:root {
  --bg: #fafafa;
  --fg: #16181d;
  --muted: #6b7280;
  --card: #ffffff;
  --border: #e5e7eb;
  --accent: #4f46e5;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --fg: #e8eaee;
    --muted: #9099a8;
    --card: #171a21;
    --border: #262b35;
    --accent: #818cf8;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
}
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 20px; }
header { padding: 72px 0 32px; }
h1 { margin: 0 0 8px; font-size: clamp(2rem, 5vw, 3rem); letter-spacing: -0.02em; }
.tagline { margin: 0 0 20px; color: var(--muted); font-size: 1.1rem; }
.links a { margin-right: 16px; color: var(--accent); text-decoration: none; }
.links a:hover { text-decoration: underline; }
.filters { display: flex; flex-wrap: wrap; gap: 8px; margin: 24px 0; }
.filters button {
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--fg);
  padding: 6px 14px;
  border-radius: 999px;
  cursor: pointer;
  font: inherit;
  font-size: 0.9rem;
}
.filters button[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: #fff; }
.grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); padding-bottom: 64px; }
.card {
  display: flex; flex-direction: column; gap: 8px;
  padding: 20px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  color: inherit;
  text-decoration: none;
  transition: transform .15s, border-color .15s, box-shadow .15s;
}
.card:hover, .card:focus-visible { transform: translateY(-3px); border-color: var(--accent); box-shadow: 0 8px 24px rgba(0,0,0,.08); }
.card .cat { font-size: .8rem; color: var(--accent); }
.card h2 { margin: 0; font-size: 1.15rem; }
.card p { margin: 0; color: var(--muted); flex: 1; }
.card .tags { display: flex; flex-wrap: wrap; gap: 6px; }
.card .tags span { font-size: .75rem; padding: 2px 8px; border-radius: 6px; background: var(--bg); border: 1px solid var(--border); color: var(--muted); }
footer { padding: 24px 0 48px; color: var(--muted); font-size: .85rem; border-top: 1px solid var(--border); }