/* ============================================
   智见GEO - 官网样式（静态站，AI 搜索友好）
   ============================================ */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #eff6ff;
  --accent: #7c3aed;
  --text: #1f2937;
  --text-muted: #6b7280;
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --border: #e5e7eb;
  --success: #059669;
  --radius: 14px;
  --max-width: 1120px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

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

a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); }

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

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 20px; color: var(--text); }
.logo:hover { color: var(--text); }
.logo-mark {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff; display: flex; align-items: center; justify-content: center;
  font-size: 15px; font-weight: 800;
}
.nav-links { display: flex; align-items: center; gap: 28px; list-style: none; }
.nav-links a { color: var(--text); font-size: 15px; font-weight: 500; }
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
.nav-cta {
  background: var(--primary); color: #fff !important;
  padding: 9px 20px; border-radius: 999px; font-weight: 600;
}
.nav-cta:hover { background: var(--primary-dark); color: #fff !important; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text); margin: 5px 0; border-radius: 2px; }

/* ---------- Hero ---------- */
.hero {
  padding: 88px 0 72px;
  background:
    radial-gradient(800px 400px at 15% 0%, rgba(37,99,235,.10), transparent 60%),
    radial-gradient(700px 380px at 90% 10%, rgba(124,58,237,.10), transparent 60%),
    var(--bg);
  text-align: center;
}
.hero .badge {
  display: inline-block; background: var(--primary-light); color: var(--primary);
  font-size: 14px; font-weight: 600; padding: 6px 16px; border-radius: 999px; margin-bottom: 22px;
}
.hero h1 {
  font-size: clamp(30px, 5vw, 48px); line-height: 1.25; font-weight: 800;
  letter-spacing: .5px; max-width: 860px; margin: 0 auto 20px;
}
.hero h1 .grad {
  background: linear-gradient(120deg, var(--primary), var(--accent));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero .sub {
  font-size: 18px; color: var(--text-muted); max-width: 760px; margin: 0 auto 36px;
}
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 13px 30px; border-radius: 999px;
  font-weight: 600; font-size: 16px; transition: all .2s;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); color: #fff; transform: translateY(-2px); }
.btn-ghost { border: 1.5px solid var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--primary); color: var(--primary); }
.hero-stats {
  display: flex; justify-content: center; gap: 56px; flex-wrap: wrap;
  margin-top: 56px; padding-top: 36px; border-top: 1px solid var(--border);
}
.hero-stats .stat b { font-size: 30px; font-weight: 800; color: var(--primary); display: block; }
.hero-stats .stat span { font-size: 14px; color: var(--text-muted); }

/* ---------- 通用 Section ---------- */
section.block { padding: 76px 0; }
section.block.soft { background: var(--bg-soft); }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 52px; }
.section-head h2 { font-size: clamp(26px, 3.5vw, 36px); font-weight: 800; margin-bottom: 14px; }
.section-head p { color: var(--text-muted); font-size: 17px; }

/* ---------- 卡片网格 ---------- */
.grid { display: grid; gap: 24px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 30px 26px; transition: all .25s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 14px 34px rgba(37,99,235,.10); border-color: #bfdbfe; }
.card .icon {
  width: 50px; height: 50px; border-radius: 12px; margin-bottom: 18px;
  background: var(--primary-light); color: var(--primary);
  display: flex; align-items: center; justify-content: center; font-size: 24px; font-weight: 700;
}
.card h3 { font-size: 19px; margin-bottom: 10px; font-weight: 700; }
.card p { color: var(--text-muted); font-size: 15px; }

/* ---------- 服务流程 ---------- */
.steps { counter-reset: step; }
.step {
  position: relative; background: #fff; border: 1px solid var(--border);
  border-radius: var(--radius); padding: 30px 26px;
}
.step::before {
  counter-increment: step; content: counter(step);
  width: 40px; height: 40px; border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff; font-weight: 800; font-size: 17px;
  display: flex; align-items: center; justify-content: center; margin-bottom: 16px;
}
.step h3 { font-size: 18px; margin-bottom: 8px; }
.step p { font-size: 14px; color: var(--text-muted); }

/* ---------- 用户评价 ---------- */
.quote { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; }
.quote p { font-size: 15px; color: var(--text); margin-bottom: 18px; }
.quote .who { display: flex; align-items: center; gap: 12px; }
.quote .who .avatar {
  width: 42px; height: 42px; border-radius: 50%;
  background: var(--primary-light); color: var(--primary);
  display: flex; align-items: center; justify-content: center; font-weight: 700;
}
.quote .who b { display: block; font-size: 15px; }
.quote .who span { font-size: 13px; color: var(--text-muted); }

