/* Mobile first responsive system */
:root {
    --primary: rgb(70,139,223);
    --primary-dark: #245fba;
    --primary-soft: #edf6ff;
    --ink: #102033;
    --muted: #637083;
    --line: #dce8f7;
    --card: rgba(255, 255, 255, 0.92);
    --bg: #f6fbff;
    --radius: 22px;
    --shadow: 0 18px 45px rgba(42, 93, 156, 0.12);
}
* { 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, #eef7ff 0%, #ffffff 38%, #f6fbff 100%);
    line-height: 1.7;
    overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
.container { width: min(100% - 32px, 1180px); margin: 0 auto; }
.section { padding: 58px 0; }
.section-head { max-width: 760px; margin-bottom: 28px; }
.section-kicker,
.eyebrow,
.page-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 12px;
    border: 1px solid rgba(70,139,223,0.18);
    background: rgba(70,139,223,0.08);
    color: var(--primary-dark);
    border-radius: 999px;
    font-size: 13px;
    font-weight: 700;
}
h1, h2, h3 { margin: 0 0 14px; line-height: 1.25; letter-spacing: -0.02em; }
h1 { font-size: clamp(34px, 8vw, 64px); }
h2 { font-size: clamp(26px, 5vw, 42px); }
h3 { font-size: 20px; }
p { margin: 0 0 14px; color: var(--muted); }

/* header, logo, responsive nav, mobile nav, desktop nav */
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,0.9);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(220,232,247,0.85);
}
.header-inner {
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #102033;
    white-space: nowrap;
}
.logo { width: 36px; height: 36px; border-radius: 12px; }
.nav-toggle {
    width: 44px;
    height: 44px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: #fff;
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    cursor: pointer;
}
.nav-toggle span { width: 20px; height: 2px; background: var(--ink); border-radius: 999px; }
.primary-nav {
    position: absolute;
    top: 70px;
    left: 16px;
    right: 16px;
    display: none;
    padding: 14px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 20px;
    box-shadow: var(--shadow);
}
.primary-nav.open { display: grid; gap: 8px; }
.primary-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #34465c;
    font-weight: 650;
}
.primary-nav a.active,
.primary-nav a:hover { color: var(--primary-dark); background: var(--primary-soft); }

/* hero banner and gradient background */
.hero {
    position: relative;
    padding: 54px 0 46px;
    background:
      radial-gradient(circle at 10% 10%, rgba(70,139,223,0.20), transparent 28%),
      radial-gradient(circle at 92% 18%, rgba(120,180,255,0.18), transparent 25%);
}
.hero-layout {
    display: grid;
    gap: 34px;
    align-items: center;
}
.hero-copy { max-width: 680px; }
.hero-copy .lead { font-size: 18px; color: #42556d; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; margin-top: 24px; }
.security-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 22px; }
.security-tags span,
.mini-tag {
    display: inline-flex;
    padding: 8px 12px;
    border-radius: 999px;
    background: #fff;
    border: 1px solid var(--line);
    color: #2d4a68;
    font-size: 13px;
    box-shadow: 0 8px 22px rgba(70,139,223,0.08);
}
.hero-visual { position: relative; min-height: 430px; }
.product-card {
    position: relative;
    width: min(100%, 420px);
    margin: 0 auto;
    padding: 24px;
    border-radius: 32px;
    background: linear-gradient(145deg, rgba(255,255,255,0.96), rgba(239,247,255,0.92));
    border: 1px solid rgba(255,255,255,0.8);
    box-shadow: var(--shadow);
}
.product-card img { margin: 0 auto; border-radius: 28px; max-height: 420px; object-fit: contain; }
.float-card {
    position: absolute;
    background: rgba(255,255,255,0.94);
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 14px;
    box-shadow: 0 16px 36px rgba(42, 93, 156, 0.14);
}
.float-card strong { display: block; color: #163151; }
.float-card span { color: var(--muted); font-size: 13px; }
.float-card.status { left: 0; top: 22px; }
.float-card.asset { right: 0; bottom: 40px; }
.status-dot { width: 10px; height: 10px; background: #22b573; border-radius: 50%; display: inline-block; margin-right: 8px; }

/* unified download button */
.download-btn {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(70,139,223,0.28);
    border: 1px solid rgba(70,139,223,0.25);
    transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}
.download-btn:hover { transform: translateY(-2px); background: var(--primary-dark); box-shadow: 0 18px 34px rgba(70,139,223,0.34); }

/* content container, cards and grids */
.trust-grid,
.feature-grid,
.category-grid,
.scenario-grid,
.info-grid,
.topic-grid,
.faq-grid {
    display: grid;
    gap: 16px;
}
.trust-grid { grid-template-columns: 1fr; }
.trust-item,
.category-card,
.feature-card,
.scenario-card,
.info-card,
.faq-item,
.tip-card,
.step-card,
.panel-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 12px 30px rgba(42, 93, 156, 0.08);
}
.trust-item strong { display: block; font-size: 18px; color: #163151; }
.trust-item span { color: var(--muted); font-size: 14px; }

/* category nav and category card */
.category-card {
    position: relative;
    overflow: hidden;
    min-height: 156px;
}
.category-card::after {
    content: "";
    position: absolute;
    width: 88px;
    height: 88px;
    border-radius: 50%;
    background: rgba(70,139,223,0.08);
    right: -22px;
    bottom: -22px;
}
.category-card .icon,
.feature-card .icon,
.info-card .icon {
    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;
}
.category-card a { font-weight: 800; color: var(--primary-dark); }
.category-card:hover { transform: translateY(-3px); transition: transform .2s ease; }

