:root {
  --bg: #ffffff;
  --text: #16161a;
  --muted: #6b6b76;
  --card: #f4f4f6;
  --line: #e4e4e8;
  --accent: #111111;
  --accent-text: #ffffff;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111113;
    --text: #ececf0;
    --muted: #9a9aa5;
    --card: #1c1c20;
    --line: #2a2a30;
    --accent: #ececf0;
    --accent-text: #111113;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}
a { color: inherit; }
.wrap { max-width: 880px; margin: 0 auto; padding: 0 20px; }
header.top { display: flex; align-items: center; gap: 10px; padding: 20px 0; }
header.top img { width: 32px; height: 32px; border-radius: 8px; }
header.top a { text-decoration: none; font-weight: 600; font-size: 18px; display: flex; align-items: center; gap: 10px; }
.hero { padding: 48px 0 32px; }
.hero h1 { font-size: 36px; line-height: 1.25; margin: 0 0 16px; }
.hero p { color: var(--muted); font-size: 18px; margin: 0 0 28px; max-width: 640px; }
.buttons { display: flex; flex-wrap: wrap; gap: 12px; }
.button {
  display: inline-block; padding: 12px 20px; border-radius: 10px; text-decoration: none; font-weight: 600;
  background: var(--accent); color: var(--accent-text); border: 1px solid var(--accent);
}
.button.secondary { background: transparent; color: var(--text); border-color: var(--line); }
.small { color: var(--muted); font-size: 14px; margin-top: 12px; }
section { padding: 28px 0; border-top: 1px solid var(--line); }
section h2 { font-size: 22px; margin: 0 0 12px; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 14px; }
.card { background: var(--card); border-radius: 12px; padding: 18px; }
.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
article { padding: 24px 0 40px; }
article h1 { font-size: 28px; margin: 8px 0 4px; }
article h2 { font-size: 19px; margin: 28px 0 8px; }
article p, article li { color: var(--text); }
article .meta { color: var(--muted); font-size: 14px; }
footer { border-top: 1px solid var(--line); padding: 24px 0 40px; color: var(--muted); font-size: 14px; }
footer .links { display: flex; flex-wrap: wrap; gap: 8px 18px; }
footer a { text-decoration: none; }
footer a:hover { text-decoration: underline; }
@media (max-width: 560px) {
  .hero h1 { font-size: 28px; }
  .hero p { font-size: 16px; }
}