/* ===== 基础 ===== */
* { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --primary: #2563eb;
  --primary-dark: #1e40af;
  --accent: #06b6d4;
  --ink: #0f172a;
  --muted: #64748b;
  --bg: #f8fafc;
  --card: #ffffff;
  --line: #e8edf3;
  --radius: 16px;
  --shadow-sm: 0 1px 3px rgba(15,23,42,.06), 0 1px 2px rgba(15,23,42,.04);
  --shadow-md: 0 10px 30px rgba(37,99,235,.10);
  --grad: linear-gradient(135deg, #1e3a8a 0%, #2563eb 55%, #06b6d4 100%);
}
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  color: var(--ink); line-height: 1.75; background: var(--bg);
  -webkit-font-smoothing: antialiased;
}
.wrap { max-width: 1140px; margin: 0 auto; padding: 0 22px; }
a { color: var(--primary); text-decoration: none; transition: .2s; }
img { max-width: 100%; }

/* ===== 头部 ===== */
.site-header {
  background: rgba(255,255,255,.85); backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line); position: sticky; top: 0; z-index: 50;
}
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { font-size: 21px; font-weight: 800; letter-spacing: -.5px;
  background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.site-header nav a { margin-left: 22px; color: var(--ink); font-size: 15px; font-weight: 500; }
.site-header nav a:hover { color: var(--primary); }
.cta-nav { background: var(--grad); color: #fff !important; padding: 8px 18px; border-radius: 999px; box-shadow: var(--shadow-sm); }
.cta-nav:hover { transform: translateY(-1px); box-shadow: var(--shadow-md); }

/* ===== 通用区块 ===== */
section { padding: 76px 0; }
.eyebrow { display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 1.5px;
  text-transform: uppercase; color: var(--primary); background: #eff4ff; padding: 5px 12px; border-radius: 999px; margin-bottom: 14px; }
h1 { font-size: 46px; line-height: 1.2; letter-spacing: -.5px; }
h2 { font-size: 32px; line-height: 1.3; letter-spacing: -.3px; margin-bottom: 14px; }
h3 { font-size: 20px; margin-bottom: 8px; }
.sub { font-size: 18px; color: var(--muted); max-width: 680px; }
.center { text-align: center; }
.center .sub { margin-left: auto; margin-right: auto; }

/* ===== Hero ===== */
.hero {
  position: relative; overflow: hidden; color: #fff;
  background: var(--grad);
  padding: 100px 0 92px;
}
.hero::before, .hero::after {
  content: ""; position: absolute; border-radius: 50%; filter: blur(40px); opacity: .35;
}
.hero::before { width: 380px; height: 380px; background: #22d3ee; top: -120px; right: -80px; }
.hero::after { width: 320px; height: 320px; background: #818cf8; bottom: -140px; left: -60px; }
.hero .wrap { position: relative; z-index: 1; }
.hero h1 { color: #fff; }
.hero .sub { color: rgba(255,255,255,.88); margin: 18px auto 32px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; justify-content: center; }
.btn {
  display: inline-block; background: #fff; color: var(--primary-dark); font-weight: 700;
  padding: 14px 30px; border-radius: 999px; font-size: 16px; box-shadow: var(--shadow-md);
}
.btn:hover { transform: translateY(-2px); }
.btn.ghost { background: rgba(255,255,255,.12); color: #fff; border: 1px solid rgba(255,255,255,.4); box-shadow: none; }
.trustbar { margin-top: 38px; display: flex; gap: 30px; justify-content: center; flex-wrap: wrap; color: rgba(255,255,255,.85); font-size: 14px; }
.trustbar span { display: inline-flex; align-items: center; gap: 7px; }

/* ===== 卡片网格 ===== */
.grid { display: grid; gap: 22px; }
.grid.c3 { grid-template-columns: repeat(3, 1fr); }
.grid.c2 { grid-template-columns: repeat(2, 1fr); }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow-sm); transition: .25s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: #cfe0ff; }
.card .ico { width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center;
  font-size: 22px; background: linear-gradient(135deg,#eff4ff,#e0f2fe); margin-bottom: 14px; }
.card h3 { color: var(--ink); }
.card p { color: var(--muted); margin-bottom: 12px; }
.card a.more { font-weight: 600; }

