:root {
    --bg: #0a0e1a;
    --bg-alt: #0f1525;
    --surface: #141b2e;
    --surface-2: #1b2438;
    --border: #243049;
    --text: #e8edf7;
    --text-muted: #9aa6bd;
    --primary: #0ea5e9;
    --primary-2: #6366f1;
    --accent: #22d3ee;
    --grad: linear-gradient(135deg, #0ea5e9 0%, #6366f1 100%);
    --radius: 16px;
    --maxw: 1200px;
    --shadow: 0 10px 40px rgba(0, 0, 0, .35);
}

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

html { scroll-behavior: smooth; }

body {
    font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

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

.container {
    width: 100%;
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 24px;
}

/* ---------- 按钮 ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 13px 28px;
    border-radius: 999px;
    font-weight: 600;
    font-size: 15px;
    cursor: pointer;
    border: 1px solid transparent;
    transition: transform .2s, box-shadow .2s, background .2s;
    white-space: nowrap;
}
.btn-primary {
    background: var(--grad);
    color: #fff;
    box-shadow: 0 8px 24px rgba(14, 165, 233, .35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 32px rgba(14, 165, 233, .5); }
.btn-ghost {
    background: transparent;
    color: var(--text);
    border-color: var(--border);
}
.btn-ghost:hover { border-color: var(--primary); color: var(--primary); }

/* ---------- Header ---------- */
.site-header {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
    background: rgba(10, 14, 26, .55);
    border-bottom: 1px solid transparent;
    transition: background .3s, border-color .3s;
}
.site-header.scrolled {
    background: rgba(10, 14, 26, .92);
    border-bottom-color: var(--border);
}
.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}
.logo { display: flex; align-items: center; gap: 12px; }
.logo-mark {
    width: 40px; height: 40px;
    display: grid; place-items: center;
    border-radius: 12px;
    background: var(--grad);
    font-weight: 800;
    font-size: 20px;
    color: #fff;
}
.logo-text { font-weight: 700; font-size: 18px; display: flex; flex-direction: column; line-height: 1.1; }
.logo-text small { font-size: 11px; color: var(--text-muted); font-weight: 500; letter-spacing: 1px; }

.main-nav > ul { display: flex; gap: 28px; list-style: none; }
.main-nav a { font-size: 15px; color: var(--text-muted); transition: color .2s; position: relative; padding: 6px 0; }
.main-nav a:hover, .main-nav a.active,
.has-dropdown:hover > a, .has-dropdown.open > a { color: var(--text); }
.main-nav a.active::after,
.has-dropdown:hover > a::after, .has-dropdown.open > a::after {
    content: ""; position: absolute; left: 0; bottom: -2px; width: 100%; height: 2px; background: var(--grad); border-radius: 2px;
}
.has-dropdown { position: relative; }
.dropdown {
    position: absolute; top: 100%; left: -18px; transform: translateY(8px);
    display: flex; flex-direction: column; gap: 0;
    background: var(--surface); border: 1px solid var(--border); border-radius: 12px;
    padding: 4px; min-width: 200px; list-style: none; opacity: 0; visibility: hidden;
    transition: opacity .2s, transform .2s; box-shadow: var(--shadow); z-index: 20;
}
.has-dropdown:hover .dropdown,
.has-dropdown.open .dropdown { opacity: 1; visibility: visible; transform: translateY(4px); }
.dropdown li { width: 100%; list-style: none; }
.dropdown a { display: block; padding: 6px 12px; border-radius: 8px; font-size: 14px; white-space: nowrap; }
.dropdown a:hover { background: var(--surface-2); color: var(--text); }

