* {
    box-sizing: border-box;
}

:root {
    --primary: rgb(70,139,223);
    --primary-dark: rgb(34,86,158);
    --primary-soft: rgb(232,243,255);
    --blue-50: rgb(246,250,255);
    --blue-100: rgb(236,246,255);
    --ink: rgb(18,32,52);
    --muted: rgb(93,109,132);
    --line: rgba(70,139,223,0.18);
    --card: rgba(255,255,255,0.92);
    --shadow: 0 16px 40px rgba(39, 94, 160, 0.10);
    --radius: 22px;
}

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, #f8fbff 0%, #eef7ff 45%, #ffffff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    z-index: -1;
    background:
        radial-gradient(circle at 8% 6%, rgba(70,139,223,0.16), transparent 34%),
        radial-gradient(circle at 92% 18%, rgba(70,139,223,0.12), transparent 30%);
}

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);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(70,139,223,0.14);
}

.header-inner {
    width: min(100% - 28px, 1160px);
    margin: 0 auto;
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

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

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

.brand-name {
    font-size: 18px;
}

.nav-toggle {
    width: 44px;
    height: 44px;
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 14px;
    display: grid;
    place-content: center;
    gap: 5px;
    cursor: pointer;
}

.nav-toggle span {
    width: 20px;
    height: 2px;
    background: var(--primary-dark);
    border-radius: 999px;
}

.site-nav {
    position: absolute;
    left: 14px;
    right: 14px;
    top: 76px;
    display: none;
    flex-direction: column;
    padding: 12px;
    background: rgba(255,255,255,0.96);
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: var(--shadow);
}

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

.site-nav a {
    padding: 12px 14px;
    color: var(--muted);
    border-radius: 12px;
    font-size: 15px;
    font-weight: 650;
}

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

section {
    padding: 52px 0;
}

.hero {
    padding: 58px 0 36px;
}

.hero-layout {
    display: grid;
    gap: 34px;
    align-items: center;
}

.eyebrow,
.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    width: fit-content;
    padding: 7px 12px;
    border: 1px solid var(--line);
    border-radius: 999px;
    color: var(--primary-dark);
    background: rgba(255,255,255,0.78);
    font-size: 13px;
    font-weight: 750;
}

h1,
h2,
h3 {
    line-height: 1.25;
    margin: 0 0 14px;
}

h1 {
    font-size: clamp(32px, 7vw, 58px);
    letter-spacing: -0.05em;
}

h2 {
    font-size: clamp(26px, 4.6vw, 40px);
    letter-spacing: -0.035em;
}

h3 {
    font-size: 20px;
}

.lead {
    font-size: 17px;
    color: var(--muted);
    margin: 0 0 24px;
}

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

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
    margin: 26px 0 20px;
}

.download-btn {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    min-height: 48px;
    padding: 0 24px;
    border-radius: 999px;
    background: linear-gradient(135deg, var(--primary), rgb(86,160,242));
    color: #fff;
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(70,139,223,0.24);
    border: 0;
    cursor: pointer;
    transition: transform .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 18px 32px rgba(70,139,223,0.30);
}

.security-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 18px;
}

.security-tags span,
.inline-tag {
    padding: 7px 11px;
    border-radius: 999px;
    background: #fff;
    color: var(--primary-dark);
    border: 1px solid var(--line);
    font-size: 13px;
    font-weight: 700;
}

.hero-visual {
    position: relative;
    padding: 18px;
    border-radius: 30px;
    background: linear-gradient(145deg, rgba(255,255,255,0.72), rgba(230,244,255,0.72));
    border: 1px solid rgba(255,255,255,0.9);
    box-shadow: var(--shadow);
    min-height: 420px;
    display: grid;
    place-items: center;
    overflow: hidden;
}

.hero-visual::before {
    content: "";
    position: absolute;
    width: 230px;
    height: 230px;
    border-radius: 999px;
    background: rgba(70,139,223,0.14);
    right: -60px;
    top: -60px;
}

.app-shot {
    width: min(260px, 72vw);
    position: relative;
    z-index: 2;
    filter: drop-shadow(0 24px 34px rgba(38,82,140,0.18));
}

.float-card {
    position: absolute;
    z-index: 3;
    background: rgba(255,255,255,0.88);
    border: 1px solid rgba(70,139,223,0.15);
    border-radius: 18px;
    padding: 14px;
    box-shadow: 0 14px 30px rgba(39,94,160,0.12);
    color: var(--muted);
    font-size: 13px;
}

.float-card strong {
    display: block;
    color: var(--ink);
    font-size: 15px;
    margin-bottom: 4px;
}

.status-card {
    left: 18px;
    top: 30px;
}

.key-card {
    right: 18px;
    bottom: 54px;
}

.protect-card {
    left: 22px;
    bottom: 28px;
}

.trust-strip {
    padding: 20px 0 34px;
}

.trust-grid {
    display: grid;
    gap: 14px;
}

.trust-item {
    padding: 18px;
    border-radius: 20px;
    background: rgba(255,255,255,0.82);
    border: 1px solid var(--line);
    box-shadow: 0 8px 26px rgba(39,94,160,0.06);
}

