/* 博文元启（AI智服）官网样式 · 纯静态，无构建依赖
   设计口径：稳、清楚、可审核（法务信息优先可见） */

:root {
  --brand: #1d4ed8;
  --brand-2: #3b82f6;
  --brand-soft: #eef4ff;
  --ink: #0f172a;
  --ink-2: #334155;
  --muted: #5b667a;
  --line: #e4e9f2;
  --bg: #ffffff;
  --bg-soft: #f6f9ff;
  --ok: #0f9d58;
  --warn-bg: #fff8ed;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(15, 23, 42, .08);
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", "WenQuanYi Micro Hei",
    "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font: 16px/1.75 var(--sans);
  color: var(--ink-2);
  background: var(--bg);
  letter-spacing: .01em;
}

a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 { color: var(--ink); line-height: 1.35; margin: 0 0 .5em; font-weight: 700; }
h1 { font-size: 2.35rem; letter-spacing: -.01em; }
h2 { font-size: 1.65rem; }
h3 { font-size: 1.12rem; }
p { margin: 0 0 1em; }
ul, ol { margin: 0 0 1em; padding-left: 1.25em; }
li { margin: .35em 0; }
small { color: var(--muted); }

.wrap { width: 100%; max-width: 1120px; margin: 0 auto; padding: 0 20px; }
.section { padding: 64px 0; }
.section.soft { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-head { max-width: 780px; margin-bottom: 34px; }
.section-head p { color: var(--muted); margin-bottom: 0; }

/* 顶部导航 */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--line);
}
.site-nav { display: flex; align-items: center; gap: 18px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--ink); font-size: 1.02rem; white-space: nowrap; }
.brand:hover { text-decoration: none; }
.brand img { width: 30px; height: 30px; display: block; }
.brand .brand-sub { font-weight: 400; font-size: .82rem; color: var(--muted); margin-left: 2px; }
.nav-links { display: flex; align-items: center; gap: 18px; margin-left: auto; font-size: .94rem; }
.nav-links a { color: var(--ink-2); }
.nav-links a:hover { color: var(--brand); text-decoration: none; }
.nav-actions { display: flex; align-items: center; gap: 10px; margin-left: 8px; }

/* 按钮 */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 10px 18px; border-radius: 10px; border: 1px solid var(--line);
  font-size: .95rem; font-weight: 600; color: var(--ink); background: #fff;
  cursor: pointer; transition: .18s ease; white-space: nowrap;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-primary { background: linear-gradient(135deg, var(--brand), var(--brand-2)); border-color: transparent; color: #fff; }
.btn-primary:hover { color: #fff; }
.btn-ghost { background: transparent; }
.btn-lg { padding: 13px 24px; font-size: 1rem; }

/* 首屏 */
.hero { padding: 72px 0 60px; background:
  radial-gradient(1000px 380px at 15% -10%, #e8f0ff 0%, rgba(255,255,255,0) 60%),
  radial-gradient(800px 320px at 95% 0%, #eafaf3 0%, rgba(255,255,255,0) 55%), #fff; }
.hero-grid { display: grid; grid-template-columns: 1.15fr .85fr; gap: 42px; align-items: center; }
.hero .eyebrow { display: inline-block; font-size: .82rem; font-weight: 600; color: var(--brand);
  background: var(--brand-soft); border: 1px solid #d7e3ff; border-radius: 999px; padding: 4px 12px; margin-bottom: 16px; }
.hero p.lead { font-size: 1.08rem; color: var(--ink-2); margin-bottom: 24px; }
.hero-cta { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 18px; }
.hero-note { font-size: .86rem; color: var(--muted); }
.hero-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 22px; }
.hero-card h3 { font-size: 1rem; margin-bottom: 14px; }
.metric { display: flex; justify-content: space-between; gap: 12px; padding: 10px 0; border-bottom: 1px dashed var(--line); font-size: .92rem; }
.metric:last-child { border-bottom: 0; }
.metric b { color: var(--ink); }

/* 卡片网格 */
.grid { display: grid; gap: 18px; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }
.card h3 { margin-bottom: 8px; }
.card p:last-child { margin-bottom: 0; }
.card .icon { width: 38px; height: 38px; border-radius: 10px; background: var(--brand-soft); color: var(--brand);
  display: flex; align-items: center; justify-content: center; font-weight: 700; margin-bottom: 12px; }

