:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --gradient: linear-gradient(135deg, #6366f1, #8b5cf6);
  --bg: #f5f6fa;
  --card: #ffffff;
  --text: #1f2937;
  --text-light: #6b7280;
  --border: #e5e7eb;
  --radius: 12px;
  --shadow: 0 2px 12px rgba(0,0,0,.06);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

.container { max-width: 960px; margin: 0 auto; padding: 0 20px; }

/* ===== Header ===== */
.site-header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 100;
}
.header-inner {
  display: flex; align-items: center; gap: 20px;
  padding: 14px 20px; flex-wrap: wrap;
}
.logo a {
  font-size: 1.5rem; font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
  text-decoration: none;
}
.main-nav { display: flex; gap: 4px; flex: 1; flex-wrap: wrap; }
.main-nav a {
  padding: 6px 12px; border-radius: 8px;
  color: var(--text); text-decoration: none; font-size: .95rem;
  transition: background .2s;
}
.main-nav a:hover { background: #eef2ff; }
.main-nav a.active { background: var(--gradient); color: #fff; }
.search-form { display: flex; gap: 8px; }
.search-form input {
  padding: 8px 14px; border: 1px solid var(--border);
  border-radius: 20px; font-size: .9rem; width: 180px;
  outline: none; transition: border .2s;
}
.search-form input:focus { border-color: var(--primary); }
.search-form button {
  padding: 8px 16px; border: 0; border-radius: 20px;
  background: var(--gradient); color: #fff; cursor: pointer;
  font-size: .9rem;
}
.search-form button:hover { filter: brightness(1.1); }

/* ===== Main ===== */
.site-main { padding: 30px 20px; min-height: 60vh; }
.section-title { font-size: 1.3rem; margin: 24px 0 16px; }
.section-title:first-child { margin-top: 0; }

/* ===== Article Card ===== */
.article-list { display: flex; flex-direction: column; gap: 16px; }
.article-card {
  background: var(--card); border-radius: var(--radius);
  box-shadow: var(--shadow); overflow: hidden;
  transition: transform .2s, box-shadow .2s;
}
.article-card:hover { transform: translateY(-2px); box-shadow: 0 6px 24px rgba(0,0,0,.1); }
.article-card.pinned { border-left: 4px solid #f59e0b; }
.card-cover img { width: 100%; height: 200px; object-fit: cover; }
.card-body { padding: 20px; }
.card-head { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }
.card-category a {
  font-size: .8rem; padding: 3px 10px; border-radius: 12px;
  background: #eef2ff; color: var(--primary); text-decoration: none;
}
.card-category--none { font-size: .8rem; color: var(--text-light); }
.card-badge {
  font-size: .7rem; padding: 2px 8px; border-radius: 10px;
  background: #fef3c7; color: #b45309; font-weight: 600;
}
.card-title a {
  font-size: 1.15rem; font-weight: 700; color: var(--text);
  text-decoration: none; line-height: 1.5;
}
.card-title a:hover { color: var(--primary); }
.card-summary { color: var(--text-light); font-size: .92rem; margin: 8px 0 12px; }
.card-meta { display: flex; align-items: center; gap: 8px; font-size: .82rem; color: var(--text-light); flex-wrap: wrap; }
.meta-sep { opacity: .4; }
.tag-pill {
  font-size: .78rem; padding: 2px 8px; border-radius: 10px;
  background: #f0fdf4; color: #16a34a; text-decoration: none;
}
.tag-pill:hover { background: #dcfce7; }