.trust-item strong {
    display: block;
    color: var(--primary-dark);
    margin-bottom: 5px;
}

.section-title {
    max-width: 760px;
    margin-bottom: 26px;
}

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

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

.category-card,
.feature-card,
.scenario-card,
.info-card,
.faq-item,
.tip-card,
.step,
.panel-card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: 0 12px 34px rgba(39,94,160,0.07);
}

.category-card {
    padding: 20px;
    transition: transform .2s ease, border-color .2s ease;
}

.category-card:hover {
    transform: translateY(-3px);
    border-color: rgba(70,139,223,0.36);
}

.category-card span {
    display: inline-flex;
    width: 34px;
    height: 34px;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 900;
    margin-bottom: 10px;
}

.category-card p,
.feature-card p,
.scenario-card p,
.info-card p,
.tip-card p,
.panel-card p,
.step p,
.faq-item p {
    color: var(--muted);
    margin: 0;
}

.feature-card,
.scenario-card,
.info-card,
.tip-card,
.panel-card {
    padding: 22px;
}

.feature-icon {
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    background: linear-gradient(135deg, rgba(70,139,223,0.16), rgba(70,139,223,0.05));
    color: var(--primary-dark);
    font-weight: 900;
    margin-bottom: 12px;
}

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

.security-panel {
    padding: 24px;
    border-radius: 28px;
    background: linear-gradient(145deg, rgba(255,255,255,0.9), rgba(230,243,255,0.92));
    border: 1px solid rgba(70,139,223,0.18);
    box-shadow: var(--shadow);
}

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

.security-list li,
.clean-list li {
    padding: 12px 14px;
    border-radius: 15px;
    background: rgba(255,255,255,0.74);
    border: 1px solid rgba(70,139,223,0.12);
    color: var(--muted);
}

.steps {
    display: grid;
    gap: 14px;
    counter-reset: step;
}

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

.step::before {
    counter-increment: step;
    content: counter(step);
    display: inline-grid;
    place-items: center;
    width: 34px;
    height: 34px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    font-weight: 900;
    margin-bottom: 12px;
}

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

.faq-item {
    padding: 20px;
}

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

.cta-section {
    margin: 42px 0 0;
    padding: 34px 22px;
    text-align: center;
    border-radius: 30px;
    background: linear-gradient(135deg, rgba(70,139,223,0.14), rgba(255,255,255,0.92));
    border: 1px solid rgba(70,139,223,0.18);
    box-shadow: var(--shadow);
}

.cta-section p {
    max-width: 680px;
    margin: 0 auto 20px;
    color: var(--muted);
}

.page-hero {
    padding: 50px 0 28px;
}

.page-hero-card {
    padding: 30px 22px;
    border-radius: 30px;
    background: linear-gradient(135deg, rgba(255,255,255,0.9), rgba(231,244,255,0.88));
    border: 1px solid rgba(70,139,223,0.18);
    box-shadow: var(--shadow);
}

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

.article-section {
    padding-top: 24px;
}

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

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

.note-panel {
    border-left: 4px solid var(--primary);
    background: var(--primary-soft);
    padding: 18px;
    border-radius: 16px;
    color: var(--primary-dark);
    margin: 20px 0;
}

.download-panel {
    margin-top: 22px;
    padding: 22px;
    border-radius: 24px;
    background: linear-gradient(135deg, #fff, var(--blue-100));
    border: 1px solid var(--line);
}

.matrix {
    display: grid;
    gap: 14px;
}

.matrix .panel-card:nth-child(2n) {
    background: rgba(236,246,255,0.86);
}

.site-footer {
    margin-top: 40px;
    background: linear-gradient(180deg, rgba(236,246,255,0.86), rgba(255,255,255,0.98));
    border-top: 1px solid rgba(70,139,223,0.16);
    padding: 38px 0 0;
}

.footer-grid {
    display: grid;
    gap: 24px;
}

.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.footer-brand img {
    width: 34px;
    height: 34px;
    border-radius: 10px;
}

.site-footer p,
.site-footer a {
    color: var(--muted);
    font-size: 14px;
}

.site-footer a {
    display: block;
    margin: 8px 0;
}

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

.footer-bottom {
    margin-top: 30px;
    padding: 18px;
    text-align: center;
    color: var(--muted);
    font-size: 13px;
    border-top: 1px solid rgba(70,139,223,0.12);
}

@media (min-width: 640px) {
    .trust-grid,
    .category-grid,
    .feature-grid,
    .scenario-grid,
    .info-grid,
    .related-grid,
    .matrix {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .page-hero-card,
    .article-card {
        padding: 34px;
    }
}

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

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

    .site-nav a {
        padding: 9px 12px;
    }

    .hero {
        padding-top: 78px;
    }

    .hero-layout,
    .security-layout,
    .split-layout,
    .guide-layout {
        grid-template-columns: minmax(0, 1.05fr) minmax(360px, .95fr);
    }

    .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));
    }

    .footer-grid {
        grid-template-columns: 1.3fr .8fr .8fr .8fr;
    }

    .article-card {
        padding: 42px;
    }
}

@media (min-width: 1120px) {
    section {
        padding: 68px 0;
    }

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

    .app-shot {
        width: 310px;
    }
}