* {
    box-sizing: border-box;
}

:root {
    --primary: rgb(70,139,223);
    --primary-dark: #245a9d;
    --primary-soft: #e8f2ff;
    --ink: #152238;
    --muted: #65758b;
    --line: #dbe8f8;
    --card: rgba(255,255,255,.86);
    --bg: #f6faff;
    --shadow: 0 18px 50px rgba(35, 96, 165, .12);
    --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:
        radial-gradient(circle at 12% 8%, rgba(70,139,223,.18), transparent 26rem),
        radial-gradient(circle at 90% 20%, rgba(145,190,244,.28), transparent 30rem),
        linear-gradient(180deg, #f7fbff 0%, #eef6ff 48%, #ffffff 100%);
    line-height: 1.72;
    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: 30;
    background: rgba(255, 255, 255, .82);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(219,232,248,.82);
}

.header-inner {
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.logo, .footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: -.02em;
    color: #10233f;
}

.logo img, .footer-logo img {
    border-radius: 12px;
    box-shadow: 0 10px 24px rgba(70,139,223,.22);
}

.nav-toggle {
    width: 44px;
    height: 44px;
    border: 1px solid var(--line);
    background: #fff;
    border-radius: 14px;
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
}

.nav-toggle span {
    width: 20px;
    height: 2px;
    border-radius: 10px;
    background: var(--primary-dark);
}

.main-nav {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 76px;
    display: none;
    flex-direction: column;
    gap: 8px;
    padding: 14px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: var(--shadow);
}

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

.main-nav a {
    padding: 12px 14px;
    border-radius: 14px;
    color: #334155;
    font-weight: 650;
}

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

main {
    min-height: 60vh;
}

.section {
    padding: 54px 0;
}

.section-tight {
    padding: 34px 0;
}

.section-title {
    margin: 0 0 14px;
    font-size: clamp(28px, 4vw, 44px);
    line-height: 1.16;
    letter-spacing: -.04em;
}

.section-lead {
    margin: 0;
    color: var(--muted);
    font-size: 17px;
    max-width: 760px;
}

.hero {
    padding: 54px 0 38px;
}

.hero-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 28px;
    align-items: center;
}

.hero-copy {
    padding: 24px 0;
}

.eyebrow, .badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--primary-dark);
    background: rgba(70,139,223,.1);
    border: 1px solid rgba(70,139,223,.2);
    border-radius: 999px;
    padding: 7px 12px;
    font-size: 13px;
    font-weight: 750;
}

h1 {
    font-size: clamp(34px, 8vw, 64px);
    line-height: 1.05;
    letter-spacing: -.055em;
    margin: 18px 0 18px;
}

.hero p {
    color: #42526b;
    font-size: 18px;
    margin: 0 0 22px;
    max-width: 680px;
}

.hero-tags, .tag-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 18px 0 26px;
}

.tag, .mini-tag {
    display: inline-flex;
    align-items: center;
    border-radius: 999px;
    background: #fff;
    border: 1px solid var(--line);
    color: #375071;
    padding: 8px 12px;
    font-size: 13px;
    font-weight: 700;
    box-shadow: 0 10px 26px rgba(70,139,223,.08);
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 13px 24px;
    border-radius: 999px;
    background: linear-gradient(135deg, var(--primary), #2d7bdc);
    color: #fff;
    font-weight: 800;
    letter-spacing: .01em;
    box-shadow: 0 16px 36px rgba(70,139,223,.28);
    border: 0;
    cursor: pointer;
    transition: transform .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 20px 42px rgba(70,139,223,.34);
}

.hero-visual {
    position: relative;
    min-height: 470px;
    border-radius: 30px;
    padding: 24px;
    background: linear-gradient(145deg, rgba(255,255,255,.94), rgba(232,242,255,.82));
    border: 1px solid rgba(255,255,255,.78);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.hero-visual::before {
    content: "";
    position: absolute;
    width: 270px;
    height: 270px;
    border-radius: 50%;
    background: rgba(70,139,223,.16);
    right: -80px;
    top: -80px;
}