/* ===== Article Detail ===== */
.article-detail { background: var(--card); border-radius: var(--radius); box-shadow: var(--shadow); padding: 30px; margin-bottom: 20px; }
.detail-cover img { width: 100%; max-height: 400px; object-fit: cover; border-radius: 8px; margin-bottom: 20px; }
.detail-header h1 { font-size: 1.8rem; margin-bottom: 10px; }
.detail-meta { display: flex; align-items: center; gap: 12px; font-size: .88rem; color: var(--text-light); flex-wrap: wrap; }
.detail-category { padding: 3px 10px; border-radius: 12px; background: #eef2ff; color: var(--primary); text-decoration: none; font-size: .82rem; }
.detail-content { margin: 24px 0; line-height: 1.85; }
.detail-content h2 { font-size: 1.3rem; margin: 24px 0 12px; }
.detail-content p { margin-bottom: 14px; }
.detail-content pre { background: #f8fafc; border: 1px solid var(--border); border-radius: 8px; padding: 16px; overflow-x: auto; font-size: .88rem; }
.detail-content code { background: #f1f5f9; padding: 2px 6px; border-radius: 4px; font-size: .9em; }
.detail-content pre code { background: none; padding: 0; }
.detail-content blockquote { border-left: 3px solid var(--primary); padding: 12px 16px; margin: 16px 0; background: #f8f7ff; border-radius: 0 8px 8px 0; }
.detail-content ul, .detail-content ol { padding-left: 24px; margin-bottom: 14px; }
.detail-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 24px; padding-top: 16px; border-top: 1px solid var(--border); }
.back-link { display: inline-block; margin-top: 16px; color: var(--primary); text-decoration: none; font-size: .95rem; }
.back-link:hover { text-decoration: underline; }

/* ===== Tag Cloud ===== */
.tag-cloud { display: flex; flex-wrap: wrap; gap: 12px; padding: 10px 0; }
.tag-cloud-item {
  padding: 8px 16px; border-radius: 20px; background: var(--card);
  box-shadow: var(--shadow); color: var(--text); text-decoration: none;
  transition: background .2s;
}
.tag-cloud-item:hover { background: #eef2ff; color: var(--primary); }
.search-count { color: var(--text-light); font-size: .9rem; margin-bottom: 16px; }
.search-empty-tip { color: var(--text-light); font-size: .95rem; padding: 40px 0; text-align: center; }

/* ===== Empty State ===== */
.empty-state { text-align: center; padding: 50px 0; color: var(--text-light); }
.empty-icon { font-size: 3rem; margin-bottom: 12px; }

/* ===== Pagination ===== */
.pagination { margin-top: 30px; text-align: center; }
.pagination ul { list-style: none; display: inline-flex; gap: 4px; }
.pagination a, .pagination span {
  display: inline-block; padding: 8px 14px; border-radius: 8px;
  font-size: .9rem; text-decoration: none;
  background: var(--card); box-shadow: var(--shadow); color: var(--text);
}
.pagination a:hover { background: var(--primary); color: #fff; }
.pagination .active span { background: var(--gradient); color: #fff; }

/* ===== Footer ===== */
.site-footer {
  background: var(--card); border-top: 1px solid var(--border);
  padding: 24px 20px; text-align: center; font-size: .85rem; color: var(--text-light);
}
.footer-meta { margin-top: 6px; font-size: .8rem; opacity: .6; }

/* ===== Flash ===== */
.flash { padding: 12px 18px; border-radius: 8px; margin-bottom: 16px; font-size: .9rem; }
.flash-success { background: #f0fdf4; color: #16a34a; border: 1px solid #bbf7d0; }
.flash-error { background: #fef2f2; color: #dc2626; border: 1px solid #fecaca; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .header-inner { flex-direction: column; align-items: flex-start; gap: 10px; }
  .main-nav { width: 100%; }
  .search-form { width: 100%; }
  .search-form input { flex: 1; width: auto; }
  .article-detail { padding: 16px; }
  .detail-header h1 { font-size: 1.4rem; }
}
@media (max-width: 480px) {
  .card-body { padding: 14px; }
  .main-nav a { padding: 4px 8px; font-size: .85rem; }
}

/* ===== Ad Slots ===== */
.ad-slot {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin: 20px 0;
    padding: 16px;
    text-align: center;
}
.ad-slot-title {
    font-size: .8rem;
    color: var(--text-light);
    margin-bottom: 8px;
    letter-spacing: .05em;
}
.ad-image {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    display: inline-block;
}