:root {
    --primary: rgb(70,139,223);
    --primary-dark: #1d5fae;
    --primary-soft: #eaf4ff;
    --ink: #102033;
    --muted: #5d6d7e;
    --line: #d9e6f5;
    --card: #ffffff;
    --bg: #f5f9ff;
    --shadow: 0 18px 50px rgba(31, 87, 140, 0.12);
    --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);
    line-height: 1.75;
    background:
        radial-gradient(circle at 10% 0%, rgba(70,139,223,0.16), transparent 30%),
        radial-gradient(circle at 90% 10%, rgba(121,188,255,0.18), transparent 34%),
        linear-gradient(180deg, #f7fbff 0%, #eef6ff 48%, #ffffff 100%);
    min-width: 0;
    overflow-x: hidden;
}

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

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

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

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255,255,255,0.86);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(216,230,246,0.86);
}

.header-inner {
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: #13263b;
}

.logo img {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    box-shadow: 0 10px 22px rgba(70,139,223,0.22);
}

.nav-toggle {
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 999px;
    padding: 8px 14px;
    color: var(--primary-dark);
    font-weight: 700;
}

.site-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    display: none;
    flex-direction: column;
    gap: 8px;
    padding: 14px;
    border-radius: 18px;
    background: rgba(255,255,255,0.96);
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
}

.site-nav.is-open {
    display: flex;
}

.site-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #25405e;
    font-size: 15px;
}

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

.section {
    padding: 58px 0;
}

.section-title {
    max-width: 760px;
    margin: 0 auto 28px;
    text-align: center;
}

.section-title h2 {
    margin: 0 0 10px;
    font-size: clamp(26px, 4vw, 38px);
    line-height: 1.22;
    letter-spacing: -0.03em;
}

.section-title p {
    margin: 0;
    color: var(--muted);
}

.hero {
    padding: 58px 0 34px;
}

.hero-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
    align-items: center;
}

.hero-copy h1,
.page-hero h1 {
    margin: 0 0 18px;
    font-size: clamp(34px, 7vw, 62px);
    line-height: 1.08;
    letter-spacing: -0.055em;
}

.hero-copy p,
.page-hero p {
    margin: 0 0 18px;
    color: #52667a;
    font-size: 17px;
}

.hero-tags,
.tag-list {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 18px 0 24px;
}

.badge,
.hero-tags span,
.tag-list span {
    display: inline-flex;
    align-items: center;
    padding: 7px 11px;
    border-radius: 999px;
    background: rgba(70,139,223,0.1);
    color: var(--primary-dark);
    border: 1px solid rgba(70,139,223,0.22);
    font-weight: 700;
    font-size: 13px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 12px 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(70,139,223,0.28);
    border: 0;
    transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
    cursor: pointer;
}

.download-btn:hover {
    transform: translateY(-2px);
    background: var(--primary-dark);
    box-shadow: 0 18px 34px rgba(70,139,223,0.35);
}

.hero-visual {
    position: relative;
    padding: 18px;
    border-radius: 30px;
    background:
        linear-gradient(135deg, rgba(255,255,255,0.95), rgba(232,244,255,0.72)),
        radial-gradient(circle at 70% 20%, rgba(70,139,223,0.18), transparent 35%);
    border: 1px solid rgba(218,232,248,0.9);
    box-shadow: var(--shadow);
    min-height: 400px;
    overflow: hidden;
}

.app-frame {
    width: min(280px, 78vw);
    margin: 0 auto;
    padding: 12px;
    border-radius: 32px;
    background: #ffffff;
    box-shadow: 0 26px 50px rgba(26,76,127,0.16);
    border: 1px solid #e1eefc;
}

.status-card,
.float-chip {
    background: rgba(255,255,255,0.92);
    border: 1px solid rgba(217,230,245,0.95);
    box-shadow: 0 14px 30px rgba(31,87,140,0.12);
    border-radius: 18px;
}

.status-card {
    margin: -12px auto 0;
    padding: 14px;
    width: min(320px, 92%);
}

.status-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
}

.status-dot {
    width: 10px;
    height: 10px;
    background: var(--primary);
    border-radius: 50%;
    box-shadow: 0 0 0 6px rgba(70,139,223,0.12);
}

.float-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: 10px;
    margin-top: 14px;
}

.float-chip {
    padding: 10px 12px;
    color: #244463;
    font-weight: 700;
    font-size: 13px;
}

.trust-grid,
.category-grid,
.feature-grid,
.scenario-grid,
.article-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.trust-item,
.category-card,
.feature-card,
.scenario-card,
.article-card,
.info-card,
.faq-item,
.step-card,
.security-card,
.note-card {
    background: rgba(255,255,255,0.88);
    border: 1px solid rgba(217,230,245,0.95);
    border-radius: var(--radius);
    box-shadow: 0 12px 30px rgba(31,87,140,0.08);
}

.trust-item {
    padding: 20px;
}

.trust-item strong {
    display: block;
    font-size: 18px;
    margin-bottom: 6px;
}

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

.category-card,
.feature-card,
.scenario-card,
.article-card {
    padding: 22px;
    transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}

.category-card:hover,
.article-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow);
    border-color: rgba(70,139,223,0.28);
}

.category-card h3,
.feature-card h3,
.scenario-card h3,
.article-card h3 {
    margin: 0 0 10px;
    font-size: 20px;
}

.category-card p,
.feature-card p,
.scenario-card p,
.article-card p {
    color: var(--muted);
    margin: 0 0 14px;
}

.category-card span,
.article-card span {
    color: var(--primary-dark);
    font-weight: 800;
}

.split-layout,
.security-layout,
.page-grid,
.download-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
    align-items: start;
}