.header-cta { padding: 10px 22px; font-size: 14px; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--text); border-radius: 2px; transition: .3s; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero { position: relative; padding: 160px 0 100px; overflow: hidden; }
.hero-bg {
    position: absolute; inset: 0;
    background:
        radial-gradient(600px 400px at 20% 20%, rgba(14, 165, 233, .25), transparent 60%),
        radial-gradient(500px 500px at 85% 30%, rgba(99, 102, 241, .22), transparent 60%),
        radial-gradient(700px 500px at 50% 100%, rgba(34, 211, 238, .12), transparent 60%);
    z-index: -1;
}
.hero-bg::after {
    content: ""; position: absolute; inset: 0;
    background-image: linear-gradient(rgba(255,255,255,.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.03) 1px, transparent 1px);
    background-size: 44px 44px;
    mask-image: radial-gradient(circle at 50% 40%, #000, transparent 75%);
}
.hero-inner { text-align: center; max-width: var(--maxw); margin: 0 auto; }
.hero-eyebrow {
    display: inline-block; padding: 6px 16px; border: 1px solid var(--border);
    border-radius: 999px; font-size: 13px; color: var(--accent); margin-bottom: 24px;
    background: rgba(34, 211, 238, .08);
}
.hero-title {
    font-size: clamp(36px, 6vw, 64px); line-height: 1.15; font-weight: 800; letter-spacing: -1px;
    background: linear-gradient(180deg, #fff, #b8c4dc);
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero-sub { font-size: 18px; color: var(--text-muted); margin: 24px auto 36px; max-width: 860px; }
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-stats {
    display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
    margin-top: 72px; padding-top: 48px; border-top: 1px solid var(--border);
}
.stat strong { display: block; font-size: 34px; font-weight: 800; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.stat span { font-size: 13px; color: var(--text-muted); }

/* ---------- Section ---------- */
.section { padding: 100px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 56px; }
.section-tag { font-size: 13px; letter-spacing: 3px; color: var(--primary); font-weight: 600; }
.section-head h2 { font-size: clamp(28px, 4vw, 42px); margin: 12px 0 14px; font-weight: 800; }
.section-head p { color: var(--text-muted); font-size: 16px; }

/* ---------- 业务卡片 ---------- */
.biz-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.biz-card {
    background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
    padding: 32px 26px; transition: transform .25s, border-color .25s, box-shadow .25s;
    display: flex; flex-direction: column;
}
.biz-card:hover { transform: translateY(-6px); border-color: var(--primary); box-shadow: var(--shadow); }
.biz-icon {
    width: 56px; height: 56px; border-radius: 14px; display: grid; place-items: center;
    font-size: 28px; background: var(--surface-2); margin-bottom: 20px;
}
.biz-card h3 { font-size: 19px; margin-bottom: 12px; }
.biz-card p { color: var(--text-muted); font-size: 14px; flex: 1; }
.biz-link { margin-top: 18px; color: var(--primary); font-size: 14px; font-weight: 600; }

/* ---------- 优势 ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.feature {
    background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px;
}
.feature h4 { font-size: 17px; margin-bottom: 10px; color: var(--accent); }
.feature p { color: var(--text-muted); font-size: 14px; }

/* ---------- CTA band ---------- */
.cta-band { padding: 90px 0; background: var(--grad); text-align: center; }
.cta-inner h2 { font-size: clamp(26px, 4vw, 40px); color: #fff; margin-bottom: 14px; }
.cta-inner p { color: rgba(255,255,255,.85); margin-bottom: 28px; font-size: 17px; }
.cta-band .btn-primary { background: #fff; color: var(--primary-2); box-shadow: 0 10px 30px rgba(0,0,0,.25); }
.cta-band .btn-primary:hover { transform: translateY(-2px); }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--bg-alt); padding: 64px 0 0; border-top: 1px solid var(--border); }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 40px; padding-bottom: 48px; }
.footer-brand p { color: var(--text-muted); font-size: 14px; margin-top: 14px; }
.footer-col h4 { font-size: 15px; margin-bottom: 16px; }
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer-col a { color: var(--text-muted); font-size: 14px; transition: color .2s; }
.footer-col a:hover { color: var(--primary); }
.muted { color: var(--text-muted); }
.footer-bottom { border-top: 1px solid var(--border); padding: 24px 0; text-align: center; color: var(--text-muted); font-size: 13px; }

/* ---------- 平台详情 上下页导航 ---------- */
.plat-nav {
    max-width: var(--maxw); margin: 0 auto; padding: 40px 24px 8px;
    display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap;
}
.plat-nav a {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 10px 18px; border: 1px solid var(--border); border-radius: 999px;
    background: var(--surface); color: var(--text); font-size: 14px; text-decoration: none;
    transition: border-color .2s, color .2s, transform .2s;
}
.plat-nav a:hover { border-color: var(--primary); color: #fff; transform: translateY(-2px); }
.plat-nav .pn-home { color: var(--text-muted); }
.plat-nav .pn-prev { margin-right: auto; }
.plat-nav .pn-next { margin-left: auto; }