.phone-wrap {
    position: relative;
    width: min(76%, 310px);
    margin: 16px auto 0;
    z-index: 1;
}

.floating-card,
.security-status,
.asset-chip {
    position: absolute;
    z-index: 2;
    background: rgba(255,255,255,.9);
    border: 1px solid rgba(219,232,248,.88);
    box-shadow: 0 16px 34px rgba(47,97,157,.13);
    border-radius: 18px;
    padding: 12px 14px;
}

.security-status {
    top: 26px;
    left: 18px;
    max-width: 210px;
}

.security-status strong,
.floating-card strong {
    display: block;
    color: #17345c;
    font-size: 14px;
}

.security-status span,
.floating-card span {
    color: var(--muted);
    font-size: 12px;
}

.floating-card.one {
    right: 16px;
    top: 150px;
}

.floating-card.two {
    left: 18px;
    bottom: 34px;
}

.asset-chip {
    right: 24px;
    bottom: 100px;
    color: var(--primary-dark);
    font-weight: 800;
    font-size: 13px;
}

.trust-strip {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}

.trust-item {
    background: rgba(255,255,255,.78);
    border: 1px solid var(--line);
    border-radius: 20px;
    padding: 18px;
    box-shadow: 0 12px 32px rgba(70,139,223,.08);
}

.trust-item strong {
    display: block;
    color: #183a64;
    font-size: 18px;
    margin-bottom: 4px;
}

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

.category-grid,
.feature-grid,
.scenario-grid,
.article-grid,
.download-grid,
.tip-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 18px;
    margin-top: 24px;
}

.category-card,
.feature-card,
.scenario-card,
.article-card,
.tip-card,
.faq-item,
.info-panel,
.step-card,
.warning-panel {
    background: var(--card);
    border: 1px solid rgba(219,232,248,.88);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: 0 14px 34px rgba(70,139,223,.08);
}

.category-card {
    display: flex;
    flex-direction: column;
    min-height: 190px;
    transition: transform .2s ease, border-color .2s ease;
}

.category-card:hover {
    transform: translateY(-4px);
    border-color: rgba(70,139,223,.42);
}

.category-card h3,
.feature-card h3,
.scenario-card h3,
.article-card h2,
.tip-card h3,
.info-panel h2,
.step-card h3 {
    margin: 0 0 10px;
    color: #15365f;
    line-height: 1.25;
}

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

.card-link {
    margin-top: auto;
    padding-top: 16px;
    color: var(--primary-dark);
    font-weight: 800;
}

.two-column,
.security-layout,
.content-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
    align-items: start;
}

.security-panel {
    position: relative;
    overflow: hidden;
    border-radius: 28px;
    padding: 26px;
    background: linear-gradient(145deg, #ffffff, #eaf4ff);
    border: 1px solid rgba(219,232,248,.92);
    box-shadow: var(--shadow);
}

.security-panel::after {
    content: "";
    position: absolute;
    width: 180px;
    height: 180px;
    right: -50px;
    bottom: -70px;
    border-radius: 50%;
    background: rgba(70,139,223,.12);
}

.security-row {
    position: relative;
    z-index: 1;
    display: flex;
    justify-content: space-between;
    gap: 16px;
    padding: 14px 0;
    border-bottom: 1px solid var(--line);
}

.security-row:last-child {
    border-bottom: 0;
}

.security-row span {
    color: var(--muted);
}

.security-row strong {
    color: #15365f;
}

.steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 16px;
    margin-top: 24px;
}

.step-number {
    width: 38px;
    height: 38px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 900;
    margin-bottom: 14px;
}

.cta-section {
    text-align: center;
    border-radius: 30px;
    padding: 38px 22px;
    background: linear-gradient(135deg, rgba(70,139,223,.12), rgba(255,255,255,.9));
    border: 1px solid rgba(219,232,248,.96);
    box-shadow: var(--shadow);
}

