:root {
  --bg: #fafafa;
  --fg: #1a1a1a;
  --muted: #666;
  --accent: #2563eb;
  --card-bg: #fff;
  --card-border: #e5e7eb;
  --code-bg: #282a36;
  --max-w: 720px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f0f0f;
    --fg: #e5e5e5;
    --muted: #999;
    --accent: #60a5fa;
    --card-bg: #1a1a1a;
    --card-border: #333;
  }
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, "Noto Sans SC", "PingFang SC", sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-header {
  padding: 2rem 1rem;
  text-align: center;
  border-bottom: 1px solid var(--card-border);
}

.site-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--fg);
  text-decoration: none;
}

main {
  flex: 1;
  max-width: var(--max-w);
  width: 100%;
  margin: 0 auto;
  padding: 2rem 1rem;
}

footer {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--card-border);
}

/* Index */
.post-list { display: flex; flex-direction: column; gap: 1rem; }

.post-card a {
  display: block;
  padding: 1.25rem;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 8px;
  text-decoration: none;
  color: inherit;
  transition: border-color .15s;
}
.post-card a:hover { border-color: var(--accent); }
.post-card h2 { font-size: 1.2rem; margin-bottom: .25rem; }
.post-card time { font-size: .85rem; color: var(--muted); }
.post-card p { margin-top: .5rem; color: var(--muted); }

.empty { text-align: center; color: var(--muted); padding: 4rem 0; }

/* Post */
.post h1 { font-size: 1.8rem; margin-bottom: .25rem; }
.post > time { display: block; color: var(--muted); font-size: .9rem; margin-bottom: 2rem; }

.post-body h2 { font-size: 1.4rem; margin: 2rem 0 .75rem; }
.post-body h3 { font-size: 1.15rem; margin: 1.5rem 0 .5rem; }
.post-body p { margin-bottom: 1rem; }
.post-body a { color: var(--accent); }
.post-body img { max-width: 100%; border-radius: 6px; margin: 1rem 0; }
.post-body blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 1rem;
  color: var(--muted);
  margin: 1rem 0;
}
.post-body pre {
  background: var(--code-bg);
  color: #f8f8f2;
  padding: 1rem;
  border-radius: 6px;
  overflow-x: auto;
  margin: 1rem 0;
  font-size: .9rem;
}
.post-body code {
  font-family: "JetBrains Mono", "Fira Code", monospace;
  font-size: .9em;
}
.post-body :not(pre) > code {
  background: var(--card-border);
  padding: .15em .35em;
  border-radius: 3px;
}
.post-body ul, .post-body ol { padding-left: 1.5rem; margin-bottom: 1rem; }
.post-body li { margin-bottom: .25rem; }
.post-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  overflow-x: auto;
  display: block;
}
.post-body th, .post-body td {
  padding: .5rem .75rem;
  border: 1px solid var(--card-border);
  text-align: left;
}
.post-body th { background: var(--card-bg); font-weight: 600; }

.back {
  display: inline-block;
  margin-top: 2rem;
  color: var(--accent);
  text-decoration: none;
}
.back:hover { text-decoration: underline; }