:root {
  --bg: #f6f7fb;
  --surface: #ffffff;
  --surface-soft: #f8fafc;
  --text: #162033;
  --text-secondary: #5b6679;
  --line: #e6ebf2;
  --accent: #22324a;
  --accent-soft: #eef3f8;
  --max-width: 920px;
  --radius-lg: 24px;
  --radius-md: 18px;
  --shadow: 0 12px 32px rgba(15, 23, 42, 0.06);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, #ffffff 0, #f8fafc 28%, #f6f7fb 100%);
  line-height: 1.75;
}

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

a:hover {
  text-decoration: underline;
}

.page {
  width: min(100%, var(--max-width));
  margin: 0 auto;
  padding: 40px 20px 56px;
}

.hero {
  padding: 28px;
  background: linear-gradient(180deg, #ffffff 0%, #fbfcfe 100%);
  border: 1px solid var(--line);
  border-radius: 28px;
  box-shadow: var(--shadow);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
}

.hero h1 {
  margin: 16px 0 8px;
  font-size: clamp(28px, 4vw, 40px);
  line-height: 1.18;
}

.hero p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 15px;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.chip {
  padding: 7px 12px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--line);
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 600;
}

.section {
  margin-top: 18px;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
}

.section h2 {
  margin: 0 0 14px;
  font-size: 22px;
}

.section h3 {
  margin: 22px 0 10px;
  font-size: 17px;
}

.section p,
.section li {
  color: var(--text-secondary);
  font-size: 15px;
}

.section ul,
.section ol {
  margin: 10px 0 0;
  padding-left: 22px;
}

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

.nav-card {
  display: block;
  padding: 20px;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, #ffffff 0%, #fafbfd 100%);
  transition: transform 160ms ease, box-shadow 160ms ease, border-color 160ms ease;
}

.nav-card:hover {
  transform: translateY(-2px);
  border-color: #d4dce8;
  box-shadow: 0 12px 28px rgba(15, 23, 42, 0.08);
  text-decoration: none;
}

.nav-card h3 {
  margin: 0 0 8px;
  color: var(--text);
}

.nav-card p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 14px;
}

.list-box {
  padding: 16px 18px;
  border-radius: var(--radius-md);
  background: var(--surface-soft);
  border: 1px solid var(--line);
}

.footer {
  margin-top: 18px;
  color: var(--text-secondary);
  font-size: 13px;
  text-align: center;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 10px;
  font-size: 14px;
  font-weight: 700;
}

@media (max-width: 640px) {
  .page {
    padding: 20px 14px 36px;
  }

  .hero,
  .section {
    padding: 18px;
    border-radius: 20px;
  }
}