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

:root {
  --accent: #6366f1;
  --accent-light: #eef2ff;
  --text: #1e293b;
  --muted: #64748b;
  --border: #e2e8f0;
  --bg: #f8fafc;
  --white: #ffffff;
  --radius: 12px;
}

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

.container { max-width: 820px; margin: 0 auto; padding: 0 1.5rem; }

/* Header */
header {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 1rem 0;
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.brand { display: flex; align-items: center; gap: 0.75rem; }
.brand-icon { font-size: 1.75rem; }
.brand h1 { font-size: 1.25rem; font-weight: 700; color: var(--text); }
.brand p { font-size: 0.8rem; color: var(--muted); }
nav { display: flex; gap: 1.5rem; }
.nav-link {
  text-decoration: none;
  color: var(--muted);
  font-weight: 500;
  font-size: 0.9rem;
  transition: color 0.15s;
}
.nav-link:hover, .nav-link.active { color: var(--accent); }

/* Hero */
.hero {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  margin: 2rem 0;
}
.hero-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--accent-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  flex-shrink: 0;
}
.hero h2 { font-size: 1.4rem; margin-bottom: 0.4rem; }
.hero p { color: var(--muted); font-size: 0.95rem; }

/* Posts */
.section-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
}
.post-list { display: flex; flex-direction: column; gap: 1rem; margin-bottom: 3rem; }
.post-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  cursor: pointer;
  transition: box-shadow 0.15s, border-color 0.15s;
  text-decoration: none;
  color: inherit;
  display: block;
}
.post-card:hover {
  box-shadow: 0 4px 16px rgba(0,0,0,0.08);
  border-color: var(--accent);
}
.post-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.6rem;
}
.post-category {
  background: var(--accent-light);
  color: var(--accent);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: 99px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.post-date { font-size: 0.82rem; color: var(--muted); }
.post-card h3 { font-size: 1.1rem; margin-bottom: 0.5rem; }
.post-card p { color: var(--muted); font-size: 0.9rem; line-height: 1.5; }
.read-more { color: var(--accent); font-size: 0.85rem; font-weight: 600; margin-top: 0.75rem; display: inline-block; }

/* Post detail */
.post-detail { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 2.5rem; margin: 2rem 0; }
.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--muted);
  font-size: 0.875rem;
  text-decoration: none;
  margin-bottom: 1.5rem;
  cursor: pointer;
  background: none;
  border: none;
  font-family: inherit;
}
.back-btn:hover { color: var(--accent); }
.post-detail h1 { font-size: 1.8rem; margin-bottom: 0.75rem; line-height: 1.3; }
.post-detail .post-meta { margin-bottom: 1.5rem; }
.post-body { color: var(--text); font-size: 1rem; line-height: 1.8; }
.post-body p { margin-bottom: 1rem; }
.post-body h2 { font-size: 1.2rem; margin: 1.5rem 0 0.5rem; }
.post-body ul, .post-body ol { margin: 0.5rem 0 1rem 1.5rem; }
.post-body li { margin-bottom: 0.35rem; }

/* About */
.about-card { background: var(--white); border: 1px solid var(--border); border-radius: var(--radius); padding: 2rem; margin: 2rem 0; }
.about-card h2 { font-size: 1.5rem; margin-bottom: 1rem; }
.about-card p { color: var(--muted); margin-bottom: 0.75rem; }
.social-links { display: flex; gap: 1rem; margin-top: 1.25rem; }
.social-links a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  padding: 0.4rem 1rem;
  border: 1.5px solid var(--accent);
  border-radius: 99px;
  transition: background 0.15s, color 0.15s;
}
.social-links a:hover { background: var(--accent); color: white; }

/* Footer */
footer {
  border-top: 1px solid var(--border);
  padding: 1.5rem 0;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
}

@media (max-width: 600px) {
  .hero { flex-direction: column; text-align: center; }
  .post-detail { padding: 1.5rem; }
}