:root {
    --primary: rgb(70,139,223);
    --primary-dark: #245fa8;
    --primary-soft: #eaf3ff;
    --text: #172033;
    --muted: #60708a;
    --line: #dbe7f7;
    --panel: rgba(255, 255, 255, 0.84);
    --white: #ffffff;
    --bg: #f5f9ff;
    --radius: 22px;
    --shadow: 0 18px 48px rgba(70, 139, 223, 0.14);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    min-width: 320px;
    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, 0.16), transparent 34%), linear-gradient(180deg, #f7fbff 0%, #eef6ff 44%, #ffffff 100%);
    line-height: 1.72;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    width: min(100% - 32px, 1160px);
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255, 255, 255, 0.86);
    border-bottom: 1px solid rgba(219, 231, 247, 0.86);
    backdrop-filter: blur(18px);
}

.nav-wrap {
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: -0.02em;
}

.logo-img {
    width: 38px;
    height: 38px;
    border-radius: 12px;
}

.brand-text {
    color: #13213b;
    font-size: 18px;
}

.nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: #fff;
    color: var(--primary-dark);
    font-size: 22px;
}

.main-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    display: none;
    padding: 14px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: var(--shadow);
}

.main-nav.is-open {
    display: grid;
    gap: 4px;
}

.main-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: var(--muted);
    font-weight: 650;
    font-size: 15px;
}

.main-nav a.active,
.main-nav a:hover {
    color: var(--primary-dark);
    background: var(--primary-soft);
}

.hero {
    padding: 46px 0 36px;
}

.hero-layout {
    display: grid;
    gap: 26px;
    align-items: center;
}

.eyebrow,
.page-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 14px;
    padding: 7px 12px;
    border: 1px solid rgba(70, 139, 223, 0.2);
    border-radius: 999px;
    background: rgba(70, 139, 223, 0.08);
    color: var(--primary-dark);
    font-size: 13px;
    font-weight: 750;
}

.hero h1,
.page-hero h1 {
    margin: 0 0 16px;
    font-size: clamp(34px, 7vw, 64px);
    line-height: 1.06;
    letter-spacing: -0.045em;
}

.hero p,
.page-hero p,
.lead {
    margin: 0 0 22px;
    color: var(--muted);
    font-size: 17px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 14px;
}

.download-btn {
    display: inline-flex;
    min-height: 48px;
    align-items: center;
    justify-content: center;
    padding: 13px 24px;
    border-radius: 999px;
    background: linear-gradient(135deg, var(--primary), #5aa9ff);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 12px 28px rgba(70, 139, 223, 0.28);
    transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 16px 32px rgba(70, 139, 223, 0.34);
}

.text-link {
    color: var(--primary-dark);
    font-weight: 750;
}

.hero-visual {
    position: relative;
    padding: 18px;
    border: 1px solid rgba(70, 139, 223, 0.16);
    border-radius: 30px;
    background: linear-gradient(145deg, rgba(255,255,255,0.92), rgba(235,244,255,0.8));
    box-shadow: var(--shadow);
    overflow: hidden;
}

.hero-visual::before {
    content: "";
    position: absolute;
    inset: auto -50px -70px auto;
    width: 220px;
    height: 220px;
    border-radius: 50%;
    background: rgba(70,139,223,0.14);
}

.app-card {
    position: relative;
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
    align-items: center;
}

.app-card img {
    width: min(260px, 72vw);
    margin: 0 auto;
    filter: drop-shadow(0 18px 28px rgba(19, 33, 59, 0.18));
}

.status-card,
.floating-card,
.info-card,
.tip-card,
.note-card {
    border: 1px solid rgba(70,139,223,0.16);
    border-radius: 20px;
    background: var(--panel);
    box-shadow: 0 12px 30px rgba(70,139,223,0.1);
}

.status-card {
    padding: 18px;
}

.status-card strong {
    display: block;
    margin-bottom: 6px;
    color: var(--primary-dark);
}

.security-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 9px;
    margin-top: 14px;
}

.security-tags span,
.tag {
    display: inline-flex;
    align-items: center;
    padding: 7px 10px;
    border-radius: 999px;
    background: #fff;
    border: 1px solid var(--line);
    color: var(--primary-dark);
    font-size: 12px;
    font-weight: 760;
}

.section {
    padding: 48px 0;
}

.section-heading {
    max-width: 720px;
    margin: 0 0 26px;
}

.section-heading.center {
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.section-heading h2,
.content-block h2 {
    margin: 0 0 12px;
    font-size: clamp(25px, 4vw, 40px);
    line-height: 1.18;
    letter-spacing: -0.03em;
}

.section-heading p,
.content-block p {
    margin: 0;
    color: var(--muted);
}

.trust-grid,
.category-grid,
.feature-grid,
.scenario-grid,
.related-grid,
.cards-grid {
    display: grid;
    gap: 16px;
}

.trust-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.trust-item,
.category-card,
.feature-card,
.scenario-card,
.faq-item,
.step-card,
.related-card {
    border: 1px solid rgba(70,139,223,0.14);
    border-radius: var(--radius);
    background: rgba(255,255,255,0.9);
    box-shadow: 0 12px 30px rgba(70,139,223,0.08);
}

.trust-item {
    padding: 18px;
}

.trust-item strong {
    display: block;
    margin-bottom: 6px;
    color: #13213b;
}

.trust-item span {
    color: var(--muted);
    font-size: 14px;
}

.category-card,
.feature-card,
.scenario-card,
.related-card {
    padding: 20px;
    transition: transform 0.18s ease, border-color 0.18s ease;
}

