:root {
  color-scheme: light;
  --bg: #f5f7fb;
  --surface: rgba(255, 255, 255, 0.9);
  --surface-strong: #ffffff;
  --text: #132238;
  --text-secondary: #5b6b81;
  --primary: #2563eb;
  --primary-soft: rgba(37, 99, 235, 0.12);
  --border: rgba(148, 163, 184, 0.24);
  --shadow: 0 18px 45px rgba(15, 23, 42, 0.08);
  --radius: 24px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Inter", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(59, 130, 246, 0.14), transparent 30%),
    radial-gradient(circle at top right, rgba(99, 102, 241, 0.12), transparent 28%),
    var(--bg);
  line-height: 1.7;
}

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

 a:hover {
  text-decoration: underline;
}

.container {
  width: min(960px, calc(100% - 32px));
  margin: 0 auto;
}

.hero {
  padding: 56px 0 24px;
}

.hero-card {
  background: linear-gradient(135deg, rgba(15, 23, 42, 0.96), rgba(37, 99, 235, 0.92));
  color: #fff;
  border-radius: 32px;
  padding: 32px;
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.22);
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: rgba(255, 255, 255, 0.88);
  font-size: 0.95rem;
  margin-bottom: 18px;
}

.back-link:hover {
  color: #fff;
  text-decoration: none;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  font-size: 0.85rem;
  letter-spacing: 0.02em;
}

.hero h1 {
  margin: 18px 0 12px;
  font-size: clamp(2rem, 5vw, 3rem);
  line-height: 1.15;
}

.hero p {
  margin: 0;
  max-width: 720px;
  color: rgba(255, 255, 255, 0.82);
}

.meta-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

.meta-pill {
  display: inline-flex;
  align-items: center;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.9);
  font-size: 0.9rem;
}

.doc-layout {
  padding: 8px 0 56px;
}

.card {
  background: var(--surface);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.doc-nav {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
  margin-bottom: 18px;
  padding: 18px;
}

.doc-nav a {
  display: block;
  padding: 16px 18px;
  border-radius: 18px;
  background: var(--surface-strong);
  border: 1px solid var(--border);
  color: var(--text);
  transition: transform 0.18s ease, border-color 0.18s ease, box-shadow 0.18s ease;
}

.doc-nav a:hover {
  text-decoration: none;
  transform: translateY(-2px);
  border-color: rgba(37, 99, 235, 0.35);
  box-shadow: 0 14px 30px rgba(37, 99, 235, 0.08);
}

.doc-nav a.active {
  border-color: rgba(37, 99, 235, 0.45);
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.12), rgba(37, 99, 235, 0.04));
}

.doc-nav strong {
  display: block;
  margin-bottom: 6px;
}

.doc-nav span {
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.doc-content {
  padding: 28px;
}

.doc-content section + section {
  margin-top: 28px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

.doc-content h2 {
  margin: 0 0 12px;
  font-size: 1.35rem;
}

.doc-content p,
.doc-content li {
  color: var(--text-secondary);
}

.doc-content ul,
.doc-content ol {
  margin: 0;
  padding-left: 20px;
}

.doc-content li + li {
  margin-top: 8px;
}

.note,
.highlight-box {
  padding: 16px 18px;
  border-radius: 18px;
  background: var(--primary-soft);
  border: 1px solid rgba(37, 99, 235, 0.16);
  color: var(--text);
}

.note strong,
.highlight-box strong {
  color: var(--text);
}

.info-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 14px;
  overflow: hidden;
  border-radius: 16px;
  border: 1px solid var(--border);
}

.info-table th,
.info-table td {
  text-align: left;
  vertical-align: top;
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
}

.info-table th {
  width: 180px;
  background: rgba(248, 250, 252, 0.95);
  color: var(--text);
  font-weight: 700;
}

.info-table tr:last-child th,
.info-table tr:last-child td {
  border-bottom: none;
}

.footer {
  padding: 0 0 56px;
}

.footer-card {
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
}

.footer-card p {
  margin: 0;
  color: var(--text-secondary);
}

.footer-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.btn-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 18px;
  border-radius: 999px;
  border: 1px solid rgba(37, 99, 235, 0.18);
  background: var(--surface-strong);
  color: var(--primary);
  font-weight: 600;
}

.btn-link:hover {
  text-decoration: none;
  transform: translateY(-1px);
}

@media (max-width: 640px) {
  .hero {
    padding-top: 24px;
  }

  .hero-card,
  .doc-content,
  .footer-card {
    padding: 20px;
  }

  .footer-card {
    flex-direction: column;
    align-items: flex-start;
  }

  .info-table,
  .info-table tbody,
  .info-table tr,
  .info-table th,
  .info-table td {
    display: block;
    width: 100%;
  }

  .info-table th {
    border-bottom: none;
    padding-bottom: 6px;
  }

  .info-table td {
    padding-top: 0;
  }
}