/* 第1套 · 根域名版 · 经典蓝白官方风 */
* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --brand: #2563eb;
  --brand-dark: #1e40af;
  --ink: #1f2937;
  --sub: #5b6472;
  --line: #e5e9f0;
  --bg: #f6f8fc;
  --card: #ffffff;
}
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.85;
  font-size: 16px;
}
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-dark); }
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 24px; }

/* 页头 */
.site-header {
  background: #fff;
  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;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 20px; color: var(--ink); }
.brand svg { display: block; }
.site-nav { display: flex; gap: 8px; }
.site-nav a {
  padding: 8px 18px; border-radius: 999px; color: var(--sub);
  font-size: 15px; transition: background .2s, color .2s;
}
.site-nav a:hover { background: #eef4ff; color: var(--brand); }
.site-nav a.active { background: var(--brand); color: #fff; }

/* Hero */
.hero {
  background: linear-gradient(135deg, #1e40af 0%, #2563eb 55%, #3b82f6 100%);
  color: #fff; padding: 84px 0 96px;
}
.hero .wrap { display: flex; align-items: center; gap: 48px; flex-wrap: wrap; }
.hero-text { flex: 1 1 460px; }
.hero-text h1 { font-size: 40px; line-height: 1.35; margin-bottom: 20px; letter-spacing: 1px; }
.hero-text p { font-size: 17px; opacity: .92; margin-bottom: 32px; max-width: 560px; }
.hero-art { flex: 0 1 360px; display: flex; justify-content: center; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 34px; border-radius: 10px; font-size: 17px; font-weight: 600;
  transition: transform .15s, box-shadow .15s, background .2s;
  cursor: pointer; border: none;
}
.btn-primary { background: #fff; color: var(--brand-dark); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(0,0,0,.22); color: var(--brand-dark); }
.btn-brand { background: var(--brand); color: #fff; }
.btn-brand:hover { background: var(--brand-dark); transform: translateY(-2px); box-shadow: 0 10px 22px rgba(37,99,235,.35); color:#fff; }
.btn-ghost { background: transparent; color: #fff; border: 1px solid rgba(255,255,255,.6); }
.btn-ghost:hover { background: rgba(255,255,255,.12); color: #fff; }
.hero-note { margin-top: 16px; font-size: 13px; opacity: .75; }

/* 通用区块 */
.section { padding: 72px 0; }
.section:nth-of-type(even) { background: #fff; }
.sec-head { text-align: center; max-width: 720px; margin: 0 auto 44px; }
.sec-head h2 { font-size: 30px; margin-bottom: 14px; color: var(--ink); }
.sec-head p { color: var(--sub); font-size: 16px; }

.grid { display: grid; gap: 22px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px;
  padding: 28px 26px; transition: box-shadow .2s, transform .2s;
}
.card:hover { box-shadow: 0 12px 30px rgba(30,64,175,.10); transform: translateY(-3px); }
.card h3 { font-size: 18px; margin: 14px 0 10px; color: var(--ink); }
.card p { color: var(--sub); font-size: 15px; }
.icon-chip {
  width: 46px; height: 46px; border-radius: 12px;
  background: #eaf1ff; display: flex; align-items: center; justify-content: center;
}

/* 平台下载条 */
.platform-bar {
  display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px;
}
.platform-item {
  background: #fff; border: 1px solid var(--line); border-radius: 12px;
  text-align: center; padding: 24px 12px;
}
.platform-item strong { display: block; margin: 10px 0 4px; font-size: 16px; }
.platform-item span { font-size: 13px; color: var(--sub); display: block; margin-bottom: 12px; }

/* 数据背书 */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; text-align: center; }
.stat-num { font-size: 34px; font-weight: 800; color: var(--brand); }
.stat-label { color: var(--sub); font-size: 14px; margin-top: 6px; }

/* 对比表 */
.compare { width: 100%; border-collapse: collapse; background: #fff; border-radius: 14px; overflow: hidden; }
.compare th, .compare td { padding: 14px 18px; border-bottom: 1px solid var(--line); text-align: left; font-size: 15px; }
.compare th { background: #eaf1ff; color: var(--brand-dark); }
.compare tr:last-child td { border-bottom: none; }

/* 评价 */
.quote-card { position: relative; }
.quote-card .who { display: flex; align-items: center; gap: 12px; margin-top: 16px; }
.avatar {
  width: 42px; height: 42px; border-radius: 50%; background: var(--brand);
  color: #fff; display: flex; align-items: center; justify-content: center; font-weight: 700;
}
.who-name { font-weight: 600; font-size: 15px; }
.who-role { font-size: 13px; color: var(--sub); }

/* FAQ */
.faq-item { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 22px 26px; margin-bottom: 14px; }
.faq-item h3 { font-size: 17px; color: var(--ink); margin-bottom: 8px; }
.faq-item p { color: var(--sub); font-size: 15px; }

/* 步骤 */
.steps { counter-reset: step; }
.step { display: flex; gap: 18px; background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 22px 24px; margin-bottom: 16px; }
.step::before {
  counter-increment: step; content: counter(step);
  flex: 0 0 40px; height: 40px; border-radius: 50%;
  background: var(--brand); color: #fff; font-weight: 700; font-size: 17px;
  display: flex; align-items: center; justify-content: center;
}
.step h3 { font-size: 17px; margin-bottom: 6px; }
.step p { color: var(--sub); font-size: 15px; }

/* 文章页 */
.article-body h2 { font-size: 24px; margin: 40px 0 16px; padding-left: 14px; border-left: 4px solid var(--brand); }
.article-body h3 { font-size: 18px; margin: 26px 0 10px; }
.article-body p { margin-bottom: 16px; color: #374151; }
.article-body ul { margin: 0 0 16px 22px; color: #374151; }
.article-body li { margin-bottom: 8px; }
.cta-band {
  background: linear-gradient(135deg, #1e40af, #3b82f6);
  border-radius: 16px; color: #fff; text-align: center; padding: 44px 28px; margin-top: 48px;
}
.cta-band h2 { color: #fff; border: none; padding: 0; margin: 0 0 12px; font-size: 26px; }
.cta-band p { opacity: .9; margin-bottom: 24px; }

/* 页脚 */
.site-footer { background: #101828; color: #98a2b3; padding: 44px 0 28px; font-size: 14px; }
.site-footer .foot-grid { display: flex; justify-content: space-between; gap: 32px; flex-wrap: wrap; margin-bottom: 26px; }
.site-footer h4 { color: #e4e7ec; font-size: 15px; margin-bottom: 12px; }
.site-footer a { color: #98a2b3; display: block; margin-bottom: 8px; }
.site-footer a:hover { color: #fff; }
.foot-legal { border-top: 1px solid #263042; padding-top: 20px; line-height: 1.9; }
.foot-safe { color: #7ee2b0; margin-bottom: 6px; }

@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .platform-bar { grid-template-columns: repeat(3, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .hero-text h1 { font-size: 30px; }
}
@media (max-width: 600px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .platform-bar { grid-template-columns: repeat(2, 1fr); }
  .site-nav a { padding: 6px 10px; font-size: 14px; }
}