.split-layout,
.security-layout,
.page-hero-grid,
.guide-layout {
    display: grid;
    gap: 24px;
    align-items: center;
}
.glass-panel {
    background: linear-gradient(145deg, rgba(255,255,255,0.94), rgba(238,247,255,0.90));
    border: 1px solid rgba(220,232,247,0.9);
    border-radius: 28px;
    padding: 26px;
    box-shadow: var(--shadow);
}
.metrics-row { display: grid; gap: 12px; margin-top: 18px; }
.metric {
    padding: 16px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid var(--line);
}
.metric strong { display: block; color: var(--primary-dark); }

/* security panel */
.security-panel {
    background: linear-gradient(135deg, #f7fbff, #ffffff 50%, #edf6ff);
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 26px;
}
.security-list,
.clean-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 12px;
}
.security-list li,
.clean-list li {
    padding: 14px 14px 14px 42px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 16px;
    position: relative;
    color: #42556d;
}
.security-list li::before,
.clean-list li::before {
    content: "✓";
    position: absolute;
    left: 14px;
    top: 13px;
    color: var(--primary);
    font-weight: 900;
}

/* process steps */
.steps { display: grid; gap: 16px; counter-reset: step; }
.step-card { position: relative; padding-top: 54px; }
.step-card::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    top: 18px;
    left: 22px;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
}

/* scenario card and FAQ item */
.scenario-card { background: linear-gradient(180deg, #ffffff, #f7fbff); }
.faq-item h3 { font-size: 18px; }
.faq-item p { margin-bottom: 0; }

/* page templates */
.page-hero {
    padding: 50px 0 30px;
    background:
      linear-gradient(135deg, rgba(70,139,223,0.12), rgba(255,255,255,0.8)),
      radial-gradient(circle at 82% 10%, rgba(70,139,223,0.16), transparent 26%);
}
.page-hero h1 { max-width: 840px; }
.page-hero p { max-width: 760px; font-size: 17px; }
.article-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 26px;
    box-shadow: var(--shadow);
}
.article-card p:last-child { margin-bottom: 0; }
.notice {
    border-left: 4px solid var(--primary);
    background: var(--primary-soft);
    padding: 18px;
    border-radius: 16px;
    color: #2d4a68;
}
.cta-section {
    text-align: center;
    background: linear-gradient(135deg, #f1f8ff, #ffffff);
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 34px 20px;
}
.cta-section p { max-width: 680px; margin-left: auto; margin-right: auto; }
.breadcrumb { color: var(--muted); font-size: 14px; margin-bottom: 16px; }
.breadcrumb a { color: var(--primary-dark); font-weight: 700; }

.download-panel {
    display: grid;
    gap: 20px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 30px;
    padding: 26px;
    box-shadow: var(--shadow);
}
.download-steps { counter-reset: dstep; display: grid; gap: 12px; }
.download-steps li {
    list-style: none;
    position: relative;
    padding: 14px 14px 14px 48px;
    background: var(--primary-soft);
    border-radius: 16px;
    color: #38516c;
}
.download-steps li::before {
    counter-increment: dstep;
    content: counter(dstep);
    position: absolute;
    left: 14px;
    top: 14px;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 900;
}

.site-footer {
    padding: 42px 0 20px;
    background: #f0f7ff;
    border-top: 1px solid var(--line);
}
.footer-grid { display: grid; gap: 24px; }
.footer-grid h3 { font-size: 16px; }
.footer-grid a { display: block; color: #43566e; margin: 8px 0; }
.footer-grid a:hover { color: var(--primary-dark); }
.footer-brand { margin-bottom: 10px; }
.footer-bottom {
    margin-top: 28px;
    padding-top: 18px;
    border-top: 1px solid var(--line);
    display: flex;
    flex-direction: column;
    gap: 8px;
    color: var(--muted);
    font-size: 13px;
}

@media (min-width: 640px) {
    .trust-grid { grid-template-columns: repeat(2, 1fr); }
    .category-grid, .feature-grid, .scenario-grid, .info-grid, .faq-grid, .topic-grid { grid-template-columns: repeat(2, 1fr); }
    .metrics-row { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
    .section { padding: 76px 0; }
    .nav-toggle { display: none; }
    .primary-nav {
        position: static;
        display: flex;
        align-items: center;
        gap: 4px;
        padding: 0;
        border: 0;
        box-shadow: none;
        background: transparent;
    }
    .primary-nav a { padding: 9px 12px; font-size: 15px; }
    .hero { padding: 84px 0 70px; }
    .hero-layout { grid-template-columns: minmax(0, 1.05fr) minmax(360px, .95fr); }
    .split-layout, .security-layout, .page-hero-grid, .guide-layout { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .category-grid, .feature-grid, .scenario-grid, .topic-grid { grid-template-columns: repeat(3, 1fr); }
    .faq-grid { grid-template-columns: repeat(2, 1fr); }
    .trust-grid { grid-template-columns: repeat(4, 1fr); }
    .steps { grid-template-columns: repeat(4, 1fr); }
    .footer-grid { grid-template-columns: 1.4fr repeat(3, 1fr); }
    .footer-bottom { flex-direction: row; justify-content: space-between; }
    .download-panel { grid-template-columns: 1fr 1.1fr; align-items: center; padding: 34px; }
}
@media (min-width: 1180px) {
    .hero-visual { min-height: 500px; }
    .float-card.status { left: -18px; }
    .float-card.asset { right: -14px; }
}