/* ---------- 首页 Hero 科技背景 ---------- */
.hero {
    position: relative; overflow: hidden;
    background:
        radial-gradient(60% 60% at 70% 20%, rgba(99,102,241,.18), transparent 70%),
        radial-gradient(50% 50% at 20% 80%, rgba(14,165,233,.18), transparent 70%),
        var(--bg);
}
.hero::before {
    content: ""; position: absolute; inset: 0; z-index: 0; pointer-events: none;
    background-image:
        linear-gradient(rgba(99,102,241,.08) 1px, transparent 1px),
        linear-gradient(90deg, rgba(99,102,241,.08) 1px, transparent 1px);
    background-size: 44px 44px;
    mask-image: radial-gradient(80% 60% at 50% 30%, #000 30%, transparent 80%);
    -webkit-mask-image: radial-gradient(80% 60% at 50% 30%, #000 30%, transparent 80%);
    animation: gridFloat 24s linear infinite;
}
.hero > * { position: relative; z-index: 1; }
@keyframes gridFloat { from { background-position: 0 0, 0 0; } to { background-position: 44px 44px, 44px 44px; } }
@media (prefers-reduced-motion: reduce) { .hero::before { animation: none; } }

/* ---------- 自研平台详情卡片 ---------- */
.plat-card {
    display: block; text-decoration: none; color: inherit;
    background: linear-gradient(160deg, var(--surface-2), var(--surface));
    border: 1px solid var(--border); border-radius: var(--radius);
    padding: 28px 30px; margin-bottom: 22px;
    box-shadow: var(--shadow);
    transition: border-color .25s, transform .2s, box-shadow .25s;
}
.plat-card:hover {
    border-color: var(--primary); transform: translateY(-4px);
    box-shadow: 0 16px 48px rgba(14, 165, 233, .15);
}
.plat-head { display: flex; align-items: center; gap: 16px; margin-bottom: 14px; }
.plat-no {
    flex: none; width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center;
    background: var(--grad); color: #fff; font-weight: 800; font-size: 16px;
}
.plat-head h3 { font-size: 21px; transition: color .2s; }
.plat-card:hover .plat-head h3 { color: var(--primary); }
.plat-desc { color: var(--text-muted); font-size: 14px; margin-bottom: 16px; }
.plat-link {
    display: inline-block; font-size: 13px; font-weight: 700; color: var(--primary);
    letter-spacing: .04em;
}

/* ---------- 平台矩阵 CTA ---------- */
.cta-block {
    text-align: center; padding: 72px 0;
    background: radial-gradient(60% 120% at 50% 0%, rgba(14,165,233,.12), transparent), var(--bg-alt);
}
.cta-block h2 { font-size: 28px; margin-bottom: 12px; }
.cta-block p { color: var(--text-muted); margin-bottom: 26px; }
.plat-desc { color: var(--text-muted); font-size: 15px; margin-bottom: 14px; }
.plat-profit {
    background: var(--surface-2); border: 1px solid var(--border); border-radius: 10px;
    padding: 14px 16px; font-size: 14px; color: var(--text); margin-bottom: 10px; line-height: 1.8;
}
.plat-profit strong { color: var(--accent); }
.plat-note { font-size: 13px; color: var(--text-muted); }
.plat-note strong { color: var(--primary); }

/* ---------- 内页通用 ---------- */
.page-hero { padding: 150px 0 60px; text-align: center; background: var(--bg-alt); border-bottom: 1px solid var(--border); position: relative; overflow: hidden; }
.page-hero::before {
    content: ""; position: absolute; inset: 0;
    background: radial-gradient(500px 300px at 50% 0%, rgba(14,165,233,.18), transparent 60%);
}
.page-hero .container { position: relative; }
.page-hero h1 { font-size: clamp(30px, 5vw, 48px); font-weight: 800; margin-bottom: 16px; }
.page-hero p { color: var(--text-muted); max-width: 640px; margin: 0 auto; font-size: 17px; }

.breadcrumb { font-size: 13px; color: var(--text-muted); margin-bottom: 18px; }
.breadcrumb a:hover { color: var(--primary); }

