/* ============================================
   国学紫微研习社 · 设计系统
   参考: ziweidoushustudy.com 风格
   白色背景 + 清新绿色 + 现代简洁
   ============================================ */

/* ---- 全局变量 ---- */
:root {
  --green-primary:   #29d467;
  --green-dark:      #1ab855;
  --green-light:     #e8faf0;
  --green-mid:       #c2f0d4;
  --bg-white:        #ffffff;
  --bg-section:      #f5f8ff;
  --bg-card:         #ffffff;
  --text-primary:    #111827;
  --text-secondary:  #4b5563;
  --text-muted:      #9ca3af;
  --border-color:    #e5e7eb;
  --shadow-sm:       0 1px 3px rgba(0,0,0,.07), 0 1px 2px rgba(0,0,0,.04);
  --shadow-md:       0 4px 16px rgba(0,0,0,.08);
  --shadow-hover:    0 8px 28px rgba(41,212,103,.18);
  --radius-sm:       8px;
  --radius-md:       12px;
  --radius-lg:       20px;
  --font-sans:       'Inter', 'PingFang SC', 'Noto Sans SC', system-ui, sans-serif;
  --font-serif:      'Noto Serif SC', 'Source Han Serif SC', Georgia, serif;
  --transition:      0.2s ease;
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-sans);
  background: var(--bg-white);
  color: var(--text-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }

/* ============================================
   导航栏
   ============================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 17px;
  color: var(--text-primary);
  flex-shrink: 0;
}

.logo-symbol {
  width: 34px;
  height: 34px;
  background: linear-gradient(135deg, var(--green-primary), var(--green-dark));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  color: #fff;
}

.logo-text { font-family: var(--font-serif); }

.nav-links {
  display: flex;
  list-style: none;
  gap: 4px;
  align-items: center;
}

.nav-links a {
  padding: 6px 14px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
}

.nav-links a:hover { background: var(--green-light); color: var(--green-dark); }
.nav-links a.active { background: var(--green-light); color: var(--green-dark); font-weight: 600; }

/* ============================================
   Hero 区域
   ============================================ */
.hero {
  text-align: center;
  padding: 80px 24px 64px;
  background: linear-gradient(180deg, #f0fdf6 0%, #ffffff 100%);
  border-bottom: 1px solid #e8faf0;
}

.hero-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--green-dark);
  background: var(--green-light);
  border: 1px solid var(--green-mid);
  padding: 4px 14px;
  border-radius: 100px;
  margin-bottom: 20px;
  text-transform: uppercase;
}

.hero h1 {
  font-family: var(--font-sans);
  font-size: clamp(28px, 5vw, 48px);
  font-weight: 800;
  line-height: 1.25;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.hero-subtitle {
  font-size: clamp(15px, 2vw, 18px);
  color: var(--text-secondary);
  max-width: 520px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

/* 搜索框 */
.search-bar {
  display: flex;
  align-items: center;
  max-width: 480px;
  margin: 0 auto 32px;
  background: var(--bg-white);
  border: 1.5px solid var(--border-color);
  border-radius: 100px;
  padding: 10px 20px;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.search-bar:focus-within {
  border-color: var(--green-primary);
  box-shadow: 0 0 0 3px rgba(41,212,103,.15);
}

.search-icon { font-size: 15px; margin-right: 10px; opacity: 0.5; }

.search-bar input {
  flex: 1;
  border: none;
  outline: none;
  font-size: 15px;
  background: transparent;
  color: var(--text-primary);
  font-family: var(--font-sans);
}

.search-bar input::placeholder { color: var(--text-muted); }

/* 统计数字 */
.hero-stats {
  display: flex;
  gap: 32px;
  justify-content: center;
  color: var(--text-secondary);
  font-size: 14px;
}

.stat-num {
  display: inline-block;
  font-size: 22px;
  font-weight: 700;
  color: var(--green-dark);
  margin-right: 4px;
}

/* ============================================
   主体内容区
   ============================================ */
.main-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 56px 24px 80px;
}

/* ---- 分类标题 ---- */
.section-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  margin-top: 56px;
}

.section-header:first-child { margin-top: 0; }

.section-icon {
  width: 36px;
  height: 36px;
  background: var(--green-light);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  flex-shrink: 0;
}

