:root {
  --bg: #ffffff;
  --text: #1a1a1a;
  --text-secondary: #6b7280;
  --border: #e5e7eb;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --card-bg: #f9fafb;
  --code-bg: #f3f4f6;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

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

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

/* Navigation */
nav {
  position: sticky;
  top: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  z-index: 100;
}

nav .container {
  max-width: 720px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

nav .logo {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text);
}

nav .links {
  display: flex;
  gap: 1.5rem;
}

nav .links a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  transition: color 0.2s;
}

nav .links a:hover,
nav .links a.active {
  color: var(--text);
}

/* Main content */
main {
  max-width: 720px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

/* About section */
.about {
  margin-bottom: 4rem;
}

.about-header {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.about-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  object-fit: cover;
}

.about-name {
  font-size: 1.8rem;
  font-weight: 700;
}

.about-links {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.about-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: all 0.2s;
}

.about-links a:hover {
  color: var(--text);
  border-color: var(--text-secondary);
}

.about-bio {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* Posts section */
.section-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
}

.posts-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.post-card {
  padding: 1.25rem;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  transition: box-shadow 0.2s;
}

.post-card:hover {
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}

.post-card a {
  font-weight: 600;
  font-size: 1.05rem;
}

.post-date {
  display: block;
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 0.3rem;
}

.post-summary {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 0.5rem;
}

/* Post detail page */
.post-detail {
  margin-top: 1rem;
}

.post-detail-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.post-detail-date {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.post-content {
  line-height: 1.8;
}

.post-content h1,
.post-content h2,
.post-content h3,
.post-content h4 {
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  font-weight: 600;
}

.post-content h1 {
  font-size: 1.5rem;
}

.post-content h2 {
  font-size: 1.3rem;
}

.post-content h3 {
  font-size: 1.1rem;
}

.post-content p {
  margin-bottom: 1rem;
}

.post-content a {
  color: var(--accent);
  text-decoration: underline;
}

.post-content img {
  max-width: 100%;
  border-radius: 8px;
  margin: 1rem 0;
}

.post-content code {
  background: var(--code-bg);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-size: 0.9em;
  font-family: "SF Mono", Monaco, Consolas, monospace;
}

.post-content pre {
  background: var(--code-bg);
  padding: 1rem;
  border-radius: 8px;
  overflow-x: auto;
  margin-bottom: 1rem;
}

.post-content pre code {
  background: none;
  padding: 0;
}

.post-content blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 1rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.post-content ul,
.post-content ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

.post-content li {
  margin-bottom: 0.3rem;
}

/* Loading & error states */
.loading,
.error {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-secondary);
}

.error {
  color: #dc2626;
}

/* Footer */
footer {
  max-width: 720px;
  margin: 4rem auto 0;
  padding: 1.5rem;
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

/* Pagination */
.pagination {
  margin-top: 2rem;
}

.pagination-controls {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.pagination-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: all 0.2s;
}

.pagination-btn:hover {
  color: var(--text);
  border-color: var(--text-secondary);
}

.pagination-btn.active {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

/* Responsive */
@media (max-width: 600px) {
  .about-header {
    flex-direction: column;
    text-align: center;
  }

  .about-links {
    justify-content: center;
  }

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