/* 来单啦官网样式 —— 与 App 品牌色一致（Primary #2E7DF6） */
:root {
    --primary: #2E7DF6;
    --primary-dark: #1E63D8;
    --primary-soft: #EAF2FE;
    --primary-soft-stroke: #C9E2FF;
    --success: #12B76A;
    --warning: #F79009;
    --danger: #E5484D;
    --text: #1A1D23;
    --sub-text: #6B7280;
    --tertiary-text: #9AA1AC;
    --page-bg: #F5F7FA;
    --card-bg: #FFFFFF;
    --border-light: #EDF0F5;
    --footer-bg: #101828;
    --radius: 16px;
    --shadow: 0 4px 24px rgba(16, 24, 40, 0.06);
    --shadow-lg: 0 12px 40px rgba(46, 125, 246, 0.16);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 80px; }

body {
    font-family: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Segoe UI", sans-serif;
    color: var(--text);
    background: var(--card-bg);
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }

.container { max-width: 1120px; margin: 0 auto; padding: 0 24px; }

/* ============ 顶部导航 ============ */
.site-header {
    position: sticky; top: 0; z-index: 100;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-light);
}

.nav-bar {
    display: flex; align-items: center; justify-content: space-between;
    height: 64px;
}

.brand { display: flex; align-items: center; gap: 10px; font-size: 20px; font-weight: 700; }
.brand svg { width: 32px; height: 32px; }

.nav-menu { display: flex; align-items: center; gap: 28px; list-style: none; }
.nav-menu a { font-size: 15px; color: var(--sub-text); transition: color 0.2s; }
.nav-menu a:hover { color: var(--primary); }
.nav-menu .btn-nav {
    background: var(--primary); color: #fff; padding: 8px 20px;
    border-radius: 999px; font-weight: 600;
}
.nav-menu .btn-nav:hover { background: var(--primary-dark); color: #fff; }

.nav-toggle, .nav-burger { display: none; }

/* ============ Hero ============ */
.hero {
    background: linear-gradient(180deg, #F0F6FF 0%, #FFFFFF 100%);
    padding: 88px 0 72px;
}

.hero-grid {
    display: grid; grid-template-columns: 1.05fr 0.95fr;
    gap: 56px; align-items: center;
}

.hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    background: var(--primary-soft); border: 1px solid var(--primary-soft-stroke);
    color: var(--primary-dark); font-size: 13px; font-weight: 600;
    padding: 6px 14px; border-radius: 999px; margin-bottom: 20px;
}

.hero h1 {
    font-size: clamp(30px, 4.6vw, 48px);
    line-height: 1.28; font-weight: 800; letter-spacing: -0.5px;
}

.hero h1 .accent { color: var(--primary); }

.hero-sub {
    margin-top: 18px; font-size: 18px; color: var(--sub-text);
    max-width: 34em;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 32px; }

.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 13px 30px; border-radius: 12px; font-size: 16px;
    font-weight: 600; transition: all 0.2s; cursor: pointer; border: none;
}

.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 8px 20px rgba(46, 125, 246, 0.28); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); }
.btn-ghost { background: #fff; color: var(--text); border: 1px solid var(--border-light); }
.btn-ghost:hover { border-color: var(--primary); color: var(--primary); }

.hero-notes { display: flex; flex-wrap: wrap; gap: 20px; margin-top: 26px; font-size: 13.5px; color: var(--tertiary-text); }
.hero-notes span { display: inline-flex; align-items: center; gap: 6px; }
.hero-notes .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--success); }

/* Hero 手机 SVG 画框 */
.hero-visual { display: flex; justify-content: center; }
.phone-frame {
    width: min(320px, 100%);
    filter: drop-shadow(0 24px 48px rgba(46, 125, 246, 0.22));
}

/* ============ 通用板块 ============ */
.section { padding: 80px 0; }
.section-alt { background: var(--page-bg); }

.section-head { text-align: center; max-width: 640px; margin: 0 auto 48px; }
.section-head .eyebrow {
    display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 2px;
    color: var(--primary); text-transform: uppercase; margin-bottom: 10px;
}
.section-head h2 { font-size: clamp(26px, 3.4vw, 34px); font-weight: 800; line-height: 1.35; }
.section-head p { margin-top: 14px; color: var(--sub-text); font-size: 16.5px; }

