* {
    box-sizing: border-box;
}

:root {
    --primary: rgb(70,139,223);
    --primary-dark: #275fba;
    --primary-soft: #eaf4ff;
    --primary-light: #f5faff;
    --text: #102033;
    --muted: #607089;
    --line: #dce9f8;
    --white: #ffffff;
    --shadow: 0 16px 40px rgba(35, 86, 153, 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(--text);
    background: linear-gradient(180deg, #f4f9ff 0%, #ffffff 44%, #f7fbff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}

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

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

.container {
    width: min(100% - 32px, 1180px);
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.88);
    backdrop-filter: blur(18px);
    border-bottom: 1px solid rgba(70, 139, 223, 0.12);
}

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

.brand,
.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: #14345d;
    letter-spacing: 0.02em;
}

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

.nav-toggle {
    width: 44px;
    height: 44px;
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    border: 0;
    border-radius: 14px;
    background: var(--primary-soft);
    cursor: pointer;
}

.nav-toggle span {
    width: 20px;
    height: 2px;
    background: var(--primary-dark);
    border-radius: 4px;
}

.site-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 76px;
    display: none;
    padding: 14px;
    background: var(--white);
    border: 1px solid var(--line);
    border-radius: 20px;
    box-shadow: var(--shadow);
}

.site-nav.open {
    display: grid;
    gap: 6px;
}

.site-nav a {
    padding: 11px 14px;
    color: #36506d;
    border-radius: 14px;
    font-size: 15px;
}

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

.hero,
.page-hero {
    padding: 56px 0 34px;
}

.hero-grid {
    display: grid;
    gap: 28px;
    align-items: center;
}

.kicker,
.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 12px;
    border-radius: 999px;
    background: rgba(70,139,223,0.11);
    color: var(--primary-dark);
    font-size: 13px;
    font-weight: 700;
}

h1,
h2,
h3 {
    margin: 0 0 14px;
    line-height: 1.25;
    color: #102947;
}

h1 {
    font-size: clamp(30px, 7vw, 58px);
    letter-spacing: -0.04em;
}

h2 {
    font-size: clamp(24px, 4vw, 36px);
    letter-spacing: -0.025em;
}

h3 {
    font-size: 20px;
}

p {
    margin: 0 0 16px;
    color: var(--muted);
}

.hero p,
.page-hero p {
    font-size: 17px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
    margin: 24px 0;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 24px;
    border-radius: 999px;
    background: var(--primary);
    color: var(--white);
    font-weight: 800;
    box-shadow: 0 14px 28px rgba(70,139,223,0.24);
    border: 1px solid rgba(70,139,223,0.08);
    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(70,139,223,0.28);
}

.trust-tags,
.stat-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 18px;
}

.trust-tags span,
.stat-card {
    padding: 9px 12px;
    border-radius: 999px;
    background: var(--white);
    border: 1px solid var(--line);
    color: #42607e;
    font-size: 13px;
    box-shadow: 0 8px 20px rgba(70,139,223,0.08);
}

.product-visual {
    position: relative;
    padding: 18px;
    border-radius: 30px;
    background: linear-gradient(135deg, rgba(70,139,223,0.18), rgba(255,255,255,0.88));
    border: 1px solid rgba(70,139,223,0.18);
    box-shadow: var(--shadow);
}

.product-visual::after {
    content: "本地密钥 · 风险提醒";
    position: absolute;
    right: 18px;
    bottom: 18px;
    padding: 8px 12px;
    border-radius: 999px;
    background: rgba(255,255,255,0.92);
    color: var(--primary-dark);
    font-size: 13px;
    font-weight: 700;
    box-shadow: 0 12px 24px rgba(70,139,223,0.14);
}

.section {
    padding: 42px 0;
}

.section-head {
    max-width: 760px;
    margin-bottom: 24px;
}

.card,
.info-card,
.faq-item,
.step-card {
    background: var(--white);
    border: 1px solid rgba(70,139,223,0.12);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.card,
.info-card,
.step-card {
    padding: 22px;
}

.feature-grid,
.card-grid,
.step-grid,
.faq-grid {
    display: grid;
    gap: 16px;
}

.card .icon,
.step-num {
    width: 44px;
    height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 15px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 900;
    margin-bottom: 14px;
}

.panel {
    padding: 26px;
    border-radius: 28px;
    background: linear-gradient(135deg, rgba(70,139,223,0.12), rgba(255,255,255,0.88));
    border: 1px solid rgba(70,139,223,0.14);
}

.split {
    display: grid;
    gap: 20px;
}

.check-list,
.clean-list {
    padding: 0;
    margin: 12px 0 0;
    list-style: none;
    display: grid;
    gap: 10px;
}

.check-list li,
.clean-list li {
    position: relative;
    padding-left: 28px;
    color: #526880;
}

.check-list li::before,
.clean-list li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 10px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--primary);
    box-shadow: 0 0 0 5px rgba(70,139,223,0.12);
}

.faq-item {
    padding: 20px;
}

.faq-item h2,
.faq-item h3 {
    font-size: 18px;
    margin-bottom: 8px;
}

.cta-box {
    padding: 28px;
    border-radius: 30px;
    background: linear-gradient(135deg, var(--primary), #8dbdff);
    color: var(--white);
    box-shadow: 0 20px 46px rgba(70,139,223,0.24);
}

.cta-box h2,
.cta-box p {
    color: var(--white);
}

.cta-box .download-btn {
    background: var(--white);
    color: var(--primary-dark);
    box-shadow: none;
}

.article {
    max-width: 900px;
}

.article .download-btn {
    margin-top: 10px;
}

.notice {
    padding: 18px;
    border-radius: 20px;
    background: #f2f8ff;
    border: 1px solid var(--line);
    color: #405c79;
    margin: 18px 0;
}

.site-footer {
    margin-top: 40px;
    padding: 42px 0 22px;
    background: #102947;
    color: rgba(255,255,255,0.82);
}

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

.site-footer p,
.site-footer a {
    color: rgba(255,255,255,0.72);
}

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

.site-footer h3,
.footer-brand {
    color: var(--white);
}

.footer-bottom {
    margin-top: 28px;
    padding-top: 18px;
    border-top: 1px solid rgba(255,255,255,0.12);
    font-size: 14px;
    color: rgba(255,255,255,0.58);
}

@media (min-width: 720px) {
    .container {
        width: min(100% - 56px, 1180px);
    }

    .hero,
    .page-hero {
        padding: 76px 0 46px;
    }

    .feature-grid,
    .card-grid,
    .step-grid,
    .faq-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 20px;
    }

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

@media (min-width: 980px) {
    .nav-toggle {
        display: none;
    }

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

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

    .hero-grid,
    .split {
        grid-template-columns: 1.05fr .95fr;
    }

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

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

    .section {
        padding: 58px 0;
    }
}