.category-card:hover,
.related-card:hover {
    transform: translateY(-3px);
    border-color: rgba(70,139,223,0.34);
}

.category-card h3,
.feature-card h3,
.scenario-card h3,
.related-card h3,
.step-card h3 {
    margin: 0 0 9px;
    font-size: 19px;
}

.category-card p,
.feature-card p,
.scenario-card p,
.related-card p,
.step-card p,
.tip-card p,
.note-card p {
    margin: 0;
    color: var(--muted);
}

.category-card .arrow,
.related-card .arrow {
    display: inline-block;
    margin-top: 14px;
    color: var(--primary-dark);
    font-weight: 800;
}

.split-layout,
.security-layout,
.content-layout {
    display: grid;
    gap: 22px;
    align-items: center;
}

.visual-panel,
.security-panel,
.content-panel {
    padding: 22px;
    border: 1px solid rgba(70,139,223,0.14);
    border-radius: 28px;
    background: linear-gradient(145deg, rgba(255,255,255,0.96), rgba(235,244,255,0.86));
    box-shadow: var(--shadow);
}

.metric-row,
.check-row {
    display: grid;
    gap: 12px;
}

.metric,
.check-item {
    padding: 16px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid var(--line);
}

.metric b,
.check-item b {
    display: block;
    margin-bottom: 4px;
    color: var(--primary-dark);
}

.steps {
    display: grid;
    gap: 16px;
    counter-reset: step;
}

.step-card {
    position: relative;
    padding: 22px;
    overflow: hidden;
}

.step-card::before {
    counter-increment: step;
    content: "0" counter(step);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    margin-bottom: 14px;
    border-radius: 14px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 900;
}

.faq-list {
    display: grid;
    gap: 14px;
}

.faq-item {
    padding: 18px;
}

.faq-item h3 {
    margin: 0 0 8px;
    font-size: 18px;
}

.faq-item p {
    margin: 0;
    color: var(--muted);
}

.cta-section {
    padding: 42px 20px;
    border: 1px solid rgba(70,139,223,0.16);
    border-radius: 30px;
    background: radial-gradient(circle at top right, rgba(70,139,223,0.18), transparent 30%), linear-gradient(135deg, #ffffff, #eaf3ff);
    box-shadow: var(--shadow);
    text-align: center;
}

.cta-section h2 {
    margin: 0 0 12px;
    font-size: clamp(25px, 5vw, 42px);
    letter-spacing: -0.03em;
}

.cta-section p {
    max-width: 680px;
    margin: 0 auto 22px;
    color: var(--muted);
}

.page-hero {
    padding: 48px 0 28px;
}

.article-card {
    padding: 24px;
    border: 1px solid rgba(70,139,223,0.14);
    border-radius: 28px;
    background: rgba(255,255,255,0.92);
    box-shadow: var(--shadow);
}

.article-card h2,
.article-card h3 {
    margin-top: 0;
}

.article-card p,
.article-card li {
    color: var(--muted);
}

.article-actions {
    margin-top: 24px;
}

.tip-card,
.note-card {
    padding: 20px;
    margin-top: 18px;
}

.tip-card h3,
.note-card h3 {
    margin: 0 0 10px;
}

.notice-list {
    margin: 0;
    padding-left: 20px;
}

.notice-list li + li {
    margin-top: 8px;
}

.download-panel {
    max-width: 780px;
    margin: 0 auto;
    text-align: center;
}

.download-panel .article-actions {
    display: flex;
    justify-content: center;
}

.site-footer {
    margin-top: 56px;
    padding: 42px 0 24px;
    background: #10223b;
    color: rgba(255,255,255,0.78);
}

.footer-grid {
    display: grid;
    gap: 22px;
}

.footer-brand {
    margin-bottom: 10px;
    color: #fff;
    font-size: 20px;
    font-weight: 850;
}

.site-footer h3 {
    margin: 0 0 12px;
    color: #fff;
    font-size: 16px;
}

.site-footer a {
    display: block;
    margin: 8px 0;
    color: rgba(255,255,255,0.78);
}

.footer-bottom {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-top: 28px;
    padding-top: 18px;
    border-top: 1px solid rgba(255,255,255,0.12);
    font-size: 13px;
}

@media (min-width: 700px) {
    .container {
        width: min(100% - 48px, 1160px);
    }

    .trust-grid,
    .category-grid,
    .feature-grid,
    .scenario-grid,
    .related-grid,
    .cards-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .steps {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .footer-grid {
        grid-template-columns: 1.5fr 1fr 1fr 1fr;
    }

    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
}

@media (min-width: 960px) {
    .nav-toggle {
        display: none;
    }

    .main-nav {
        position: static;
        display: flex;
        align-items: center;
        gap: 4px;
        padding: 0;
        border: 0;
        box-shadow: none;
        background: transparent;
    }

    .hero {
        padding: 70px 0 56px;
    }

    .hero-layout,
    .split-layout,
    .security-layout,
    .content-layout {
        grid-template-columns: minmax(0, 1.04fr) minmax(0, 0.96fr);
        gap: 46px;
    }

    .app-card {
        grid-template-columns: minmax(210px, 0.82fr) minmax(230px, 1fr);
    }

    .category-grid,
    .feature-grid,
    .scenario-grid,
    .related-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .trust-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }

    .steps {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }

    .section {
        padding: 66px 0;
    }

    .article-card {
        padding: 34px;
    }
}

@media (max-width: 420px) {
    .trust-grid {
        grid-template-columns: 1fr;
    }

    .download-btn {
        width: 100%;
    }

    .hero-actions {
        align-items: stretch;
    }
}