:root {
  --bg: #f5f6f8;
  --header-bg: #ffffff;
  --card-bg: #ffffff;
  --text: #1a1d23;
  --text-secondary: #8b909a;
  --border: #eceef1;
  --accent: #3b82f6;
  --accent-soft: #eff6ff;
  --shadow: 0 1px 2px rgba(16,24,40,0.05);
  --shadow-hover: 0 6px 16px rgba(16,24,40,0.08);
}

[data-theme="dark"] {
  --bg: #0f1115;
  --header-bg: #16181d;
  --card-bg: #1a1d23;
  --text: #eceef1;
  --text-secondary: #7c828d;
  --border: #262a31;
  --accent: #60a5fa;
  --accent-soft: #1e293b;
  --shadow: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-hover: 0 6px 20px rgba(0,0,0,0.4);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
}

/* 顶部区域 */
.site-header {
  background: var(--header-bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 20;
}

.header-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 32px 12px;
}

.header-top h1 {
  font-size: 19px;
  margin: 0;
  font-weight: 700;
}

.header-actions {
  display: flex;
  gap: 8px;
}

.header-actions button, .header-actions a {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 7px 12px;
  cursor: pointer;
  font-size: 13px;
  text-decoration: none;
  color: var(--text);
}

/* 左侧竖排分类导航 */
.cat-nav {
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  width: 190px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 82px 14px 20px;
  overflow-y: auto;
  overflow-x: hidden;
  scrollbar-width: thin;
  background: var(--header-bg);
  border-right: 1px solid var(--border);
  z-index: 30;
}
.cat-nav::-webkit-scrollbar { display: none; }

.cat-nav-item {
  white-space: nowrap;
  padding: 10px 14px;
  border-radius: 9px;
  font-size: 13.5px;
  color: var(--text-secondary);
  text-decoration: none;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
}

.cat-nav-item:hover {
  background: var(--accent-soft);
  color: var(--text);
}

.cat-nav-item.active {
  background: var(--accent);
  color: #fff;
  font-weight: 600;
}

/* 站内搜索框 */
.search-widget {
  max-width: 900px;
  margin: 28px auto 8px;
  padding: 0 20px;
}

.search-form {
  display: flex;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.search-form input {
  flex: 1;
  border: none;
  outline: none;
  background: transparent;
  padding: 13px 16px;
  font-size: 14px;
  color: var(--text);
}

.search-form button {
  border: none;
  background: var(--accent);
  color: #fff;
  padding: 0 22px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
}

/* 主体内容 */
main {
  max-width: 1200px;
  margin: 0 auto;
  margin-left: 190px;
  padding: 20px 32px 60px;
}

.category {
  margin-bottom: 36px;
  scroll-margin-top: 120px;
}

.category h2 {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
  gap: 12px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px;
  text-decoration: none;
  color: var(--text);
  box-shadow: var(--shadow);
  transition: transform 0.15s, box-shadow 0.15s, border-color 0.15s;
  display: flex;
  gap: 10px;
  align-items: flex-start;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
  border-color: var(--accent);
}

.card img {
  width: 30px;
  height: 30px;
  border-radius: 7px;
  flex-shrink: 0;
  margin-top: 1px;
  background: var(--accent-soft);
  object-fit: cover;
}

.card-title {
  font-weight: 600;
  font-size: 13.5px;
  margin-bottom: 3px;
}

.card-desc {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.loading, .empty {
  color: var(--text-secondary);
  padding: 40px 0;
  text-align: center;
}

.card.hidden { display: none; }

.site-footer {
  text-align: center;
  padding: 24px;
  font-size: 12.5px;
  color: var(--text-secondary);
  border-top: 1px solid var(--border);
}

@media (max-width: 700px) {
  .cat-nav { width: 150px; padding-left: 10px; padding-right: 10px; }
  .header-top { padding-left: 16px; padding-right: 16px; margin-left: 150px; }
  main { margin-left: 150px; padding-left: 16px; padding-right: 16px; }
  .search-widget { margin-left: 150px; }
}