:root {
  --bg: #f7f5f0;
  --surface: #ffffff;
  --text: #2c2c2c;
  --muted: #6b6b6b;
  --accent: #c45c26;
  --accent-soft: #fdf0e8;
  --border: #e8e4dc;
  --max: 720px;
  --wide: 960px;
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  line-height: 1.75;
  color: var(--text);
}

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

body {
  background: var(--bg);
  min-height: 100vh;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}

.header-inner {
  max-width: var(--wide);
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: 0.05em;
}

.logo span { color: var(--accent); }

nav { display: flex; gap: 1.25rem; font-size: 0.95rem; }
nav a { color: var(--muted); }
nav a.active, nav a:hover { color: var(--accent); text-decoration: none; }

main {
  max-width: var(--wide);
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

.hero {
  background: linear-gradient(135deg, var(--accent-soft) 0%, var(--surface) 60%);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 2.5rem 2rem;
  margin-bottom: 2.5rem;
}

.hero h1 {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}

.hero .tagline {
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 36em;
}

.section-title {
  font-size: 1.1rem;
  color: var(--muted);
  margin-bottom: 1rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.article-list { list-style: none; display: grid; gap: 1rem; }

.article-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem 1.5rem;
  transition: box-shadow 0.2s;
}

.article-card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.article-card h2 { font-size: 1.15rem; margin-bottom: 0.35rem; }
.article-card h2 a { color: var(--text); }
.article-card h2 a:hover { color: var(--accent); }

.meta {
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.article-card p { color: var(--muted); font-size: 0.95rem; }

.article-body {
  max-width: var(--max);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem 2rem 2.5rem;
}

.article-body h1 { font-size: 1.75rem; margin-bottom: 0.5rem; }
.article-body .meta { margin-bottom: 1.5rem; padding-bottom: 1rem; border-bottom: 1px solid var(--border); }
.article-body h2 { font-size: 1.2rem; margin: 1.75rem 0 0.75rem; color: var(--text); }
.article-body p { margin-bottom: 1rem; }
.article-body ul, .article-body ol { margin: 0 0 1rem 1.25rem; }
.article-body li { margin-bottom: 0.35rem; }
.article-body code {
  background: var(--accent-soft);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  font-size: 0.9em;
}

.back-link {
  display: inline-block;
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
}

.site-footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  padding: 2rem 1.5rem;
  text-align: center;
  color: var(--muted);
  font-size: 0.875rem;
}

.site-footer p + p { margin-top: 0.5rem; }

.about-grid {
  display: grid;
  gap: 1.5rem;
}

.about-grid .article-body { max-width: none; }

@media (max-width: 600px) {
  .header-inner { flex-direction: column; align-items: flex-start; }
  .hero h1 { font-size: 1.5rem; }
}