:root {
    --primary: rgb(70,139,223);
    --primary-dark: #255fba;
    --primary-soft: #eaf4ff;
    --ink: #102033;
    --muted: #627089;
    --line: #dbe8f7;
    --card: rgba(255,255,255,0.88);
    --shadow: 0 18px 45px rgba(28, 83, 150, 0.12);
    --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(--ink);
    background: linear-gradient(180deg, #f4f9ff 0%, #ffffff 42%, #f6fbff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
p { margin: 0 0 14px; color: var(--muted); }
h1, h2, h3 { margin: 0; line-height: 1.25; color: var(--ink); }
h1 { font-size: clamp(32px, 8vw, 58px); letter-spacing: -1px; }
h2 { font-size: clamp(24px, 5vw, 38px); }
h3 { font-size: 19px; }

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(246, 251, 255, 0.92);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(219,232,247,0.8);
}
.header-inner {
    width: min(1160px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; color: #17375e; }
.logo { width: 38px; height: 38px; border-radius: 12px; }
.nav-toggle {
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 14px;
    width: 42px;
    height: 42px;
    font-size: 22px;
    color: var(--primary-dark);
}
.site-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    display: none;
    flex-direction: column;
    padding: 12px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: var(--shadow);
}
.site-nav.open { display: flex; }
.site-nav a { padding: 10px 12px; border-radius: 12px; color: #52657d; font-size: 15px; }
.site-nav a.active, .site-nav a:hover { background: var(--primary-soft); color: var(--primary-dark); }

.container { width: min(1160px, calc(100% - 32px)); margin: 0 auto; }
.section { padding: 58px 0; }
.section-title { max-width: 760px; margin-bottom: 28px; }
.section-title .eyebrow, .eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 12px;
    border-radius: 999px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-size: 13px;
    font-weight: 700;
    margin-bottom: 14px;
}
.lead { font-size: 17px; color: #52657d; }
.gradient-bg {
    background:
        radial-gradient(circle at 12% 16%, rgba(70,139,223,0.20), transparent 32%),
        radial-gradient(circle at 92% 0%, rgba(153,199,255,0.28), transparent 34%),
        linear-gradient(135deg, #f8fbff 0%, #eef7ff 100%);
}

.hero { padding: 42px 0 70px; }
.hero-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
    align-items: center;
}
.hero-copy { padding-top: 18px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin: 20px 0 26px; }
.tag, .pill {
    display: inline-flex;
    align-items: center;
    border: 1px solid rgba(70,139,223,0.18);
    background: rgba(255,255,255,0.72);
    color: #315f95;
    border-radius: 999px;
    padding: 8px 12px;
    font-size: 13px;
    font-weight: 700;
}
.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    border: none;
    box-shadow: 0 14px 30px rgba(70,139,223,0.28);
    transition: transform .2s ease, box-shadow .2s ease;
    cursor: pointer;
}
.download-btn:hover { transform: translateY(-2px); box-shadow: 0 18px 36px rgba(70,139,223,0.34); }
.hero-device {
    position: relative;
    min-height: 460px;
    border-radius: 32px;
    padding: 24px;
    background: linear-gradient(145deg, rgba(255,255,255,0.72), rgba(237,247,255,0.84));
    border: 1px solid rgba(219,232,247,0.9);
    box-shadow: var(--shadow);
    overflow: hidden;
}
.hero-device:before {
    content: "";
    position: absolute;
    width: 260px;
    height: 260px;
    right: -80px;
    top: -70px;
    background: rgba(70,139,223,0.18);
    border-radius: 50%;
}
.app-shot { width: min(280px, 74%); margin: 20px auto 0; position: relative; z-index: 2; filter: drop-shadow(0 20px 28px rgba(32,81,142,0.18)); }
.status-card, .float-card {
    position: relative;
    z-index: 3;
    background: rgba(255,255,255,0.94);
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: 0 14px 30px rgba(28,83,150,0.10);
    padding: 14px;
}
.status-card { max-width: 260px; margin-left: auto; }
.status-dot { width: 10px; height: 10px; border-radius: 50%; background: var(--primary); display: inline-block; margin-right: 8px; }
.float-stack { display: grid; gap: 10px; margin-top: 16px; }
.float-card { font-size: 13px; font-weight: 700; color: #375b84; }