/* ============ 功能卡片 ============ */
.feature-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.feature-card {
    background: var(--card-bg); border: 1px solid var(--border-light);
    border-radius: var(--radius); padding: 30px 28px;
    box-shadow: var(--shadow); transition: all 0.25s;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--primary-soft-stroke); }

.feature-icon {
    width: 52px; height: 52px; border-radius: 14px;
    background: var(--primary-soft); color: var(--primary);
    display: flex; align-items: center; justify-content: center; margin-bottom: 18px;
}
.feature-icon svg { width: 28px; height: 28px; }
.feature-icon.green { background: #E7F8F0; color: var(--success); }
.feature-icon.amber { background: #FEF3E2; color: var(--warning); }

.feature-card h3 { font-size: 18.5px; font-weight: 700; margin-bottom: 10px; }
.feature-card p { color: var(--sub-text); font-size: 15px; }

/* ============ 隐私安全带 ============ */
.safety-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
}

.safety-item {
    background: var(--card-bg); border-radius: var(--radius);
    padding: 28px; border: 1px solid var(--border-light);
}
.safety-item .num {
    font-size: 13px; font-weight: 700; color: var(--primary);
    letter-spacing: 1.5px; margin-bottom: 10px;
}
.safety-item h3 { font-size: 17.5px; margin-bottom: 8px; }
.safety-item p { font-size: 14.5px; color: var(--sub-text); }

/* ============ 下载 ============ */
.download-card {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    border-radius: 24px; padding: 56px 48px; color: #fff;
    display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 40px; align-items: center;
    box-shadow: var(--shadow-lg);
}
.download-card h2 { font-size: clamp(24px, 3vw, 32px); font-weight: 800; line-height: 1.4; }
.download-card p { margin-top: 14px; opacity: 0.88; font-size: 16px; }
.download-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 28px; }
.btn-white { background: #fff; color: var(--primary-dark); }
.btn-white:hover { transform: translateY(-1px); box-shadow: 0 10px 24px rgba(0, 0, 0, 0.18); }
.btn-outline-white { background: transparent; color: #fff; border: 1.5px solid rgba(255, 255, 255, 0.6); }
.btn-outline-white:hover { border-color: #fff; background: rgba(255, 255, 255, 0.12); }
.download-meta {
    background: rgba(255, 255, 255, 0.12); border: 1px solid rgba(255, 255, 255, 0.22);
    border-radius: 16px; padding: 24px; font-size: 14px;
}
.download-meta dl { display: grid; grid-template-columns: auto 1fr; gap: 10px 16px; }
.download-meta dt { opacity: 0.75; }
.download-meta dd { font-weight: 600; }

/* ============ FAQ ============ */
.faq-list { max-width: 780px; margin: 0 auto; display: grid; gap: 14px; }
.faq-item {
    background: var(--card-bg); border: 1px solid var(--border-light);
    border-radius: 14px; overflow: hidden;
}
.faq-item summary {
    padding: 20px 24px; font-weight: 600; font-size: 16.5px; cursor: pointer;
    list-style: none; display: flex; justify-content: space-between; align-items: center; gap: 16px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
    content: ""; width: 10px; height: 10px; flex: none;
    border-right: 2px solid var(--tertiary-text); border-bottom: 2px solid var(--tertiary-text);
    transform: rotate(45deg); transition: transform 0.25s; margin-top: -4px;
}
.faq-item[open] summary::after { transform: rotate(-135deg); margin-top: 4px; }
.faq-item .faq-body { padding: 0 24px 22px; color: var(--sub-text); font-size: 15px; }
.faq-item[open] summary { color: var(--primary); }

/* ============ 联系 ============ */
.contact-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
}
.contact-card {
    background: var(--card-bg); border: 1px solid var(--border-light);
    border-radius: var(--radius); padding: 32px; text-align: center;
    box-shadow: var(--shadow);
}
.contact-card .feature-icon { margin: 0 auto 16px; }
.contact-card h3 { font-size: 17px; margin-bottom: 8px; }
.contact-card p { color: var(--sub-text); font-size: 15px; }
.contact-card a { color: var(--primary); font-weight: 600; }

