:root {
    --primary: rgb(70,139,223);
    --primary-dark: rgb(38,92,165);
    --primary-soft: rgba(70,139,223,0.12);
    --text: #172235;
    --muted: #66748a;
    --line: #dce8f6;
    --card: rgba(255,255,255,0.92);
    --bg: #f7fbff;
    --shadow: 0 18px 50px rgba(28, 80, 140, 0.09);
    --radius: 22px;
}

* { 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;
    color: var(--text);
    background:
        radial-gradient(circle at top left, rgba(70,139,223,0.14), transparent 34rem),
        linear-gradient(180deg, #ffffff 0%, #f4f9ff 45%, #ffffff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255,255,255,0.88);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(220,232,246,0.75);
}
.header-inner, .footer-inner, .container {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
}
.header-inner {
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}
.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: #0d2138;
}
.logo-img {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    object-fit: contain;
}
.nav-toggle {
    border: 1px solid var(--line);
    color: var(--primary-dark);
    background: #fff;
    border-radius: 999px;
    padding: 8px 14px;
    font-size: 14px;
}
.site-nav {
    display: none;
    position: absolute;
    top: 70px;
    left: 16px;
    right: 16px;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: rgba(255,255,255,0.98);
    box-shadow: var(--shadow);
}
.site-nav.open { display: grid; gap: 6px; }
.site-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #40516a;
    font-size: 14px;
}
.site-nav a.active,
.site-nav a:hover {
    color: var(--primary-dark);
    background: var(--primary-soft);
}

.section { padding: 58px 0; }
.section-tight { padding: 36px 0; }
.section-title {
    margin: 0 0 12px;
    font-size: clamp(28px, 4vw, 46px);
    line-height: 1.15;
    letter-spacing: -0.04em;
}
.section-desc {
    margin: 0;
    color: var(--muted);
    max-width: 760px;
}
.center { text-align: center; }
.center .section-desc { margin-left: auto; margin-right: auto; }
.badge-row { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; margin-top: 18px; }
.badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 7px 12px;
    border-radius: 999px;
    color: var(--primary-dark);
    background: rgba(70,139,223,0.10);
    border: 1px solid rgba(70,139,223,0.16);
    font-size: 13px;
    font-weight: 650;
}
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 12px 22px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(70,139,223,0.24);
    transition: transform .2s ease, box-shadow .2s ease;
}
.download-btn:hover { transform: translateY(-2px); box-shadow: 0 18px 34px rgba(70,139,223,0.28); }

.hero {
    padding: 70px 0 42px;
}
.hero-grid {
    display: grid;
    gap: 34px;
    align-items: center;
}
.hero-copy { text-align: center; }
.hero h1 {
    margin: 0;
    font-size: clamp(36px, 8vw, 68px);
    line-height: 1.05;
    letter-spacing: -0.06em;
}
.hero p {
    color: var(--muted);
    margin: 18px auto 24px;
    max-width: 760px;
}
.hero-visual {
    position: relative;
    min-height: 360px;
    padding: 24px;
    border: 1px solid var(--line);
    border-radius: 30px;
    background: linear-gradient(145deg, rgba(255,255,255,0.96), rgba(238,247,255,0.86));
    box-shadow: var(--shadow);
    overflow: hidden;
}
.app-card {
    width: min(280px, 72vw);
    margin: 0 auto;
    padding: 16px;
    border-radius: 30px;
    background: #fff;
    border: 1px solid rgba(70,139,223,0.14);
    box-shadow: 0 18px 50px rgba(28,80,140,0.13);
}
.status-card {
    margin-top: 12px;
    padding: 14px;
    border-radius: 18px;
    background: rgba(255,255,255,0.88);
    border: 1px solid rgba(70,139,223,0.14);
    box-shadow: 0 12px 32px rgba(28,80,140,0.08);
}
.status-card strong { display: block; color: var(--primary-dark); }
.status-card span { color: var(--muted); font-size: 13px; }

.card, .faq-item, .doc-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}
.card { padding: 22px; }
.card h3, .doc-card h3 { margin: 0 0 8px; font-size: 20px; }
.card p, .doc-card p { margin: 0; color: var(--muted); }
.grid { display: grid; gap: 16px; }
.feature-grid { grid-template-columns: 1fr; }
.card-link { display: inline-flex; margin-top: 14px; color: var(--primary-dark); font-weight: 800; }

