:root {
    --primary: rgb(70,139,223);
    --primary-dark: #1f5fae;
    --primary-soft: #eaf4ff;
    --ink: #142238;
    --muted: #63748c;
    --line: rgba(70,139,223,.18);
    --card: rgba(255,255,255,.92);
    --shadow: 0 16px 38px rgba(35, 88, 157, .10);
    --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:
        radial-gradient(circle at 14% 4%, rgba(70,139,223,.20), transparent 28%),
        linear-gradient(180deg, #eef7ff 0%, #ffffff 38%, #f7fbff 100%);
    line-height: 1.72;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    backdrop-filter: blur(18px);
    background: rgba(248, 252, 255, .86);
    border-bottom: 1px solid rgba(70,139,223,.12);
}
.header-inner {
    width: min(100%, 720px);
    margin: 0 auto;
    padding: 12px 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}
.logo { width: 34px; height: 34px; border-radius: 12px; box-shadow: 0 8px 18px rgba(70,139,223,.18); }
.brand { display: inline-flex; align-items: center; gap: 9px; font-weight: 800; letter-spacing: .2px; white-space: nowrap; }
.mobile-nav { display: flex; align-items: center; gap: 10px; font-size: 13px; color: #41556f; }
.mobile-nav a { padding: 6px 2px; }
.site-main { width: min(100%, 720px); margin: 0 auto; padding: 18px 16px 34px; }
.gradient-bg { position: relative; overflow: hidden; }
.gradient-bg::before {
    content: "";
    position: absolute;
    inset: -80px -60px auto auto;
    width: 200px;
    height: 200px;
    border-radius: 999px;
    background: rgba(70,139,223,.12);
    filter: blur(8px);
    pointer-events: none;
}
.banner {
    display: grid;
    gap: 20px;
    padding: 24px 18px;
    border: 1px solid rgba(70,139,223,.16);
    border-radius: 28px;
    background:
        linear-gradient(142deg, rgba(255,255,255,.95), rgba(232,244,255,.86)),
        radial-gradient(circle at right top, rgba(70,139,223,.24), transparent 35%);
    box-shadow: var(--shadow);
}
.banner h1, .page-hero h1 { margin: 0; font-size: 29px; line-height: 1.18; letter-spacing: -.8px; }
.banner p, .page-hero p { margin: 10px 0 0; color: var(--muted); font-size: 15px; }
.badges { display: flex; flex-wrap: wrap; gap: 8px; margin: 16px 0; }
.badge { display: inline-flex; align-items: center; border: 1px solid rgba(70,139,223,.18); background: rgba(255,255,255,.76); color: var(--primary-dark); border-radius: 999px; padding: 6px 10px; font-size: 12px; font-weight: 700; }
.hero-device { padding: 12px; border-radius: 25px; background: linear-gradient(180deg, rgba(255,255,255,.8), rgba(234,244,255,.9)); border: 1px solid rgba(70,139,223,.14); }
.app-image { width: 82%; margin: 0 auto; filter: drop-shadow(0 20px 30px rgba(50, 100, 160, .17)); }
.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;
    letter-spacing: .4px;
    box-shadow: 0 12px 24px rgba(70,139,223,.28);
    border: none;
}
.download-btn:active { transform: translateY(1px); }
.section { margin-top: 24px; }
.section h2 { margin: 0 0 12px; font-size: 22px; line-height: 1.3; letter-spacing: -.3px; }
.section p { margin: 0 0 12px; color: var(--muted); font-size: 15px; }
.card {
    border: 1px solid rgba(70,139,223,.14);
    background: var(--card);
    border-radius: var(--radius);
    padding: 18px;
    box-shadow: 0 10px 24px rgba(35, 88, 157, .07);
}
.card + .card { margin-top: 12px; }
.card h3 { margin: 0 0 8px; font-size: 17px; }
.card p, .card li { color: var(--muted); font-size: 14px; }
.feature-grid { display: grid; grid-template-columns: 1fr; gap: 12px; }
.feature-card {
    padding: 16px;
    border-radius: 20px;
    background: linear-gradient(180deg, #fff, #f1f8ff);
    border: 1px solid rgba(70,139,223,.14);
}
.feature-card span.icon {
    display: inline-flex;
    width: 34px;
    height: 34px;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    background: rgba(70,139,223,.11);
    color: var(--primary-dark);
    font-weight: 900;
