* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: 'Inter', 'Segoe UI', Arial, sans-serif; line-height: 1.7; color: #1a1a2e; background: #f8f9fa; }
a { color: #3b82f6; text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: 960px; margin: 0 auto; padding: 0 20px; }

/* Nav */
.blog-nav { background: #1a1a2e; color: #fff; padding: 14px 0; position: sticky; top: 0; z-index: 100; }
.blog-nav .container { display: flex; justify-content: space-between; align-items: center; }
.blog-nav a { color: #ccc; }
.blog-nav a:hover { color: #fff; text-decoration: none; }
.blog-nav .logo { font-size: 1.3rem; font-weight: 700; color: #fff; }
.blog-nav .nav-links { display: flex; gap: 20px; align-items: center; font-size: .9rem; }
.blog-nav .nav-links a { padding: 4px 0; }
.blog-nav .btn { background: #3b82f6; color: #fff; padding: 6px 16px; border-radius: 6px; font-weight: 600; }
.blog-nav .btn:hover { background: #2563eb; }

/* Page Header */
.page-header { background: linear-gradient(135deg, #1a1a2e, #0f3460); color: #fff; padding: 48px 0; text-align: center; }
.page-header h1 { font-size: 2rem; margin-bottom: 8px; }
.page-header p { color: #94a3b8; font-size: 1rem; }

/* Cards */
.card { background: #fff; border-radius: 10px; box-shadow: 0 1px 4px rgba(0,0,0,.08); padding: 24px; margin-bottom: 16px; transition: box-shadow .2s; }
.card:hover { box-shadow: 0 4px 16px rgba(0,0,0,.12); }
.card-title { font-size: 1.2rem; font-weight: 700; margin-bottom: 6px; }
.card-title a { color: #1a1a2e; }
.card-title a:hover { color: #3b82f6; text-decoration: none; }
.card-meta { font-size: .82rem; color: #888; margin-bottom: 10px; }
.card-meta span { margin-right: 12px; }
.card-text { color: #555; font-size: .92rem; }
.topic-badge { display: inline-block; background: #eef2f7; color: #0f3460; font-size: .75rem; padding: 2px 10px; border-radius: 12px; font-weight: 600; }

/* Grid layouts */
.topics-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 16px; margin-bottom: 32px; }
.topic-card { text-align: center; padding: 28px 20px; }
.topic-card h3 { font-size: 1.1rem; margin-bottom: 4px; }
.topic-card p { font-size: .85rem; color: #888; }
.topic-card .count { font-size: .8rem; color: #3b82f6; font-weight: 600; margin-top: 8px; }

/* Forms */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-weight: 600; margin-bottom: 4px; font-size: .9rem; }
.form-group input, .form-group textarea, .form-group select { width: 100%; padding: 10px 12px; border: 1px solid #d1d5db; border-radius: 6px; font-size: .95rem; font-family: inherit; }
.form-group input:focus, .form-group textarea:focus, .form-group select:focus { outline: none; border-color: #3b82f6; box-shadow: 0 0 0 3px rgba(59,130,246,.15); }
.form-group textarea { min-height: 120px; resize: vertical; }
.btn { display: inline-block; padding: 10px 24px; border-radius: 6px; font-weight: 600; font-size: .95rem; border: none; cursor: pointer; transition: .2s; }
.btn-primary { background: #3b82f6; color: #fff; }
.btn-primary:hover { background: #2563eb; }
.btn-primary:disabled { opacity: .6; cursor: not-allowed; }
.btn-secondary { background: #eef2f7; color: #1a1a2e; }
.btn-secondary:hover { background: #d1d9e6; }
.btn-sm { padding: 6px 14px; font-size: .85rem; }
.btn-danger { background: #ef4444; color: #fff; }
.btn-danger:hover { background: #dc2626; }

/* Auth forms */
.auth-form { max-width: 400px; margin: 40px auto; }
.auth-form .card { padding: 32px; }
.auth-form h2 { text-align: center; margin-bottom: 24px; }
.auth-form .form-footer { text-align: center; margin-top: 16px; font-size: .9rem; color: #666; }

/* Article page */
.article-header { margin-bottom: 24px; }
.article-header h1 { font-size: 1.8rem; margin-bottom: 8px; }
.article-meta { font-size: .85rem; color: #888; margin-bottom: 16px; }
.article-meta span { margin-right: 16px; }
.article-content { font-size: 1rem; line-height: 1.8; color: #333; }
.article-content img { max-width: 100%; height: auto; border-radius: 8px; margin: 16px 0; }
.article-content pre { background: #1a1a2e; color: #e4e4e4; padding: 16px; border-radius: 8px; overflow-x: auto; font-size: .9rem; margin: 12px 0; }
.article-content code { font-family: 'Fira Code', 'Consolas', monospace; font-size: .9rem; }
.article-content pre code { background: none; padding: 0; }
.article-content a { color: #3b82f6; text-decoration: underline; }

/* Replies / Threaded comments */
.reply-thread { margin-top: 8px; }
.reply { padding: 16px; border-left: 3px solid #d1d9e6; margin-bottom: 8px; background: #fafafa; border-radius: 0 8px 8px 0; }
.reply .reply-header { font-size: .82rem; color: #888; margin-bottom: 4px; }
.reply .reply-header strong { color: #1a1a2e; }
.reply .reply-content { font-size: .92rem; color: #333; }
.reply .reply-actions { margin-top: 6px; font-size: .82rem; }
.reply .reply-actions button { background: none; border: none; color: #3b82f6; cursor: pointer; padding: 0; font-size: .82rem; }
.reply .reply-actions button:hover { text-decoration: underline; }
.reply.reply-nested { margin-left: 24px; }
.reply-form { margin-top: 12px; }
.reply-form textarea { width: 100%; padding: 8px 10px; border: 1px solid #d1d5db; border-radius: 6px; font-size: .9rem; min-height: 60px; resize: vertical; font-family: inherit; }
.reply-form textarea:focus { outline: none; border-color: #3b82f6; }

/* Alerts */
.alert { padding: 12px 16px; border-radius: 6px; margin-bottom: 16px; font-size: .9rem; }
.alert-error { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
.alert-success { background: #f0fdf4; color: #166534; border: 1px solid #bbf7d0; }
.alert-info { background: #eff6ff; color: #1e40af; border: 1px solid #bfdbfe; }

/* Empty state */
.empty-state { text-align: center; padding: 60px 20px; color: #888; }
.empty-state h3 { font-size: 1.2rem; margin-bottom: 8px; color: #555; }

/* User badge */
.user-badge { display: inline-flex; align-items: center; gap: 6px; font-size: .82rem; color: #666; }
.user-badge .avatar { width: 22px; height: 22px; border-radius: 50%; background: #3b82f6; color: #fff; display: inline-flex; align-items: center; justify-content: center; font-size: .7rem; font-weight: 700; }

/* Responsive */
@media (max-width: 600px) {
  .blog-nav .nav-links { gap: 10px; font-size: .82rem; }
  .blog-nav .logo { font-size: 1.1rem; }
  .topics-grid { grid-template-columns: 1fr; }
  .page-header h1 { font-size: 1.5rem; }
}