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

:root {
  --bg: #fafaf8;
  --surface: #ffffff;
  --text: #1a1a1a;
  --text-muted: #6b7280;
  --accent: #2563eb;
  --border: #e5e7eb;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111111;
    --surface: #1c1c1e;
    --text: #f0f0f0;
    --text-muted: #9ca3af;
    --accent: #60a5fa;
    --border: #2d2d2d;
  }
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", "Helvetica Neue",
               "PingFang TC", "Noto Sans TC", sans-serif;
  line-height: 1.75;
  font-size: 16px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  border-bottom: 1px solid var(--border);
  padding: 1rem 1.5rem;
}

.site-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.site-title:hover { color: var(--accent); }

main {
  flex: 1;
  max-width: 720px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem 4rem;
  width: 100%;
}

footer {
  border-top: 1px solid var(--border);
  padding: 1.25rem 1.5rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* Index page header */
.page-header {
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}

.page-subtitle {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-top: 0.25rem;
}

/* Post list */
.post-list { list-style: none; }

.post-item {
  padding: 1.4rem 0;
  border-bottom: 1px solid var(--border);
}

.post-item:last-child { border-bottom: none; }

.post-date {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-family: ui-monospace, "Cascadia Code", monospace;
  letter-spacing: 0.05em;
  margin-bottom: 0.4rem;
}

.post-title { font-size: 1rem; font-weight: 600; }

.post-title a {
  color: var(--text);
  text-decoration: none;
}

.post-title a:hover { color: var(--accent); }

.post-preview {
  margin-top: 0.35rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

/* Individual post */
.back-link {
  display: inline-block;
  margin-bottom: 2rem;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.875rem;
}

.back-link:hover { color: var(--accent); }

.post-header {
  margin-bottom: 2rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border);
}

.post-header h1 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-top: 0.3rem;
  letter-spacing: -0.02em;
}

.post-content ul { list-style: none; padding: 0; }

.post-content ul li {
  padding: 0.4rem 0 0.4rem 1.75rem;
  position: relative;
  font-size: 0.975rem;
}

.post-content ul li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--text-muted);
}

.no-posts {
  color: var(--text-muted);
  font-size: 0.9rem;
  padding: 2rem 0;
}

/* Images in posts */
.post-content img {
  max-width: 100%;
  border-radius: 8px;
  margin: 1rem 0;
  border: 1px solid var(--border);
}

@media (max-width: 600px) {
  main { padding: 1.5rem 1rem 3rem; }
  header { padding: 0.875rem 1rem; }
  .post-header h1 { font-size: 1.25rem; }
}