:root {
  --color-bg: #ffffff;
  --color-text: #1a1a1a;
  --color-muted: #666666;
  --color-accent: #0066cc;
  --color-border: #e1e4e8;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;
}

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

body {
  font-family: var(--font-sans);
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  border-bottom: 1px solid var(--color-border);
  padding: 20px 0;
  margin-bottom: 40px;
}

.site-header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.site-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
}

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

.site-nav a {
  margin-left: 20px;
  color: var(--color-muted);
  text-decoration: none;
  font-size: 0.95rem;
}

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

/* Main content */
.main-content {
  min-height: 60vh;
}

.post-title {
  font-size: 2rem;
  margin-bottom: 10px;
  line-height: 1.2;
}

.post-meta {
  color: var(--color-muted);
  font-size: 0.9rem;
  margin-bottom: 30px;
}

.post-content {
  font-size: 1.05rem;
  line-height: 1.7;
}

.post-content h2 {
  margin-top: 40px;
  margin-bottom: 15px;
  font-size: 1.5rem;
}

.post-content h3 {
  margin-top: 30px;
  margin-bottom: 10px;
  font-size: 1.25rem;
}

.post-content p {
  margin-bottom: 20px;
}

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

.post-content a:hover {
  text-decoration: underline;
}

.post-content code {
  font-family: var(--font-mono);
  background: #f4f4f4;
  padding: 2px 6px;
  border-radius: 3px;
  font-size: 0.9em;
}

.post-content pre {
  background: #f4f4f4;
  padding: 15px;
  border-radius: 5px;
  overflow-x: auto;
  margin-bottom: 20px;
}

.post-content pre code {
  background: none;
  padding: 0;
  font-size: 0.85rem;
}

.post-content blockquote {
  border-left: 4px solid var(--color-accent);
  padding-left: 20px;
  margin: 20px 0;
  color: var(--color-muted);
  font-style: italic;
}

.post-content ul, .post-content ol {
  margin-bottom: 20px;
  padding-left: 30px;
}

.post-content li {
  margin-bottom: 8px;
}

.post-tags {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--color-border);
}

.tag {
  display: inline-block;
  background: var(--color-border);
  color: var(--color-muted);
  padding: 4px 10px;
  border-radius: 3px;
  font-size: 0.8rem;
  margin-right: 8px;
  margin-bottom: 8px;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 30px 0;
  margin-top: 60px;
  color: var(--color-muted);
  font-size: 0.9rem;
}

.site-footer .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-nav a {
  margin-left: 15px;
  color: var(--color-muted);
  text-decoration: none;
}

.footer-nav a:hover {
  color: var(--color-accent);
}

/* Utility */
.text-center {
  text-align: center;
}

.mt-20 {
  margin-top: 20px;
}

.mb-20 {
  margin-bottom: 20px;
}

/* Responsive */
@media (max-width: 600px) {
  .site-header .container {
    flex-direction: column;
    align-items: flex-start;
  }

  .site-nav {
    margin-top: 10px;
  }

  .site-nav a {
    margin-left: 0;
    margin-right: 15px;
  }

  .post-title {
    font-size: 1.5rem;
  }

  .site-footer .container {
    flex-direction: column;
    text-align: center;
  }

  .footer-nav {
    margin-top: 10px;
  }

  .footer-nav a {
    margin: 0 8px;
  }
}