/* ============ 页脚（备案信息） ============ */
.site-footer { background: var(--footer-bg); color: #D0D5DD; padding: 56px 0 32px; font-size: 14px; }
.footer-grid {
    display: grid; grid-template-columns: 1.4fr 1fr 1fr;
    gap: 40px; padding-bottom: 36px; border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}
.footer-brand { display: flex; align-items: center; gap: 10px; font-size: 19px; font-weight: 700; color: #fff; margin-bottom: 14px; }
.footer-brand svg { width: 28px; height: 28px; }
.footer-desc { line-height: 1.9; max-width: 30em; }
.footer-col h4 { color: #fff; font-size: 15px; margin-bottom: 16px; }
.footer-col ul { list-style: none; display: grid; gap: 10px; }
.footer-col a:hover { color: #fff; }

.footer-bottom { padding-top: 26px; text-align: center; line-height: 2.1; font-size: 13.5px; }
.footer-bottom a { color: #D0D5DD; }
.footer-bottom a:hover { color: #fff; }
.footer-bottom .beian-links { display: flex; flex-wrap: wrap; gap: 8px 18px; justify-content: center; align-items: center; }
.footer-bottom .icp-placeholder { color: var(--warning); font-weight: 600; }

/* ============ 政策页（隐私政策/用户协议） ============ */
.policy-page { padding: 64px 0 80px; background: var(--page-bg); }
.policy-article {
    max-width: 820px; margin: 0 auto; background: var(--card-bg);
    border: 1px solid var(--border-light); border-radius: var(--radius);
    padding: 52px 56px;
}
.policy-article h1 { font-size: 30px; font-weight: 800; margin-bottom: 8px; }
.policy-article .policy-date { color: var(--tertiary-text); font-size: 14px; margin-bottom: 32px; }
.policy-article h2 { font-size: 20px; font-weight: 700; margin: 34px 0 12px; }
.policy-article h3 { font-size: 16.5px; font-weight: 700; margin: 22px 0 8px; }
.policy-article p, .policy-article li { color: var(--sub-text); font-size: 15.5px; margin-bottom: 10px; }
.policy-article ul, .policy-article ol { padding-left: 22px; }
.policy-article strong { color: var(--text); }
.policy-article table { width: 100%; border-collapse: collapse; margin: 16px 0; font-size: 14.5px; }
.policy-article th, .policy-article td { border: 1px solid var(--border-light); padding: 10px 14px; text-align: left; color: var(--sub-text); }
.policy-article th { background: var(--page-bg); color: var(--text); }
.back-link { display: inline-block; margin-bottom: 24px; color: var(--primary); font-weight: 600; }

/* ============ 响应式 ============ */
@media (max-width: 900px) {
    .hero-grid { grid-template-columns: 1fr; gap: 40px; }
    .hero-visual { order: -1; }
    .download-card { grid-template-columns: 1fr; padding: 40px 32px; }
    .footer-grid { grid-template-columns: 1fr; gap: 32px; }
    .policy-article { padding: 36px 26px; }
}

@media (max-width: 768px) {
    .nav-burger {
        display: flex; flex-direction: column; gap: 5px;
        padding: 10px; cursor: pointer;
    }
    .nav-burger span { width: 22px; height: 2px; background: var(--text); border-radius: 2px; transition: all 0.25s; }
    .nav-toggle:checked ~ .nav-burger span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
    .nav-toggle:checked ~ .nav-burger span:nth-child(2) { opacity: 0; }
    .nav-toggle:checked ~ .nav-burger span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

    .nav-menu {
        display: none; position: absolute; top: 64px; left: 0; right: 0;
        flex-direction: column; align-items: stretch; gap: 0;
        background: #fff; border-bottom: 1px solid var(--border-light);
        padding: 8px 24px 20px; box-shadow: var(--shadow);
    }
    .nav-toggle:checked ~ .nav-menu { display: flex; }
    .nav-menu li { border-bottom: 1px solid var(--border-light); }
    .nav-menu li:last-child { border-bottom: none; padding-top: 12px; }
    .nav-menu a { display: block; padding: 14px 0; }
    .nav-menu .btn-nav { text-align: center; }

    .hero { padding: 56px 0 48px; }
    .hero-sub { font-size: 16px; }
    .section { padding: 56px 0; }
    .hero-actions .btn { flex: 1 1 100%; }
}