    margin-bottom: 8px;
}
.stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin-top: 14px; }
.stat { background: rgba(70,139,223,.08); border: 1px solid rgba(70,139,223,.12); border-radius: 18px; padding: 12px 10px; text-align: center; }
.stat strong { display: block; font-size: 18px; color: var(--primary-dark); }
.stat span { font-size: 11px; color: var(--muted); }
.page-hero {
    padding: 24px 18px;
    border-radius: 28px;
    background: linear-gradient(145deg, rgba(255,255,255,.94), rgba(232,244,255,.82));
    border: 1px solid rgba(70,139,223,.16);
    box-shadow: var(--shadow);
}
.steps { counter-reset: step; padding: 0; margin: 14px 0 0; list-style: none; }
.steps li {
    counter-increment: step;
    position: relative;
    padding: 14px 14px 14px 52px;
    margin-bottom: 10px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid rgba(70,139,223,.13);
    color: var(--muted);
}
.steps li::before {
    content: counter(step);
    position: absolute;
    left: 14px;
    top: 14px;
    width: 26px;
    height: 26px;
    border-radius: 10px;
    background: var(--primary);
    color: #fff;
    display: grid;
    place-items: center;
    font-weight: 800;
    font-size: 13px;
}
.faq-item {
    padding: 16px;
    border-radius: 20px;
    background: #fff;
    border: 1px solid rgba(70,139,223,.14);
    box-shadow: 0 8px 20px rgba(35,88,157,.06);
}
.faq-item + .faq-item { margin-top: 12px; }
.faq-item h2, .faq-item h3 { margin: 0 0 8px; font-size: 16px; }
.faq-item p { margin: 0; color: var(--muted); font-size: 14px; }
.note {
    border-radius: 20px;
    padding: 16px;
    background: rgba(70,139,223,.09);
    border: 1px solid rgba(70,139,223,.16);
    color: #344b66;
}
.note strong { color: var(--primary-dark); }
.cta-panel {
    margin-top: 24px;
    padding: 20px;
    border-radius: 24px;
    background: linear-gradient(135deg, var(--primary), #6db5f4);
    color: #fff;
    box-shadow: 0 18px 34px rgba(70,139,223,.22);
}
.cta-panel p { color: rgba(255,255,255,.88); }
.cta-panel .download-btn { background: #fff; color: var(--primary-dark); box-shadow: none; }
.site-footer { width: min(100%, 720px); margin: 0 auto; padding: 0 16px 28px; }
.footer-card { border-radius: 24px; border: 1px solid rgba(70,139,223,.14); background: rgba(255,255,255,.82); padding: 18px; }
.footer-card p, .copyright { color: var(--muted); font-size: 13px; }
.footer-links { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; margin-top: 12px; font-size: 13px; color: var(--primary-dark); }
.copyright { text-align: center; margin: 16px 0 0; }
.desktop-gate { display: none; }
.desktop-gate-logo { width: 48px; height: 48px; border-radius: 16px; margin: 0 auto 12px; }
@media (min-width: 520px) {
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
    .banner { grid-template-columns: 1.05fr .95fr; align-items: center; }
}
@media (min-width: 769px) {
    body.is-desktop { background: linear-gradient(180deg, #edf6ff, #fff); }
    body.is-desktop .desktop-gate {
        display: flex;
        min-height: 100vh;
        align-items: center;
        justify-content: center;
        padding: 24px;
    }
    .desktop-gate-panel {
        width: min(420px, 94vw);
        text-align: center;
        padding: 28px;
        border-radius: 26px;
        background: rgba(255,255,255,.92);
        border: 1px solid rgba(70,139,223,.16);
        box-shadow: var(--shadow);
    }
    .desktop-gate-panel strong { display: block; font-size: 22px; color: var(--ink); }
    .desktop-gate-panel p { color: var(--muted); font-size: 14px; }
    body.is-desktop .site-header,
    body.is-desktop .site-main,
    body.is-desktop .site-footer {
        position: absolute;
        left: -9999px;
        width: 1px;
        height: 1px;
        overflow: hidden;
    }
    body.is-desktop .download-btn { display: none !important; }
}