:root {
    --primary: rgb(70,139,223);
    --primary-dark: rgb(36, 91, 165);
    --primary-soft: rgb(232, 243, 255);
    --primary-faint: rgb(246, 250, 255);
    --text: #18304f;
    --muted: #61738d;
    --line: rgba(70, 139, 223, 0.18);
    --white: #ffffff;
    --shadow: 0 18px 45px rgba(39, 90, 154, 0.11);
    --radius-lg: 24px;
    --radius-md: 18px;
}

* {
    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 20% 2%, rgba(70,139,223,0.18), transparent 28%),
        linear-gradient(180deg, #eef7ff 0%, #ffffff 42%, #f7fbff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    background-image: linear-gradient(rgba(70,139,223,0.05) 1px, transparent 1px), linear-gradient(90deg, rgba(70,139,223,0.05) 1px, transparent 1px);
    background-size: 34px 34px;
    mask-image: linear-gradient(180deg, rgba(0,0,0,0.65), transparent 70%);
    z-index: -1;
}

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

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

.container {
    width: min(100% - 32px, 1160px);
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255, 255, 255, 0.86);
    backdrop-filter: blur(18px);
    border-bottom: 1px solid var(--line);
}

.header-inner {
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--primary-dark);
    flex: 0 0 auto;
}

.logo {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(70, 139, 223, 0.22);
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 4px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding: 10px 0;
}

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

.main-nav a {
    flex: 0 0 auto;
    padding: 8px 12px;
    border-radius: 999px;
    font-size: 14px;
    color: #405674;
    transition: background 0.2s ease, color 0.2s ease;
}

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

.page-main {
    min-height: 68vh;
}

.hero,
.sub-hero {
    padding: 38px 0 24px;
}

.hero-grid {
    display: grid;
    gap: 26px;
    align-items: center;
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 12px;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: rgba(255,255,255,0.8);
    color: var(--primary-dark);
    font-size: 13px;
    font-weight: 700;
}

h1,
h2,
h3 {
    margin: 0 0 14px;
    line-height: 1.25;
    color: #0f2846;
}

h1 {
    font-size: clamp(32px, 8vw, 58px);
    letter-spacing: -0.055em;
    margin-top: 16px;
}

h2 {
    font-size: clamp(24px, 5vw, 38px);
    letter-spacing: -0.035em;
}

h3 {
    font-size: 18px;
}

p {
    margin: 0 0 14px;
    color: var(--muted);
}

.lead {
    font-size: 17px;
    color: #4e6582;
    max-width: 700px;
}

.hero-actions {
    margin: 22px 0 0;
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 22px;
    border-radius: 999px;
    border: 0;
    background: var(--primary);
    color: #fff;
    font-size: 16px;
    font-weight: 800;
    letter-spacing: 0.01em;
    box-shadow: 0 14px 28px rgba(70, 139, 223, 0.28);
    cursor: pointer;
    transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.download-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 18px 36px rgba(70, 139, 223, 0.32);
}

.hero-note {
    font-size: 13px;
    color: var(--muted);
}

.badge-row {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 22px;
}

.badge {
    display: inline-flex;
    align-items: center;
    padding: 8px 11px;
    border-radius: 999px;
    background: rgba(70,139,223,0.1);
    border: 1px solid rgba(70,139,223,0.16);
    color: #245a9f;
    font-size: 13px;
    font-weight: 700;
}

.hero-visual {
    position: relative;
    min-height: 330px;
    display: grid;
    place-items: center;
}

.device-card {
    width: min(88%, 420px);
    border-radius: 34px;
    padding: 18px;
    background: linear-gradient(145deg, rgba(255,255,255,0.95), rgba(229,243,255,0.9));
    box-shadow: var(--shadow);
    border: 1px solid rgba(255,255,255,0.9);
}

.device-card img {
    border-radius: 28px;
    width: 100%;
    box-shadow: 0 18px 40px rgba(22, 69, 126, 0.16);
}

.float-card {
    position: absolute;
    right: 6px;
    bottom: 18px;
    width: 170px;
    border-radius: 20px;
    background: rgba(255,255,255,0.92);
    border: 1px solid rgba(70,139,223,0.15);
    box-shadow: 0 16px 35px rgba(39, 90, 154, 0.13);
    padding: 14px;
}

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

.float-card span {
    display: block;
    color: var(--muted);
    font-size: 12px;
    line-height: 1.5;
}