/* 内页内容块 */
.content-block { padding: 80px 0; }
.content-alt { background: var(--bg-alt); }
.feature-row { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; margin-bottom: 64px; }
.feature-row:last-child { margin-bottom: 0; }
.feature-row.reverse .feature-text { order: 2; }
.feature-text h3 { font-size: 24px; margin-bottom: 14px; }
.feature-text p { color: var(--text-muted); margin-bottom: 16px; }
.feature-list { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.feature-list li { position: relative; padding-left: 26px; color: var(--text); font-size: 15px; }
.feature-list li::before { content: "✓"; position: absolute; left: 0; color: var(--accent); font-weight: 700; }
.feature-visual {
    background: linear-gradient(160deg, var(--surface-2), var(--surface));
    border: 1px solid var(--border); border-radius: var(--radius); min-height: 280px;
    display: grid; place-items: center; padding: 32px;
}
.feature-visual .placeholder-icon { font-size: 64px; opacity: .5; }

/* 卡片列表 */
.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.info-card {
    background: linear-gradient(160deg, var(--surface-2), var(--surface));
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow);
    transition: transform .2s, border-color .2s, box-shadow .2s;
}
.info-card:hover {
    transform: translateY(-4px);
    border-color: var(--primary);
    box-shadow: 0 16px 48px rgba(14, 165, 233, .15);
}
.info-card .ic { font-size: 30px; margin-bottom: 14px; }
.info-card h4 { font-size: 17px; margin-bottom: 8px; }
.info-card p { color: var(--text-muted); font-size: 14px; line-height: 1.7; }

/* 时间线 / 流程 */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; counter-reset: step; }
.step { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px 22px; position: relative; }
.step::before { counter-increment: step; content: "0" counter(step); position: absolute; top: 18px; right: 22px; font-size: 28px; font-weight: 800; color: var(--border); }
.step h4 { font-size: 16px; margin-bottom: 8px; color: var(--accent); }
.step p { color: var(--text-muted); font-size: 14px; }

/* 联系表单 */
.contact-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.contact-form { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 32px; }
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 14px; margin-bottom: 8px; color: var(--text-muted); }
.form-group input, .form-group textarea {
    width: 100%; padding: 12px 14px; background: var(--bg); border: 1px solid var(--border);
    border-radius: 10px; color: var(--text); font-size: 15px; font-family: inherit; transition: border-color .2s;
}
.form-group input:focus, .form-group textarea:focus { outline: none; border-color: var(--primary); }
.form-group textarea { resize: vertical; min-height: 120px; }
.contact-info h3 { font-size: 22px; margin-bottom: 18px; }
.contact-info ul { list-style: none; display: flex; flex-direction: column; gap: 14px; }
.contact-info li { display: flex; gap: 12px; align-items: flex-start; color: var(--text-muted); font-size: 15px; }
.contact-info li strong { color: var(--text); }

/* 新闻列表 */
.news-item { display: grid; grid-template-columns: 120px 1fr; gap: 24px; padding: 24px 0; border-bottom: 1px solid var(--border); }
.news-date { color: var(--primary); font-weight: 700; font-size: 15px; }
.news-item h3 { font-size: 18px; margin-bottom: 6px; }
.news-item p { color: var(--text-muted); font-size: 14px; }
.news-tag { display: inline-block; font-size: 12px; padding: 2px 10px; border-radius: 999px; background: var(--surface-2); color: var(--accent); margin-bottom: 8px; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
    .biz-grid, .feature-grid, .card-grid, .steps { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .hero-stats { grid-template-columns: repeat(2, 1fr); }
    .feature-row, .contact-wrap { grid-template-columns: 1fr; }
    .main-nav { display: none; }
    .nav-toggle { display: flex; }
    .site-header.open .main-nav {
        display: block; position: absolute; top: 72px; left: 0; right: 0;
        background: var(--bg); border-bottom: 1px solid var(--border); padding: 20px 24px;
    }
    .site-header.open .main-nav ul { flex-direction: column; gap: 14px; }
    .site-header.open .dropdown { position: static; transform: none; opacity: 1; visibility: visible; box-shadow: none; border: 0; padding-left: 14px; }
    .header-cta { display: none; }
}
@media (max-width: 560px) {
    .biz-grid, .feature-grid, .card-grid, .steps, .footer-grid { grid-template-columns: 1fr; }
    .news-item { grid-template-columns: 1fr; gap: 6px; }
    .hero { padding: 120px 0 70px; }
    .section { padding: 70px 0; }
    .hero-stats { gap: 6px; margin-top: 48px; padding-top: 32px; }
    .hero-stats .stat-num { font-size: 22px; }
    .hero-stats .stat-label { font-size: 12px; }
}