.cta-section h2 {
    margin: 0 0 12px;
    font-size: clamp(26px, 4vw, 42px);
    letter-spacing: -.035em;
}

.cta-section p {
    color: var(--muted);
    margin: 0 auto 22px;
    max-width: 720px;
}

.page-hero {
    padding: 52px 0 24px;
}

.page-hero-inner {
    border-radius: 30px;
    padding: 28px;
    background: linear-gradient(135deg, rgba(255,255,255,.88), rgba(230,242,255,.76));
    border: 1px solid rgba(219,232,248,.92);
    box-shadow: var(--shadow);
}

.page-hero h1 {
    max-width: 880px;
    margin-bottom: 16px;
}

.page-hero p {
    max-width: 800px;
    color: var(--muted);
    font-size: 17px;
}

.article-card ul,
.info-panel ul,
.warning-panel ul,
.faq-list ul,
.tip-card ul {
    padding-left: 20px;
    margin: 12px 0 0;
    color: var(--muted);
}

.article-card li,
.info-panel li,
.warning-panel li,
.tip-card li {
    margin: 6px 0;
}

.faq-list {
    display: grid;
    gap: 16px;
    margin-top: 24px;
}

.faq-item h2,
.faq-item h3 {
    margin: 0 0 8px;
    color: #15365f;
    font-size: 20px;
}

.warning-panel {
    background: linear-gradient(135deg, #fff, #f2f8ff);
}

.download-grid {
    align-items: stretch;
}

.download-card-main {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 26px;
    box-shadow: var(--shadow);
}

.download-card-main .download-btn {
    margin-top: 18px;
}

.site-footer {
    margin-top: 52px;
    padding: 42px 0 20px;
    background: linear-gradient(180deg, rgba(241,247,255,.96), #ffffff);
    border-top: 1px solid var(--line);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

.site-footer p {
    color: var(--muted);
    max-width: 520px;
}

.site-footer h3 {
    margin: 0 0 10px;
    color: #15365f;
    font-size: 16px;
}

.site-footer a {
    display: block;
    color: #53677f;
    margin: 8px 0;
}

.footer-bottom {
    margin-top: 30px;
    padding-top: 18px;
    border-top: 1px solid var(--line);
    display: flex;
    flex-direction: column;
    gap: 8px;
    color: #7a8aa0;
    font-size: 13px;
}

@media (min-width: 640px) {
    .container {
        width: min(100% - 44px, 1160px);
    }
    .trust-strip,
    .category-grid,
    .feature-grid,
    .scenario-grid,
    .tip-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
    .article-grid,
    .download-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (min-width: 920px) {
    .nav-toggle {
        display: none;
    }
    .main-nav {
        position: static;
        display: flex;
        flex-direction: row;
        align-items: center;
        gap: 2px;
        padding: 0;
        background: transparent;
        border: 0;
        box-shadow: none;
    }
    .main-nav a {
        font-size: 14px;
        padding: 10px 13px;
    }
    .hero {
        padding: 78px 0 48px;
    }
    .hero-layout {
        grid-template-columns: 1.03fr .97fr;
        gap: 52px;
    }
    .two-column,
    .security-layout,
    .content-layout {
        grid-template-columns: minmax(0, 1.03fr) minmax(320px, .97fr);
        gap: 34px;
    }
    .category-grid,
    .feature-grid,
    .scenario-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
    .trust-strip,
    .steps {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
    .tip-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
    .footer-grid {
        grid-template-columns: 1.4fr .8fr .8fr;
    }
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
    .page-hero-inner {
        padding: 44px;
    }
}

@media (max-width: 420px) {
    .container {
        width: min(100% - 24px, 1160px);
    }
    h1 {
        font-size: 32px;
    }
    .hero-visual {
        min-height: 430px;
        padding: 16px;
    }
    .floating-card.one {
        top: 138px;
    }
    .download-btn {
        width: 100%;
    }
}