.panel {
    padding: 26px;
    border-radius: 26px;
    background: linear-gradient(135deg, rgba(255,255,255,0.96), rgba(235,246,255,0.8));
    border: 1px solid rgba(216,230,246,0.9);
    box-shadow: var(--shadow);
}

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

.panel p {
    color: var(--muted);
}

.security-panel {
    padding: 24px;
    border-radius: 26px;
    background:
        linear-gradient(135deg, rgba(70,139,223,0.12), rgba(255,255,255,0.86)),
        #ffffff;
    border: 1px solid rgba(70,139,223,0.18);
}

.security-list {
    display: grid;
    gap: 12px;
    padding: 0;
    margin: 18px 0 0;
    list-style: none;
}

.security-list li {
    padding: 14px 14px 14px 44px;
    border-radius: 16px;
    background: rgba(255,255,255,0.78);
    border: 1px solid rgba(216,230,246,0.88);
    position: relative;
}

.security-list li::before {
    content: "✓";
    position: absolute;
    left: 16px;
    top: 14px;
    color: var(--primary);
    font-weight: 900;
}

.steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
    counter-reset: step;
}

.step-card {
    padding: 20px;
    position: relative;
}

.step-card::before {
    counter-increment: step;
    content: counter(step);
    display: inline-flex;
    width: 34px;
    height: 34px;
    border-radius: 12px;
    align-items: center;
    justify-content: center;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    margin-bottom: 12px;
}

.step-card h3 {
    margin: 0 0 8px;
}

.step-card p {
    margin: 0;
    color: var(--muted);
}

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

.faq-item {
    padding: 20px;
}

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

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

.cta-section {
    text-align: center;
    padding: 42px 24px;
    border-radius: 30px;
    background:
        radial-gradient(circle at 15% 15%, rgba(70,139,223,0.18), transparent 28%),
        linear-gradient(135deg, #ffffff, #eaf4ff);
    border: 1px solid rgba(216,230,246,0.92);
    box-shadow: var(--shadow);
}

.cta-section h2 {
    margin: 0 0 12px;
    font-size: clamp(26px, 5vw, 42px);
}

.cta-section p {
    max-width: 720px;
    margin: 0 auto 20px;
    color: var(--muted);
}

.page-hero {
    padding: 54px 0 24px;
}

.page-hero-card {
    border-radius: 30px;
    padding: 32px 22px;
    background:
        radial-gradient(circle at 80% 0%, rgba(70,139,223,0.14), transparent 30%),
        linear-gradient(135deg, rgba(255,255,255,0.96), rgba(235,246,255,0.88));
    border: 1px solid rgba(216,230,246,0.95);
    box-shadow: var(--shadow);
}

.content-block {
    padding: 28px 0 58px;
}

.prose {
    font-size: 16px;
}

.prose p {
    color: #4f6173;
    margin: 0 0 16px;
}

.prose h2 {
    margin: 28px 0 12px;
    font-size: 25px;
    line-height: 1.28;
}

.prose ul,
.prose ol {
    padding-left: 20px;
    color: #4f6173;
}

.prose li {
    margin: 8px 0;
}

.note-card {
    padding: 20px;
    background: linear-gradient(135deg, #ffffff, #eef7ff);
}

.note-card h3 {
    margin-top: 0;
}

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

.download-layout .panel {
    height: 100%;
}

.site-footer {
    background: #f0f7ff;
    border-top: 1px solid rgba(216,230,246,0.9);
    padding: 42px 0 22px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
}

.footer-logo {
    font-size: 22px;
    font-weight: 900;
    margin-bottom: 10px;
}

.site-footer p {
    color: var(--muted);
    margin: 0;
}

.site-footer h3 {
    margin: 0 0 10px;
    font-size: 16px;
}

.site-footer a {
    display: block;
    color: #51677d;
    margin: 6px 0;
}

.site-footer a:hover {
    color: var(--primary-dark);
}

.footer-bottom {
    display: flex;
    flex-direction: column;
    gap: 8px;
    color: #6b7b8c;
    font-size: 13px;
    padding-top: 24px;
    margin-top: 24px;
    border-top: 1px solid rgba(216,230,246,0.9);
}

@media (min-width: 640px) {
    .trust-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .category-grid,
    .feature-grid,
    .scenario-grid,
    .article-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .float-list {
        grid-template-columns: repeat(3, 1fr);
    }

    .footer-grid {
        grid-template-columns: 1.3fr repeat(3, 1fr);
    }
}

@media (min-width: 900px) {
    .nav-toggle {
        display: none;
    }

    .site-nav {
        position: static;
        display: flex;
        flex-direction: row;
        padding: 0;
        background: transparent;
        border: 0;
        box-shadow: none;
        gap: 4px;
    }

    .site-nav a {
        padding: 8px 12px;
    }

    .hero {
        padding: 78px 0 44px;
    }

    .hero-layout {
        grid-template-columns: 1.03fr .97fr;
        gap: 48px;
    }

    .hero-visual {
        min-height: 520px;
        padding: 28px;
    }

    .app-frame {
        width: 320px;
    }

    .status-card {
        position: absolute;
        left: 24px;
        bottom: 36px;
        width: 285px;
        margin: 0;
    }

    .float-list {
        position: absolute;
        right: 24px;
        top: 72px;
        width: 210px;
        grid-template-columns: 1fr;
    }

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

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

    .split-layout,
    .security-layout,
    .page-grid,
    .download-layout {
        grid-template-columns: 1.1fr .9fr;
        gap: 34px;
    }

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

    .page-hero-card {
        padding: 46px;
    }

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

@media (min-width: 1160px) {
    .section {
        padding: 74px 0;
    }

    .hero-copy p,
    .page-hero p {
        font-size: 18px;
    }
}