/* 步骤 */
.steps { counter-reset: step; display: grid; gap: 16px; grid-template-columns: repeat(4, minmax(0, 1fr)); }
.step { position: relative; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px 18px 18px; }
.step::before { counter-increment: step; content: counter(step); position: absolute; top: -12px; left: 18px;
  width: 26px; height: 26px; border-radius: 50%; background: var(--brand); color: #fff;
  font-size: .82rem; font-weight: 700; display: flex; align-items: center; justify-content: center; }
.step h4 { margin: 8px 0 6px; font-size: .98rem; }
.step p { margin: 0; font-size: .9rem; color: var(--muted); }

/* 价格表 */
.pricing { display: grid; gap: 18px; grid-template-columns: repeat(4, minmax(0, 1fr)); align-items: stretch; }
.plan { display: flex; flex-direction: column; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }
.plan.featured { border-color: var(--brand); box-shadow: 0 12px 34px rgba(29, 78, 216, .14); position: relative; }
.plan.featured::after { content: "推荐"; position: absolute; top: -11px; right: 16px; background: var(--brand); color: #fff;
  font-size: .74rem; padding: 2px 10px; border-radius: 999px; }
.plan h3 { font-size: 1.05rem; margin-bottom: 6px; }
.plan .price { font-size: 1.9rem; font-weight: 700; color: var(--ink); line-height: 1.2; }
.plan .price span { font-size: .85rem; font-weight: 400; color: var(--muted); }
.plan .plan-desc { font-size: .88rem; color: var(--muted); min-height: 44px; margin: 6px 0 14px; }
.plan ul { list-style: none; padding: 0; margin: 0 0 18px; font-size: .9rem; flex: 1; }
.plan ul li { padding-left: 20px; position: relative; margin: .4em 0; }
.plan ul li::before { content: "✓"; position: absolute; left: 0; color: var(--ok); font-weight: 700; }
.plan .btn { width: 100%; }

/* 表格 */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
table { width: 100%; border-collapse: collapse; font-size: .92rem; min-width: 620px; }
th, td { padding: 12px 14px; text-align: left; border-bottom: 1px solid var(--line); vertical-align: top; }
th { background: var(--bg-soft); color: var(--ink); font-weight: 600; white-space: nowrap; }
tbody tr:last-child td { border-bottom: 0; }

/* 提示条 */
.notice { border: 1px solid #ffe2b8; background: var(--warn-bg); color: #7c4a03; border-radius: 12px; padding: 14px 16px; font-size: .9rem; }
.notice strong { color: #7c4a03; }
.notice p:last-child { margin-bottom: 0; }
.tip { border-left: 3px solid var(--brand); background: var(--brand-soft); border-radius: 8px; padding: 12px 16px; font-size: .9rem; }
.tip p:last-child { margin-bottom: 0; }

/* 法务页排版 */
.legal { max-width: 860px; }
.legal h2 { margin-top: 2em; font-size: 1.22rem; }
.legal h3 { margin-top: 1.4em; font-size: 1.02rem; }
.legal ol { padding-left: 1.4em; }
.legal .legal-meta { color: var(--muted); font-size: .88rem; border-bottom: 1px solid var(--line); padding-bottom: 14px; margin-bottom: 22px; }

/* 页脚 */
.site-footer { background: #0b1220; color: #c7d2e4; padding: 46px 0 28px; font-size: .9rem; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 28px; }
.site-footer h4 { color: #fff; font-size: .95rem; margin-bottom: 12px; }
.site-footer a { color: #c7d2e4; }
.site-footer a:hover { color: #fff; }
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer li { margin: .45em 0; }
.footer-brand { display: flex; align-items: center; gap: 10px; color: #fff; font-weight: 700; margin-bottom: 10px; }
.footer-brand img { width: 28px; height: 28px; }
.footer-bottom { margin-top: 30px; padding-top: 18px; border-top: 1px solid #1e293b; color: #8b9bb4; font-size: .84rem; line-height: 2; }
.footer-bottom a { color: #8b9bb4; }

/* 响应式 */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; }
  .grid-3, .steps, .pricing { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  h1 { font-size: 1.72rem; }
  h2 { font-size: 1.35rem; }
  .section { padding: 44px 0; }
  .hero { padding: 44px 0 36px; }
  .grid-2, .grid-3, .steps, .pricing { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .site-nav { height: 58px; }
  .brand .brand-sub { display: none; }
}