* {
    box-sizing: border-box;
}

:root {
    --primary: rgb(70,139,223);
    --primary-strong: #2f72c8;
    --ink: #102033;
    --muted: #5e6f83;
    --soft: #f5f9ff;
    --soft-blue: #eef6ff;
    --line: #dbe8f7;
    --card: rgba(255,255,255,.88);
    --radius: 22px;
    --shadow: 0 18px 50px rgba(33,91,154,.10);
}

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, #f8fbff 0%, #ffffff 38%, #f6faff 100%);
    line-height: 1.72;
    overflow-x: hidden;
}

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

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

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    border-bottom: 1px solid rgba(219,232,247,.72);
    background: rgba(255,255,255,.86);
    backdrop-filter: blur(18px);
}

.header-inner {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.brand,
.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: .02em;
}

.brand img,
.footer-brand img {
    width: 36px;
    height: 36px;
    border-radius: 12px;
}

.nav-toggle {
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 14px;
    width: 44px;
    height: 44px;
    color: var(--ink);
    font-size: 22px;
}

.site-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    display: none;
    flex-direction: column;
    padding: 12px;
    background: rgba(255,255,255,.96);
    border: 1px solid var(--line);
    border-radius: 20px;
    box-shadow: var(--shadow);
}

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

.site-nav a {
    padding: 11px 13px;
    border-radius: 14px;
    color: #405166;
    font-size: 15px;
}

.site-nav a:hover,
.site-nav a.active {
    color: var(--primary-strong);
    background: var(--soft-blue);
}

.section,
.page-section {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
    padding: 56px 0;
}

.narrow {
    width: min(860px, calc(100% - 32px));
}

.centered-hero {
    position: relative;
    padding: 82px 0 38px;
    text-align: center;
    overflow: hidden;
}

.centered-hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 50% 8%, rgba(70,139,223,.18), transparent 32%),
        linear-gradient(180deg, rgba(238,246,255,.92), rgba(255,255,255,.35));
    z-index: -1;
}

.hero-inner {
    width: min(880px, calc(100% - 32px));
    margin: 0 auto;
}

.eyebrow,
.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--primary-strong);
    background: rgba(70,139,223,.10);
    border: 1px solid rgba(70,139,223,.16);
    border-radius: 999px;
    padding: 7px 12px;
    font-size: 13px;
    font-weight: 700;
}

h1,
h2,
h3 {
    margin: 0;
    line-height: 1.18;
    letter-spacing: -.03em;
}

h1 {
    margin-top: 18px;
    font-size: clamp(36px, 9vw, 68px);
}

h2 {
    font-size: clamp(28px, 6vw, 44px);
}

h3 {
    font-size: 20px;
}

.lead {
    margin: 18px auto 0;
    color: var(--muted);
    font-size: 17px;
    max-width: 780px;
}

.hero-actions,
.cta-actions {
    margin-top: 28px;
    display: flex;
    justify-content: center;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 50px;
    padding: 0 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(70,139,223,.26);
    transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}

.download-btn:hover {
    transform: translateY(-1px);
    background: var(--primary-strong);
    box-shadow: 0 18px 34px rgba(70,139,223,.32);
}

.safety-tags,
.tag-list {
    margin-top: 18px;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
}

.safety-tags span,
.tag-list span {
    border: 1px solid var(--line);
    background: rgba(255,255,255,.78);
    color: #50657d;
    border-radius: 999px;
    padding: 8px 12px;
    font-size: 13px;
}

.product-bento {
    width: min(1080px, calc(100% - 32px));
    margin: 36px auto 0;
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.product-card,
.card,
.category-card,
.feature-card,
.security-principles,
.scenario-card,
.faq-item,
.guide-card,
.note-card,
.step-card {
    background: var(--card);
    border: 1px solid rgba(219,232,247,.88);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.product-card {
    min-height: 420px;
    display: grid;
    place-items: center;
    padding: 28px;
    background:
        radial-gradient(circle at 40% 12%, rgba(70,139,223,.13), transparent 38%),
        linear-gradient(145deg, #ffffff 0%, #f3f8ff 100%);
}

