; justify-content: space-between; }
}