/* ---------- 文章卡片 ---------- */
.article-card { display: flex; flex-direction: column; }
.article-card .meta { display: flex; gap: 10px; align-items: center; font-size: 13px; color: var(--text-muted); margin-bottom: 12px; }
.article-card .tag {
  background: var(--primary-light); color: var(--primary);
  padding: 2px 12px; border-radius: 999px; font-weight: 600;
}
.article-card h3 { font-size: 18px; line-height: 1.5; }
.article-card h3 a { color: var(--text); }
.article-card h3 a:hover { color: var(--primary); }
.article-card p { flex: 1; }
.article-card .more { font-weight: 600; font-size: 14px; margin-top: 12px; }

/* ---------- FAQ ---------- */
.faq-item {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  margin-bottom: 14px; overflow: hidden;
}
.faq-item summary {
  cursor: pointer; padding: 20px 24px; font-weight: 700; font-size: 16px;
  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: "+"; font-size: 22px; color: var(--primary); font-weight: 400; transition: transform .2s; }
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item .faq-a { padding: 0 24px 22px; color: var(--text-muted); font-size: 15px; }

/* ---------- CTA ---------- */
.cta-band {
  background: linear-gradient(120deg, var(--primary), var(--accent));
  border-radius: 20px; color: #fff; text-align: center; padding: 60px 32px;
}
.cta-band h2 { font-size: clamp(24px, 3vw, 34px); margin-bottom: 12px; }
.cta-band p { opacity: .92; margin-bottom: 28px; }
.cta-band .btn-white { background: #fff; color: var(--primary); font-weight: 700; }
.cta-band .btn-white:hover { transform: translateY(-2px); color: var(--primary-dark); }

/* ---------- 页脚 ---------- */
.site-footer { background: #0f172a; color: #cbd5e1; padding: 60px 0 30px; margin-top: 80px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 36px; margin-bottom: 40px; }
.site-footer h4 { color: #fff; font-size: 15px; margin-bottom: 16px; }
.site-footer ul { list-style: none; }
.site-footer li { margin-bottom: 10px; font-size: 14px; }
.site-footer a { color: #cbd5e1; }
.site-footer a:hover { color: #fff; }
.site-footer .brand-desc { font-size: 14px; opacity: .85; max-width: 320px; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.12); padding-top: 24px;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; font-size: 13px; opacity: .75;
}

/* ---------- 文章页 ---------- */
.article-page { max-width: 800px; margin: 0 auto; padding: 56px 24px 40px; }
.article-page .crumbs { font-size: 14px; color: var(--text-muted); margin-bottom: 24px; }
.article-page h1 { font-size: clamp(26px, 4vw, 38px); line-height: 1.35; margin-bottom: 16px; }
.article-page .article-meta { display: flex; gap: 16px; flex-wrap: wrap; font-size: 14px; color: var(--text-muted); margin-bottom: 40px; }
.article-page h2 { font-size: 24px; margin: 44px 0 16px; padding-left: 12px; border-left: 4px solid var(--primary); }
.article-page h3 { font-size: 19px; margin: 30px 0 12px; }
.article-page p { margin-bottom: 16px; color: #374151; }
.article-page ul, .article-page ol { margin: 0 0 18px 24px; color: #374151; }
.article-page li { margin-bottom: 8px; }
.article-page blockquote {
  background: var(--primary-light); border-left: 4px solid var(--primary);
  padding: 16px 20px; border-radius: 8px; margin: 20px 0; color: var(--primary-dark);
}
.article-page table { width: 100%; border-collapse: collapse; margin: 20px 0; font-size: 15px; }
.article-page th, .article-page td { border: 1px solid var(--border); padding: 10px 14px; text-align: left; }
.article-page th { background: var(--bg-soft); }
.article-footer-nav {
  margin-top: 50px; padding-top: 24px; border-top: 1px solid var(--border);
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; font-size: 15px;
}

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .nav-links {
    display: none; position: absolute; top: 64px; left: 0; right: 0;
    background: #fff; flex-direction: column; padding: 20px 24px;
    border-bottom: 1px solid var(--border); gap: 16px; align-items: flex-start;
  }
  .nav-links.open { display: flex; }
  .nav-toggle { display: block; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .hero { padding: 56px 0 48px; }
  .hero-stats { gap: 28px; }
  section.block { padding: 52px 0; }
  .footer-grid { grid-template-columns: 1fr; }
}