.phone-shell {
    width: min(280px, 86%);
    padding: 16px;
    border-radius: 34px;
    background: #f8fbff;
    box-shadow: inset 0 0 0 1px rgba(70,139,223,.14), 0 28px 60px rgba(26,73,132,.16);
}

.status-stack {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.status-card {
    padding: 20px;
    border-radius: var(--radius);
    background: rgba(255,255,255,.86);
    border: 1px solid var(--line);
    box-shadow: 0 14px 36px rgba(33,91,154,.08);
}

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

.status-card p,
.card p,
.category-card p,
.feature-card p,
.scenario-card p,
.guide-card p,
.note-card p,
.step-card p,
.faq-item p {
    margin: 0;
    color: var(--muted);
}

.section-head {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 24px;
}

.section-head.center {
    align-items: center;
    text-align: center;
}

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

.feature-grid,
.scenario-grid,
.help-grid,
.card-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.card,
.feature-card,
.scenario-card,
.guide-card,
.note-card,
.step-card {
    padding: 22px;
}

.card .icon,
.feature-card .icon,
.category-card .icon {
    width: 42px;
    height: 42px;
    border-radius: 15px;
    background: rgba(70,139,223,.11);
    color: var(--primary-strong);
    display: grid;
    place-items: center;
    font-weight: 900;
    margin-bottom: 16px;
}

.card h3,
.feature-card h3,
.category-card h3,
.scenario-card h3,
.guide-card h3 {
    margin-bottom: 10px;
}

.roadmap {
    position: relative;
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}

.roadmap::before {
    content: "";
    position: absolute;
    left: 22px;
    top: 20px;
    bottom: 20px;
    width: 2px;
    background: linear-gradient(var(--primary), rgba(70,139,223,.05));
}

.roadmap-item {
    position: relative;
    display: grid;
    grid-template-columns: 48px 1fr;
    gap: 14px;
    align-items: start;
}

.roadmap-num {
    position: relative;
    z-index: 1;
    width: 46px;
    height: 46px;
    border-radius: 16px;
    background: var(--primary);
    color: #fff;
    display: grid;
    place-items: center;
    font-weight: 900;
    box-shadow: 0 12px 24px rgba(70,139,223,.25);
}

.roadmap-card {
    padding: 20px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.roadmap-card p {
    color: var(--muted);
    margin: 8px 0 12px;
}

.text-link {
    color: var(--primary-strong);
    font-weight: 800;
}

.category-bento,
.bento-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
}

.category-card {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    min-height: 190px;
    padding: 22px;
}

.category-card.big,
.feature-card.large {
    background:
        radial-gradient(circle at 88% 8%, rgba(70,139,223,.14), transparent 34%),
        rgba(255,255,255,.90);
}

.category-card a,
.scenario-card a,
.card a,
.guide-card a {
    margin-top: 16px;
    color: var(--primary-strong);
    font-weight: 800;
}

.feature-card.small {
    min-height: 150px;
}

.security-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    align-items: start;
}

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

.security-principles {
    padding: 22px;
}

.principle-list,
.check-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 12px;
}

.principle-list li,
.check-list li {
    padding: 14px 14px 14px 42px;
    border-radius: 16px;
    border: 1px solid var(--line);
    background: #fff;
    position: relative;
    color: #3b5068;
}

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

.faq-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}

.faq-item {
    padding: 20px;
}

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

.cta-section {
    width: min(980px, calc(100% - 32px));
    margin: 0 auto 64px;
    padding: 42px 22px;
    text-align: center;
    border-radius: 30px;
    border: 1px solid rgba(70,139,223,.16);
    background:
        radial-gradient(circle at 20% 20%, rgba(70,139,223,.13), transparent 30%),
        linear-gradient(135deg, #ffffff 0%, #eef6ff 100%);
    box-shadow: var(--shadow);
}

.cta-section p {
    color: var(--muted);
    max-width: 680px;
    margin: 14px auto 0;
}

.page-hero {
    width: min(980px, calc(100% - 32px));
    margin: 0 auto;
    padding: 62px 0 28px;
    text-align: left;
}