.section-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.section-count {
  font-size: 12px;
  font-weight: 600;
  color: var(--green-dark);
  background: var(--green-light);
  padding: 2px 10px;
  border-radius: 100px;
  border: 1px solid var(--green-mid);
}

/* ---- 卡片网格 ---- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
  margin-bottom: 8px;
}

/* ---- 单张卡片 ---- */
.card {
  background: var(--bg-card);
  border: 1.5px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
  cursor: pointer;
}

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

.card-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.4;
}

.card-excerpt {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.65;
  flex: 1;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 4px;
}

.tag {
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 100px;
  background: #f3f4f6;
  color: var(--text-secondary);
  letter-spacing: 0.01em;
}

.tag.gold {
  background: #fef3c7;
  color: #92400e;
}

.tag.purple {
  background: #f3e8ff;
  color: #6b21a8;
}

.tag.green {
  background: var(--green-light);
  color: var(--green-dark);
}

/* ============================================
   文章页
   ============================================ */
.article-container {
  max-width: 760px;
  margin: 0 auto;
  padding: 48px 24px 80px;
}

.article-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  padding: 6px 14px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  margin-bottom: 32px;
  transition: var(--transition);
}

.article-back:hover {
  background: var(--green-light);
  color: var(--green-dark);
  border-color: var(--green-mid);
}

.article-header {
  margin-bottom: 40px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--border-color);
}

.article-category {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--green-dark);
  background: var(--green-light);
  border: 1px solid var(--green-mid);
  display: inline-block;
  padding: 3px 12px;
  border-radius: 100px;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.article-title {
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.3;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.article-meta {
  font-size: 13px;
  color: var(--text-muted);
}

/* ---- 文章正文 ---- */
.article-body {
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--text-secondary);
}

.article-body h2 {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  margin: 36px 0 14px;
  letter-spacing: -0.01em;
}

.article-body h2:first-child { margin-top: 0; }

.article-body h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  margin: 24px 0 10px;
}

.article-body p {
  margin-bottom: 16px;
}

.article-body ul,
.article-body ol {
  padding-left: 20px;
  margin-bottom: 16px;
}

.article-body li { margin-bottom: 6px; }

.article-body strong { color: var(--text-primary); font-weight: 600; }

.article-body em { color: var(--green-dark); font-style: normal; font-weight: 500; }

.article-body blockquote {
  background: var(--green-light);
  border-left: 4px solid var(--green-primary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 16px 20px;
  margin: 24px 0;
  color: var(--text-secondary);
  font-size: 14.5px;
}

.article-body hr {
  border: none;
  border-top: 1px solid var(--border-color);
  margin: 36px 0;
}

/* ---- 表格 ---- */
.article-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  font-size: 14px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  border: 1px solid var(--border-color);
}

.article-body th {
  background: #f9fafb;
  color: var(--text-primary);
  font-weight: 600;
  padding: 11px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
  font-size: 13px;
}

.article-body td {
  padding: 10px 14px;
  border-bottom: 1px solid #f3f4f6;
  color: var(--text-secondary);
  vertical-align: top;
}

.article-body tr:last-child td { border-bottom: none; }
.article-body tr:hover td { background: #f9fafb; }

/* ============================================
   分类导航页（Hero in pages）
   ============================================ */
.page-hero {
  text-align: center;
  padding: 56px 24px 40px;
  background: linear-gradient(180deg, #f0fdf6 0%, #ffffff 100%);
  border-bottom: 1px solid #e8faf0;
}

/* ============================================
   页脚
   ============================================ */
.site-footer {
  background: linear-gradient(135deg, #1ab855 0%, #0e9e44 100%);
  padding: 40px 24px;
  text-align: center;
  color: rgba(255,255,255,0.9);
}

.footer-inner {
  max-width: 600px;
  margin: 0 auto;
}

.site-footer p {
  font-size: 14px;
  line-height: 1.7;
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .card-grid { grid-template-columns: 1fr; }
  .hero { padding: 56px 20px 40px; }
  .main-container { padding: 40px 20px 60px; }
  .article-container { padding: 32px 20px 60px; }
  .hero-stats { gap: 20px; flex-wrap: wrap; justify-content: center; }
}