/* ===== 特性列表 ===== */
.feature-list { list-style: none; display: grid; gap: 14px; max-width: 760px; margin: 0 auto; }
.feature-list li { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 16px 20px;
  display: flex; gap: 12px; align-items: flex-start; box-shadow: var(--shadow-sm); }
.feature-list .ck { color: #16a34a; font-weight: 800; flex: none; }
.feature-list strong { color: var(--primary); }

/* ===== 数据条 ===== */
.stats { display: grid; grid-template-columns: repeat(4,1fr); gap: 18px; margin-top: 8px; }
.stat { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; text-align: center; box-shadow: var(--shadow-sm); }
.stat b { display: block; font-size: 34px; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.stat span { color: var(--muted); font-size: 14px; }

/* ===== 流程步骤 ===== */
.steps { display: grid; grid-template-columns: repeat(4,1fr); gap: 18px; counter-reset: step; }
.step { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px 22px; position: relative; box-shadow: var(--shadow-sm); }
.step::before { counter-increment: step; content: counter(step); position: absolute; top: -16px; left: 22px;
  width: 34px; height: 34px; border-radius: 50%; background: var(--grad); color: #fff; font-weight: 800; display: grid; place-items: center; }
.step h3 { margin-top: 8px; }

/* ===== 示例场景（案例）===== */
.case { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); transition:.25s; }
.case:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.case .top { padding: 22px 24px; background: linear-gradient(135deg,#f0f6ff,#e6fbff); }
.case .top .tag { font-size: 12px; font-weight: 700; color: var(--primary); }
.case .body { padding: 22px 24px; }
.case .body p { color: var(--muted); margin-bottom: 10px; }
.case .body .res { color: var(--ink); font-weight: 600; }
.placeholder-note { font-size: 13px; color: #b45309; background: #fffbeb; border: 1px dashed #fcd34d; padding: 10px 14px; border-radius: 10px; margin-top: 18px; }

/* ===== FAQ ===== */
.faq details { max-width: 800px; margin: 0 auto 12px; background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 4px 20px; box-shadow: var(--shadow-sm); }
.faq summary { cursor: pointer; font-weight: 600; font-size: 16px; padding: 14px 0; list-style: none; display: flex; justify-content: space-between; align-items: center; }
.faq summary::after { content: "+"; font-size: 22px; color: var(--primary); font-weight: 400; }
.faq details[open] summary::after { content: "−"; }
.faq p { color: var(--muted); padding-bottom: 14px; }

/* ===== 文章 ===== */
.article .wrap { max-width: 780px; }
.article p { margin: 14px 0; color: #334155; }
.article h2 { margin-top: 34px; }
.article ul { margin: 12px 0 12px 20px; color: #334155; }
.article li { margin: 6px 0; }

/* ===== CTA / 联系 ===== */
.contact { background: var(--grad); color: #fff; text-align: center; border-radius: 0; }
.contact h2, .contact .sub { color: #fff; }
.contact .sub { color: rgba(255,255,255,.88); margin: 0 auto 22px; }
.contact .note { font-size: 13px; color: #fde68a; margin-top: 16px; }
.contact .wecom-box { display:inline-block; background:rgba(255,255,255,.12); border:1px solid rgba(255,255,255,.35); border-radius:16px; padding:18px 18px 14px; margin-top:22px; backdrop-filter: blur(4px); }
.contact .qr-img { width:180px; height:180px; border-radius:10px; background:#fff; padding:8px; box-shadow:0 6px 20px rgba(0,0,0,.18); }
.contact .wx-title { color:#fff; font-weight:700; font-size:16px; margin:12px 0 4px; }
.contact .wx-sub { color:rgba(255,255,255,.85); font-size:13px; margin:0; }

/* ===== 页脚 ===== */
.site-footer { background: #0b1220; color: #94a3b8; padding: 30px 0; font-size: 13px; text-align: center; }

/* ===== 交替背景 ===== */
.section-alt { background: #fff; }

/* ===== 响应式 ===== */
@media (max-width: 880px) {
  .grid.c3, .grid.c2, .steps, .stats { grid-template-columns: 1fr 1fr; }
  h1 { font-size: 34px; } h2 { font-size: 26px; }
  .site-header nav a { margin-left: 12px; font-size: 13px; }
}
@media (max-width: 560px) {
  .grid.c3, .grid.c2, .steps, .stats { grid-template-columns: 1fr; }
  .hero { padding: 72px 0; }
  .site-header nav a:not(.cta-nav) { display: none; }
}