/* AI 每日快报 — clean, mobile-first */
:root {
  --ink: #1a1a2e;
  --muted: #6b7280;
  --accent: #4f46e5;
  --accent-soft: #eef2ff;
  --hairline: #e5e7eb;
  --bg: #ffffff;
  --card: #fafafa;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC",
    "Hiragana Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  font-size: 17px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}
.wrap { max-width: 720px; margin: 0 auto; padding: 0 20px; }

.site-header {
  border-bottom: 1px solid var(--hairline);
  background: rgba(255,255,255,.92);
  position: sticky; top: 0; z-index: 10;
  backdrop-filter: blur(8px);
}
.site-header .wrap {
  display: flex; align-items: center; justify-content: space-between;
  padding-top: 12px; padding-bottom: 12px;
}
.brand {
  font-size: 20px; font-weight: 800; color: var(--ink);
  text-decoration: none; letter-spacing: .02em;
}
.brand .logo { margin-right: 6px; }
.site-header nav a {
  color: var(--muted); text-decoration: none;
  margin-left: 18px; font-size: 15px;
}
.site-header nav a:hover { color: var(--accent); }

.hero { padding: 34px 0 6px; }
.hero h1 { font-size: 26px; margin: 0 0 6px; letter-spacing: .02em; }
.hero .date { font-size: 15px; color: var(--muted); font-weight: 400; }
.tagline { color: var(--muted); margin: 0 0 8px; font-size: 15px; }

.page-title { font-size: 24px; margin: 30px 0 4px; }
.issue-date { color: var(--muted); font-size: 14px; margin: 0 0 18px; }

.news-item {
  background: var(--card);
  border: 1px solid var(--hairline);
  border-radius: 14px;
  padding: 20px 22px;
  margin: 18px 0;
}
.news-item h2 { font-size: 19px; line-height: 1.5; margin: 8px 0 10px; }
.news-item p { margin: 8px 0; color: #374151; font-size: 16px; }
.news-tag {
  display: inline-block;
  font-size: 13px; font-weight: 700;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 999px;
  padding: 2px 12px;
}
.sources { font-size: 13px; color: var(--muted); margin-top: 10px; }
.sources a { color: var(--muted); text-decoration: underline; text-underline-offset: 3px; }
.news-item a { color: var(--accent); }

.archive { margin: 44px 0 30px; }
.archive h2 { font-size: 20px; border-bottom: 2px solid var(--ink); padding-bottom: 8px; }
.archive ul { list-style: none; padding: 0; margin: 0; }
.archive li {
  display: flex; justify-content: space-between; align-items: baseline;
  padding: 12px 2px; border-bottom: 1px solid var(--hairline);
}
.archive li a { color: var(--ink); text-decoration: none; font-weight: 600; }
.archive li a:hover { color: var(--accent); }
.archive li span { color: var(--muted); font-size: 13px; white-space: nowrap; }

.site-footer {
  border-top: 1px solid var(--hairline);
  margin-top: 40px; padding: 22px 0 40px;
  color: var(--muted); font-size: 14px;
}
.site-footer .tiny { font-size: 12px; margin-top: 4px; }

/* columns */
.col-nav { margin: 6px 0 10px; font-size: 15px; }
.col-nav a { color: var(--accent); text-decoration: none; font-weight: 600; }
.column { margin: 34px 0 10px; padding-top: 8px; border-top: 2px solid var(--ink); }
.col-head h2 { font-size: 22px; margin: 0 0 2px; }
.col-desc { color: var(--muted); font-size: 14px; }
.trend-note { color: var(--muted); font-size: 13px; }
ol.trend-list { list-style: none; padding: 0; margin: 14px 0; counter-reset: tr; }
ol.trend-list li {
  padding: 9px 2px; border-bottom: 1px solid var(--hairline);
  font-size: 16px; display: flex; align-items: baseline; gap: 12px;
}
ol.trend-list .rank {
  flex: none; width: 30px; height: 30px; line-height: 30px; text-align: center;
  font-size: 13px; font-weight: 800; color: var(--accent);
  background: var(--accent-soft); border-radius: 8px;
}
ol.trend-list li:nth-child(-n+3) .rank { background: var(--accent); color: #fff; }
.note { font-size: 13px; color: var(--muted); margin-top: 8px; }

@media (max-width: 520px) {
  body { font-size: 16px; }
  .news-item { padding: 16px; }
  .hero h1 { font-size: 22px; }
}