.trust-grid, .feature-grid, .category-grid, .scenario-grid, .guide-grid, .faq-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}
.trust-item, .feature-card, .category-card, .scenario-card, .guide-card, .faq-item, .notice-card, .info-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 10px 26px rgba(28,83,150,0.07);
}
.trust-item strong { display: block; font-size: 20px; margin-bottom: 6px; color: #17375e; }
.category-card { transition: transform .2s ease, border-color .2s ease; }
.category-card:hover { transform: translateY(-3px); border-color: rgba(70,139,223,0.45); }
.category-card h3, .feature-card h3, .scenario-card h3 { margin-bottom: 10px; }
.card-link { display: inline-flex; margin-top: 12px; color: var(--primary-dark); font-weight: 800; }
.icon-box {
    width: 42px;
    height: 42px;
    border-radius: 14px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
    margin-bottom: 14px;
}

.split-layout, .security-layout, .content-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
    align-items: center;
}
.security-panel {
    background: linear-gradient(145deg, #ffffff, #eef7ff);
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 24px;
    box-shadow: var(--shadow);
}
.security-list, .check-list { list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 12px; }
.security-list li, .check-list li { position: relative; padding-left: 28px; color: #52657d; }
.security-list li:before, .check-list li:before {
    content: "✓";
    position: absolute;
    left: 0;
    top: 0;
    color: var(--primary);
    font-weight: 900;
}
.steps { display: grid; grid-template-columns: 1fr; gap: 14px; counter-reset: step; }
.step {
    position: relative;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 20px;
    padding: 22px;
    box-shadow: 0 10px 22px rgba(28,83,150,0.06);
}
.step:before {
    counter-increment: step;
    content: counter(step);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 12px;
    background: var(--primary);
    color: #fff;
    font-weight: 900;
    margin-bottom: 12px;
}
.cta-section {
    text-align: center;
    background: linear-gradient(135deg, #eaf4ff 0%, #ffffff 100%);
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 34px 22px;
    box-shadow: var(--shadow);
}
.cta-section p { max-width: 720px; margin: 12px auto 22px; }

.page-hero { padding: 54px 0 34px; }
.page-card {
    background: rgba(255,255,255,0.86);
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 28px;
    box-shadow: var(--shadow);
}
.article-content { max-width: 780px; }
.article-content h2 { margin-top: 26px; margin-bottom: 10px; font-size: 26px; }
.article-content p { margin-bottom: 16px; }
.notice-card { background: linear-gradient(145deg, #fff, #f1f8ff); }
.faq-item h3 { margin-bottom: 8px; }
.inline-links { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.inline-links a { color: var(--primary-dark); background: var(--primary-soft); padding: 8px 12px; border-radius: 999px; font-weight: 700; font-size: 14px; }

.download-panel {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
    align-items: center;
}
.safe-note {
    border-left: 4px solid var(--primary);
    padding: 16px 18px;
    background: #f6fbff;
    border-radius: 16px;
    color: #52657d;
}

.site-footer {
    margin-top: 40px;
    background: #f2f8ff;
    border-top: 1px solid var(--line);
    padding: 44px 0 0;
}
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 24px; }
.footer-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.footer-brand img { width: 36px; height: 36px; border-radius: 12px; }
.site-footer h3 { font-size: 16px; margin-bottom: 12px; }
.site-footer a { display: block; color: #52657d; margin: 8px 0; }
.footer-bottom { margin-top: 28px; padding: 18px; text-align: center; color: #6d7b91; border-top: 1px solid var(--line); font-size: 14px; }

@media (min-width: 640px) {
    .trust-grid, .category-grid, .guide-grid { grid-template-columns: repeat(2, 1fr); }
    .steps { grid-template-columns: repeat(2, 1fr); }
    .download-panel { grid-template-columns: 1.1fr .9fr; }
}

@media (min-width: 900px) {
    .nav-toggle { display: none; }
    .site-nav {
        position: static;
        display: flex;
        flex-direction: row;
        padding: 0;
        background: transparent;
        border: none;
        box-shadow: none;
        gap: 4px;
    }
    .hero { padding: 72px 0 86px; }
    .hero-layout { grid-template-columns: 1.02fr .98fr; gap: 52px; }
    .hero-device { min-height: 540px; }
    .float-stack { position: absolute; left: 24px; bottom: 24px; width: 220px; }
    .trust-grid { grid-template-columns: repeat(4, 1fr); }
    .category-grid, .feature-grid, .scenario-grid, .guide-grid, .faq-grid { grid-template-columns: repeat(3, 1fr); }
    .split-layout, .security-layout, .content-layout { grid-template-columns: 1fr 1fr; gap: 44px; }
    .steps { grid-template-columns: repeat(4, 1fr); }
    .footer-grid { grid-template-columns: 1.5fr 1fr 1fr; }
    .page-card { padding: 42px; }
}