:root {
    --primary: rgb(70,139,223);
    --primary-dark: rgb(39, 91, 158);
    --primary-soft: rgb(232, 243, 255);
    --primary-light: rgb(244, 249, 255);
    --text: rgb(24, 39, 62);
    --muted: rgb(93, 111, 137);
    --line: rgba(70, 139, 223, 0.16);
    --card: rgba(255, 255, 255, 0.92);
    --shadow: 0 14px 38px rgba(39, 91, 158, 0.10);
    --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(--text);
    background:
        radial-gradient(circle at 12% 0%, rgba(70,139,223,0.20), transparent 30%),
        linear-gradient(180deg, #f8fbff 0%, #edf6ff 42%, #ffffff 100%);
    line-height: 1.75;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    background-image: linear-gradient(rgba(70,139,223,0.04) 1px, transparent 1px), linear-gradient(90deg, rgba(70,139,223,0.04) 1px, transparent 1px);
    background-size: 28px 28px;
    mask-image: linear-gradient(180deg, rgba(0,0,0,0.85), transparent 70%);
}

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

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

.site-shell {
    width: 100%;
    max-width: 720px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    padding: 14px 16px 10px;
    background: rgba(248, 251, 255, 0.88);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(70,139,223,0.10);
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: 0.2px;
    color: var(--primary-dark);
    margin-bottom: 12px;
}

.logo {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(70,139,223,0.18);
}

.mobile-nav {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 2px;
    scrollbar-width: none;
}

.mobile-nav::-webkit-scrollbar {
    display: none;
}

.mobile-nav a {
    flex: 0 0 auto;
    padding: 8px 13px;
    border: 1px solid rgba(70,139,223,0.14);
    border-radius: 999px;
    background: rgba(255,255,255,0.72);
    color: var(--muted);
    font-size: 14px;
    line-height: 1;
}

.mobile-nav a.active,
.mobile-nav a:focus {
    color: #fff;
    background: var(--primary);
    border-color: var(--primary);
}

main {
    padding: 16px;
}

.banner,
.page-hero,
.download-hero {
    position: relative;
    overflow: hidden;
    border-radius: 28px;
    padding: 24px;
    background: linear-gradient(145deg, #ffffff 0%, #eef7ff 55%, #ffffff 100%);
    box-shadow: var(--shadow);
    border: 1px solid rgba(70,139,223,0.14);
}

.banner::after,
.page-hero::after,
.download-hero::after {
    content: "";
    position: absolute;
    width: 180px;
    height: 180px;
    border-radius: 50%;
    right: -70px;
    top: -60px;
    background: radial-gradient(circle, rgba(70,139,223,0.20), transparent 70%);
}

.banner-content,
.page-hero-content,
.download-hero-content {
    position: relative;
    z-index: 2;
}

.eyebrow,
.badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 10px;
    border-radius: 999px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.2px;
    border: 1px solid rgba(70,139,223,0.14);
}

h1,
h2,
h3 {
    color: rgb(18, 37, 66);
    line-height: 1.25;
    margin: 0;
}

h1 {
    font-size: clamp(28px, 8vw, 42px);
    letter-spacing: -0.8px;
    margin-top: 14px;
}

h2 {
    font-size: 23px;
    margin-bottom: 12px;
}

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

p {
    margin: 10px 0 0;
    color: var(--muted);
    font-size: 15.5px;
}

.lead {
    color: rgb(57, 76, 103);
    font-size: 16.5px;
    margin-top: 14px;
}

.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;
    border: 0;
    box-shadow: 0 12px 24px rgba(70,139,223,0.28);
    margin-top: 20px;
    letter-spacing: 0.2px;
}

.download-btn::after {
    content: "›";
    margin-left: 8px;
    font-size: 20px;
    line-height: 1;
}

.hero-device {
    margin-top: 20px;
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}

.app-preview {
    width: min(72vw, 320px);
    margin: 0 auto;
    filter: drop-shadow(0 26px 42px rgba(39,91,158,0.20));
}

.security-tags,
.inline-tags {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: 16px;
}