.banner {
    padding: 54px 0;
    background: linear-gradient(135deg, rgba(70,139,223,0.13), rgba(255,255,255,0.8));
    border-bottom: 1px solid rgba(220,232,246,0.7);
}
.banner h1 {
    margin: 0 0 12px;
    font-size: clamp(32px, 6vw, 58px);
    line-height: 1.12;
    letter-spacing: -0.05em;
}
.banner p { margin: 0; color: var(--muted); max-width: 760px; }

.split-layout {
    display: grid;
    gap: 22px;
    align-items: start;
}
.security-panel {
    padding: 24px;
    border-radius: 26px;
    border: 1px solid rgba(70,139,223,0.16);
    background: linear-gradient(160deg, #fff, #eff7ff);
}
.check-list { margin: 14px 0 0; padding: 0; list-style: none; display: grid; gap: 10px; }
.check-list li {
    padding: 12px 14px;
    border-radius: 15px;
    background: #fff;
    border: 1px solid var(--line);
    color: #40516a;
}
.roadmap {
    display: grid;
    gap: 14px;
    counter-reset: step;
}
.step {
    position: relative;
    padding: 18px 18px 18px 58px;
    border-radius: 20px;
    border: 1px solid var(--line);
    background: #fff;
}
.step::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 18px;
    top: 18px;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    color: #fff;
    font-weight: 800;
    background: var(--primary);
}
.step h3 { margin: 0 0 4px; font-size: 18px; }
.step p { margin: 0; color: var(--muted); font-size: 14px; }

.cta-section {
    padding: 42px 24px;
    border-radius: 30px;
    text-align: center;
    border: 1px solid rgba(70,139,223,0.14);
    background: linear-gradient(135deg, rgba(70,139,223,0.12), rgba(255,255,255,0.96));
    box-shadow: var(--shadow);
}
.cta-section p { color: var(--muted); max-width: 660px; margin: 0 auto 20px; }

.faq-list { display: grid; gap: 14px; }
.faq-item { padding: 20px; }
.faq-item h3 { margin: 0 0 8px; font-size: 18px; }
.faq-item p { margin: 0; color: var(--muted); }

.doc-layout {
    display: grid;
    gap: 22px;
    align-items: start;
}
.article {
    background: rgba(255,255,255,0.88);
    border: 1px solid var(--line);
    border-radius: 28px;
    box-shadow: var(--shadow);
    padding: 24px;
}
.article p { color: #4d5c72; }
.article .download-btn { margin-top: 12px; }
.doc-card { padding: 20px; }
.note {
    padding: 16px;
    border-radius: 18px;
    background: rgba(70,139,223,0.10);
    border: 1px solid rgba(70,139,223,0.18);
    color: #39516d;
}

.site-footer {
    margin-top: 50px;
    padding: 40px 0;
    border-top: 1px solid var(--line);
    background: rgba(255,255,255,0.76);
}
.footer-inner {
    display: grid;
    gap: 24px;
    color: var(--muted);
}
.footer-brand { color: var(--text); }
.footer-links { display: flex; flex-wrap: wrap; gap: 10px; }
.footer-links a {
    padding: 9px 12px;
    border-radius: 999px;
    background: rgba(70,139,223,0.09);
    color: var(--primary-dark);
    font-weight: 650;
}

@media (min-width: 720px) {
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
    .roadmap { grid-template-columns: repeat(2, 1fr); }
    .doc-layout { grid-template-columns: minmax(0, 1fr) 280px; }
    .article { padding: 34px; }
}

@media (min-width: 980px) {
    .nav-toggle { display: none; }
    .site-nav {
        position: static;
        display: flex;
        align-items: center;
        gap: 4px;
        padding: 0;
        border: 0;
        border-radius: 0;
        box-shadow: none;
        background: transparent;
    }
    .hero { padding-top: 90px; }
    .hero-grid { grid-template-columns: 1.03fr .97fr; }
    .hero-copy { text-align: left; }
    .hero p { margin-left: 0; }
    .hero .badge-row { justify-content: flex-start; }
    .feature-grid { grid-template-columns: repeat(3, 1fr); }
    .feature-grid .wide { grid-column: span 2; }
    .split-layout { grid-template-columns: 1fr .9fr; }
    .roadmap { grid-template-columns: repeat(4, 1fr); }
    .status-card.float-a { position: absolute; left: 28px; top: 40px; width: 190px; margin: 0; }
    .status-card.float-b { position: absolute; right: 30px; top: 84px; width: 200px; margin: 0; }
    .status-card.float-c { position: absolute; left: 56px; bottom: 42px; width: 210px; margin: 0; }
    .footer-inner { grid-template-columns: 1fr auto; align-items: center; }
}