body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.5rem;
  line-height: 1.7;
  color: #1e293b;
  background: #f8fafc;
}

/* Header */
header {
  padding: 1.5rem 0;
  border-bottom: 1px solid #e2e8f0;
  margin-bottom: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

header h1 {
  margin: 0;
  font-size: 1.3rem;
}

header h1 a {
  color: #0f172a;
  text-decoration: none;
  font-weight: 700;
}

header nav a {
  margin-left: 1.5rem;
  color: #475569;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
}

header nav a:hover {
  color: #1e293b;
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 3rem 1rem 2.5rem;
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  border-radius: 12px;
  margin: 1.5rem 0 2.5rem;
  color: #f1f5f9;
}

.hero h1 {
  font-size: 2.2rem;
  margin: 0 0 0.8rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: #ffffff;
  text-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.hero .tagline {
  font-size: 1.15rem;
  color: #f1f5f9;
  font-weight: 500;
  max-width: 600px;
  margin: 0 auto 1rem;
  line-height: 1.6;
}

.hero .about-text {
  font-size: 0.95rem;
  color: #f1f5f9;
  max-width: 650px;
  margin: 0 auto;
  line-height: 1.7;
  padding: 0 1rem;
}

.hero .topics {
  margin-top: 1rem;
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

.hero .topic-tag {
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.2);
  padding: 0.3rem 0.8rem;
  border-radius: 20px;
  font-size: 0.8rem;
  color: #cbd5e1;
}

/* Post Grid */
.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.post-card {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 10px;
  overflow: hidden;
  transition: transform 0.15s, box-shadow 0.15s;
}

.post-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

.post-card-image {
  width: 100%;
  height: 160px;
  background: #f1f5f9;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.post-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.post-card-body {
  padding: 1.2rem;
}

.post-card-body h2 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
  line-height: 1.4;
}

.post-card-body h2 a {
  color: #0f172a;
  text-decoration: none;
}

.post-card-body h2 a:hover {
  color: #2563eb;
}

.post-card-body .meta {
  font-size: 0.8rem;
  color: #94a3b8;
  margin-bottom: 0.5rem;
}

.post-card-body .excerpt {
  font-size: 0.85rem;
  color: #64748b;
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* Section titles */
.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #0f172a;
  margin: 2rem 0 0.5rem;
  letter-spacing: -0.01em;
}

.section-subtitle {
  color: #64748b;
  font-size: 0.95rem;
  margin: 0 0 1rem;
}

/* Standard content */
main h1 { font-size: 1.8rem; font-weight: 700; color: #0f172a; }
main img { max-width: 100%; height: auto; border-radius: 8px; margin: 1.5rem 0; }
article { margin-bottom: 2.5rem; }
article h1 { font-size: 1.6rem; }
article time { color: #94a3b8; font-size: 0.85rem; display: block; margin-bottom: 1rem; }
article h2 { font-size: 1.3rem; margin-top: 2rem; color: #0f172a; }
article h3 { font-size: 1.1rem; margin-top: 1.5rem; }
article p, article li { color: #334155; }
article a { color: #2563eb; }

/* Tables */
article table { width: 100%; border-collapse: collapse; margin: 1.5rem 0; font-size: 0.9rem; }
article th, article td { padding: 0.6rem 0.8rem; border: 1px solid #e2e8f0; text-align: left; }
article th { background: #f1f5f9; font-weight: 600; color: #0f172a; }

/* Code blocks */
article code { background: #f1f5f9; padding: 0.15rem 0.4rem; border-radius: 4px; font-size: 0.85rem; }
article pre code { background: none; padding: 0; }
article pre {
  background: #1e293b;
  color: #e2e8f0;
  padding: 1rem;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.5;
}

/* Blockquotes */
article blockquote {
  border-left: 4px solid #2563eb;
  padding: 0.5rem 1rem;
  margin: 1.5rem 0;
  background: #f1f5f9;
  border-radius: 0 8px 8px 0;
  color: #475569;
  font-style: italic;
}

/* Lists */
article ol, article ul { padding-left: 1.5rem; }
article li { margin-bottom: 0.3rem; }

/* Back link */
.back-link {
  display: inline-block;
  color: #64748b;
  text-decoration: none;
  font-size: 0.9rem;
  margin-bottom: 1rem;
}
.back-link:hover { color: #0f172a; }

/* Footer */
footer {
  text-align: center;
  padding: 2rem 0;
  border-top: 1px solid #e2e8f0;
  margin-top: 3rem;
  color: #64748b;
  font-size: 0.85rem;
}

/* Pagination */
.pagination {
  text-align: center;
  padding: 1rem 0;
  color: #94a3b8;
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 640px) {
  .hero h1 { font-size: 1.6rem; }
  .posts-grid { grid-template-columns: 1fr; }
  header { flex-direction: column; gap: 0.5rem; }
  header nav a { margin: 0 0.75rem; }
}

/* Post list pages (e.g., /posts/) */
.post-list article {
  padding: 1.2rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 10px;
  margin-bottom: 1rem;
}

.post-list article h2 { margin: 0 0 0.3rem; font-size: 1.1rem; }
.post-list article h2 a { color: #0f172a; text-decoration: none; }
.post-list article h2 a:hover { color: #2563eb; }
.post-list article .meta { font-size: 0.8rem; color: #94a3b8; }
.post-list article p { font-size: 0.9rem; color: #64748b; margin: 0.5rem 0 0; }