.security-tags span,
.inline-tags span {
    padding: 8px 11px;
    border-radius: 999px;
    background: rgba(255,255,255,0.82);
    color: var(--primary-dark);
    font-size: 12.5px;
    font-weight: 700;
    border: 1px solid rgba(70,139,223,0.15);
}

section {
    margin-top: 22px;
}

.section-head {
    margin-bottom: 14px;
}

.card,
.info-card,
.faq-item,
.step-card,
.notice-card,
.stat-card {
    background: var(--card);
    border: 1px solid rgba(70,139,223,0.12);
    border-radius: var(--radius);
    box-shadow: 0 10px 28px rgba(39,91,158,0.08);
}

.card,
.info-card,
.notice-card {
    padding: 18px;
}

.card + .card,
.info-card + .info-card,
.notice-card + .notice-card,
.faq-item + .faq-item,
.step-card + .step-card {
    margin-top: 12px;
}

.feature-grid,
.card-grid,
.stats-grid,
.link-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
}

.feature-card {
    padding: 18px;
    border-radius: var(--radius);
    background: linear-gradient(180deg, #ffffff, var(--primary-light));
    border: 1px solid rgba(70,139,223,0.13);
    box-shadow: 0 10px 24px rgba(39,91,158,0.07);
}

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

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

.stat-card {
    padding: 16px;
}

.stat-card strong {
    display: block;
    color: var(--primary-dark);
    font-size: 20px;
}

.stat-card span {
    color: var(--muted);
    font-size: 13px;
}

.faq-item {
    padding: 16px;
}

.faq-item h3 {
    font-size: 16.5px;
}

.step-list {
    counter-reset: step;
    display: grid;
    gap: 12px;
}

.step-card {
    position: relative;
    padding: 16px 16px 16px 58px;
}

.step-card::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 16px;
    top: 18px;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
}

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

.guide-list li {
    padding: 12px 14px;
    border-radius: 16px;
    background: rgba(232,243,255,0.72);
    color: rgb(46, 65, 91);
    border: 1px solid rgba(70,139,223,0.12);
}

.link-card {
    display: block;
    padding: 16px;
    border-radius: var(--radius);
    background: rgba(255,255,255,0.84);
    border: 1px solid rgba(70,139,223,0.12);
}

.link-card strong {
    display: block;
    color: rgb(18, 37, 66);
}

.link-card span {
    display: block;
    color: var(--muted);
    margin-top: 4px;
    font-size: 14px;
}

.cta-section {
    padding: 22px;
    border-radius: 28px;
    background: linear-gradient(135deg, var(--primary), rgb(114, 174, 238));
    color: #fff;
    box-shadow: 0 18px 36px rgba(70,139,223,0.25);
}

.cta-section h2,
.cta-section p {
    color: #fff;
}

.cta-section .download-btn {
    background: #fff;
    color: var(--primary-dark);
    box-shadow: 0 10px 22px rgba(20,40,80,0.12);
}

.download-note {
    margin-top: 12px;
    font-size: 13px;
    color: rgba(255,255,255,0.88);
}

.site-footer {
    padding: 24px 16px 32px;
    margin-top: 18px;
    color: var(--muted);
    border-top: 1px solid rgba(70,139,223,0.12);
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--primary-dark);
}

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

.footer-links {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 14px;
}

.footer-links a {
    color: var(--primary-dark);
    font-size: 13px;
    padding: 6px 9px;
    border-radius: 999px;
    background: rgba(232,243,255,0.7);
}

.copyright {
    font-size: 12px;
    margin-top: 16px;
}

.desktop-notice {
    position: fixed;
    inset: 0;
    z-index: 999;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    background: rgba(246, 251, 255, 0.88);
    backdrop-filter: blur(12px);
}

.desktop-notice-card {
    width: min(440px, 92vw);
    padding: 28px;
    text-align: center;
    border-radius: 28px;
    background: #fff;
    border: 1px solid rgba(70,139,223,0.16);
    box-shadow: var(--shadow);
}

.desktop-notice-logo {
    width: 54px;
    height: 54px;
    border-radius: 16px;
    margin: 0 auto 14px;
}

.device-desktop .site-shell {
    opacity: 0.08;
    pointer-events: none;
    filter: blur(2px);
}

.device-desktop .download-btn {
    display: none !important;
}

@media (min-width: 560px) {
    .feature-grid,
    .card-grid,
    .link-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
    .hero-device {
        grid-template-columns: 1fr 0.9fr;
        align-items: center;
    }
}