.page-hero.center {
    text-align: center;
}

.page-hero p {
    color: var(--muted);
    max-width: 780px;
}

.doc-layout {
    width: min(1060px, calc(100% - 32px));
    margin: 0 auto 64px;
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
}

.article-card {
    background: rgba(255,255,255,.92);
    border: 1px solid var(--line);
    border-radius: 26px;
    padding: 24px;
    box-shadow: var(--shadow);
}

.article-card p {
    color: #435970;
}

.article-card h2 {
    font-size: clamp(24px, 5vw, 34px);
    margin: 26px 0 12px;
}

.article-card h2:first-child {
    margin-top: 0;
}

.side-panel {
    display: grid;
    gap: 16px;
}

.guide-steps {
    counter-reset: guide;
    display: grid;
    gap: 14px;
    margin: 20px 0;
}

.guide-step {
    position: relative;
    padding: 18px 18px 18px 64px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: #fff;
}

.guide-step::before {
    counter-increment: guide;
    content: counter(guide, decimal-leading-zero);
    position: absolute;
    left: 16px;
    top: 18px;
    width: 34px;
    height: 34px;
    border-radius: 12px;
    background: rgba(70,139,223,.12);
    color: var(--primary-strong);
    display: grid;
    place-items: center;
    font-weight: 900;
}

.guide-step h3 {
    margin-bottom: 6px;
}

.info-strip {
    display: grid;
    gap: 14px;
    margin: 18px 0;
}

.info-strip .mini {
    padding: 16px;
    border-radius: 18px;
    background: var(--soft-blue);
    border: 1px solid rgba(70,139,223,.14);
}

.download-block {
    margin-top: 26px;
    display: flex;
    justify-content: flex-start;
}

.download-block.center {
    justify-content: center;
}

.site-footer {
    border-top: 1px solid var(--line);
    background: #f8fbff;
    padding: 34px 0 20px;
}

.footer-inner {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

.footer-inner p {
    color: var(--muted);
    max-width: 560px;
}

.footer-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}

.footer-links a {
    padding: 10px 12px;
    border-radius: 14px;
    color: #50657d;
    background: #fff;
    border: 1px solid var(--line);
}

.footer-bottom {
    width: min(1120px, calc(100% - 32px));
    margin: 24px auto 0;
    color: #7a8898;
    font-size: 13px;
}

@media (min-width: 720px) {
    .feature-grid,
    .scenario-grid,
    .help-grid,
    .card-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

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

    .footer-inner {
        grid-template-columns: 1.4fr .8fr;
        align-items: start;
    }
}

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

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

    .product-bento {
        grid-template-columns: 1.45fr .8fr;
        align-items: stretch;
    }

    .product-card {
        min-height: 560px;
    }

    .status-stack {
        grid-template-rows: repeat(4, 1fr);
    }

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

    .feature-grid .card:nth-child(1),
    .feature-grid .card:nth-child(2) {
        grid-column: span 2;
    }

    .roadmap {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .roadmap::before {
        left: 7%;
        right: 7%;
        top: 23px;
        bottom: auto;
        width: auto;
        height: 2px;
    }

    .roadmap-item {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    .roadmap-num {
        margin-bottom: 4px;
    }

    .category-bento {
        grid-template-columns: repeat(4, minmax(0, 1fr));
        grid-auto-rows: minmax(190px, auto);
    }

    .category-card.big {
        grid-column: span 2;
        grid-row: span 2;
    }

    .bento-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
        grid-auto-rows: minmax(170px, auto);
    }

    .feature-card.large {
        grid-column: span 2;
        grid-row: span 2;
    }

    .feature-card.medium {
        grid-column: span 2;
    }

    .security-layout {
        grid-template-columns: 1.05fr .95fr;
        gap: 36px;
    }

    .doc-layout {
        grid-template-columns: minmax(0, 1fr) 320px;
        align-items: start;
    }

    .side-panel {
        position: sticky;
        top: 94px;
    }

    .scenario-grid {
        grid-template-columns: repeat(5, minmax(0, 1fr));
    }

    .scenario-card:nth-child(1),
    .scenario-card:nth-child(2) {
        grid-column: span 2;
    }

    .scenario-card:nth-child(3) {
        grid-column: span 1;
    }
}