.section {
    padding: 34px 0;
}

.section-head {
    margin-bottom: 20px;
}

.section-head.center {
    text-align: center;
    max-width: 760px;
    margin-left: auto;
    margin-right: auto;
}

.grid,
.feature-grid,
.steps-grid,
.info-grid,
.faq-grid {
    display: grid;
    gap: 16px;
}

.card,
.feature-card,
.info-card,
.faq-item,
.step-card,
.notice-card,
.content-panel {
    background: rgba(255,255,255,0.88);
    border: 1px solid rgba(70,139,223,0.12);
    border-radius: var(--radius-lg);
    padding: 20px;
    box-shadow: 0 12px 35px rgba(39, 90, 154, 0.08);
}

.feature-card {
    background: linear-gradient(180deg, #ffffff, #f5faff);
}

.feature-icon,
.step-num {
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 900;
    margin-bottom: 12px;
}

.content-panel {
    padding: 24px;
}

.content-panel p:last-child,
.card p:last-child,
.feature-card p:last-child,
.info-card p:last-child,
.faq-item p:last-child,
.step-card p:last-child,
.notice-card p:last-child {
    margin-bottom: 0;
}

.split {
    display: grid;
    gap: 18px;
    align-items: center;
}

.stat-row {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
}

.stat {
    padding: 16px;
    border-radius: 18px;
    background: #fff;
    border: 1px solid var(--line);
}

.stat strong {
    display: block;
    color: var(--primary-dark);
    font-size: 22px;
    line-height: 1.1;
}

.stat span {
    display: block;
    margin-top: 4px;
    color: var(--muted);
    font-size: 13px;
}

.faq-item h2,
.faq-item h3 {
    font-size: 17px;
    margin-bottom: 8px;
}

.guide-list,
.clean-list {
    margin: 0;
    padding-left: 20px;
    color: var(--muted);
}

.guide-list li,
.clean-list li {
    margin: 8px 0;
}

.cta-panel {
    border-radius: 28px;
    background: linear-gradient(135deg, rgba(70,139,223,0.95), rgba(42,106,190,0.92));
    color: #fff;
    padding: 26px;
    box-shadow: 0 20px 45px rgba(70,139,223,0.26);
}

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

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

.cta-panel .download-btn:hover {
    background: #edf6ff;
}

.sub-hero .content-panel {
    background: linear-gradient(145deg, rgba(255,255,255,0.95), rgba(241,248,255,0.96));
}

.site-footer {
    margin-top: 36px;
    padding: 36px 0 22px;
    background: #102a47;
    color: rgba(255,255,255,0.82);
}

.site-footer h2 {
    font-size: 16px;
    color: #fff;
    margin-bottom: 10px;
}

.footer-brand {
    font-size: 20px;
    font-weight: 900;
    color: #fff;
    margin-bottom: 10px;
}

.site-footer p {
    color: rgba(255,255,255,0.68);
}

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

.site-footer a {
    display: block;
    color: rgba(255,255,255,0.68);
    font-size: 14px;
    margin: 8px 0;
}

.footer-bottom {
    margin-top: 28px;
    padding-top: 18px;
    border-top: 1px solid rgba(255,255,255,0.12);
    display: flex;
    gap: 8px;
    flex-direction: column;
    font-size: 13px;
    color: rgba(255,255,255,0.58);
}

@media (min-width: 680px) {
    .container {
        width: min(100% - 56px, 1160px);
    }
    .hero,
    .sub-hero {
        padding: 56px 0 34px;
    }
    .feature-grid,
    .steps-grid,
    .info-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
    .faq-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
    .stat-row {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
    .footer-grid {
        grid-template-columns: 1.4fr 1fr 1fr;
    }
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
}

@media (min-width: 960px) {
    .header-inner {
        min-height: 78px;
    }
    .main-nav {
        overflow: visible;
        gap: 8px;
    }
    .main-nav a {
        padding: 9px 14px;
    }
    .hero-grid,
    .split {
        grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.95fr);
    }
    .hero {
        padding: 78px 0 46px;
    }
    .section {
        padding: 52px 0;
    }
    .feature-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
    .steps-grid,
    .info-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
    .content-panel,
    .card,
    .feature-card,
    .info-card,
    .faq-item,
    .step-card,
    .notice-card {
        padding: 26px;
    }
    .cta-panel {
        padding: 36px;
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 24px;
    }
    .cta-panel p {
        max-width: 720px;
    }
}