/* ===== 基础变量 ===== */
:root {
  --accent-color: #8B4513;
  --accent-light: #D2691E;
  --bg-primary: #FAF7F2;
  --bg-secondary: #FFF;
  --text-primary: #333;
  --text-secondary: #666;
  --text-muted: #999;
  --border-color: #E8E0D5;
  --shadow: 0 2px 8px rgba(0,0,0,0.08);
  --radius: 8px;
  --max-width: 1200px;
  --header-height: 64px;
}

/* ===== 重置样式 ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

a {
  color: var(--accent-color);
  text-decoration: none;
}

a:hover {
  color: var(--accent-light);
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ===== 布局容器 ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== 页头 ===== */
.header {
  background: var(--bg-secondary);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent-color);
}

.nav {
  display: flex;
  gap: 32px;
}

.nav a {
  color: var(--text-primary);
  font-weight: 500;
  transition: color 0.2s;
}

.nav a:hover,
.nav a.active {
  color: var(--accent-color);
}

.search-box {
  display: flex;
  align-items: center;
  background: var(--bg-primary);
  border-radius: 20px;
  padding: 6px 16px;
}

.search-box input {
  border: none;
  background: transparent;
  outline: none;
  width: 160px;
  font-size: 0.9rem;
}

.search-box button {
  border: none;
  background: none;
  cursor: pointer;
  color: var(--text-muted);
}

/* ===== 面包屑 ===== */
.breadcrumb {
  padding: 16px 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.breadcrumb a {
  color: var(--text-secondary);
}

.breadcrumb a:hover {
  color: var(--accent-color);
}

.breadcrumb span {
  margin: 0 8px;
  color: var(--text-muted);
}

/* ===== Hero区域 ===== */
.hero {
  background: linear-gradient(135deg, var(--accent-color) 0%, var(--accent-light) 100%);
  color: #fff;
  padding: 80px 0;
  text-align: center;
}

.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.hero p {
  font-size: 1.1rem;
  opacity: 0.9;
  max-width: 600px;
  margin: 0 auto 32px;
}

.hero-btn {
  display: inline-block;
  background: #fff;
  color: var(--accent-color);
  padding: 12px 32px;
  border-radius: 24px;
  font-weight: 600;
  transition: transform 0.2s, box-shadow 0.2s;
}

.hero-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
  color: var(--accent-color);
}

/* ===== 内容区块 ===== */
.section {
  padding: 48px 0;
}

.section-title {
  font-size: 1.5rem;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.section-title::before {
  content: '';
  width: 4px;
  height: 24px;
  background: var(--accent-color);
  border-radius: 2px;
}

/* ===== 系列卡片 ===== */
.series-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}

.series-card {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform 0.2s, box-shadow 0.2s;
}

.series-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
}

.series-card-cover {
  height: 160px;
  background: linear-gradient(135deg, var(--border-color) 0%, #ddd 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 3rem;
}

.series-card-body {
  padding: 20px;
}

.series-card h3 {
  font-size: 1.1rem;
  margin-bottom: 8px;
}

.series-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 12px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.series-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ===== 文章列表 ===== */
.article-list {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.article-item {
  display: flex;
  gap: 16px;
  padding: 20px;
  border-bottom: 1px solid var(--border-color);
  transition: background 0.2s;
}

.article-item:last-child {
  border-bottom: none;
}

.article-item:hover {
  background: var(--bg-primary);
}

.article-thumb {
  width: 120px;
  height: 80px;
  background: var(--border-color);
  border-radius: 4px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
}

.article-info {
  flex: 1;
}

.article-info h4 {
  font-size: 1rem;
  margin-bottom: 6px;
}

.article-info p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 8px;
}

/* ===== 系列详情页 ===== */
.series-header {
  background: var(--bg-secondary);
  padding: 40px 0;
  margin-bottom: 32px;
}

.series-header-content {
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.series-cover {
  width: 280px;
  height: 180px;
  background: linear-gradient(135deg, var(--border-color) 0%, #ddd 100%);
  border-radius: var(--radius);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 4rem;
}

.series-info h1 {
  font-size: 1.8rem;
  margin-bottom: 12px;
}

.series-stats {
  display: flex;
  gap: 24px;
  margin-bottom: 16px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.series-desc {
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ===== 章节列表 ===== */
.parts-list {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.part-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-color);
  transition: background 0.2s;
}

.part-item:last-child {
  border-bottom: none;
}

.part-item:hover {
  background: var(--bg-primary);
}

.part-item.completed .part-num {
  background: var(--accent-color);
  color: #fff;
}

.part-num {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 600;
  flex-shrink: 0;
}

.part-content {
  flex: 1;
}

.part-content h4 {
  font-size: 1rem;
  margin-bottom: 4px;
}

.part-content span {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.part-check {
  color: var(--accent-color);
  font-weight: 600;
}

/* ===== 文章详情页 ===== */
.article-header {
  text-align: center;
  padding: 40px 0;
}

.article-header h1 {
  font-size: 1.8rem;
  margin-bottom: 12px;
}

.article-series-info {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.part-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 32px;
}

.part-nav a {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
}

.part-nav a:hover {
  color: var(--accent-color);
}

.part-nav-center {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.article-content {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 40px;
  box-shadow: var(--shadow);
  margin-bottom: 32px;
}

.article-content h2 {
  font-size: 1.4rem;
  margin: 32px 0 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--border-color);
}

.article-content h3 {
  font-size: 1.2rem;
  margin: 24px 0 12px;
}

.article-content p {
  margin-bottom: 16px;
  color: var(--text-secondary);
  line-height: 1.8;
}

.article-content img {
  width: 100%;
  border-radius: var(--radius);
  margin: 24px 0;
}

.article-content ul,
.article-content ol {
  margin: 16px 0;
  padding-left: 24px;
}

.article-content li {
  margin-bottom: 8px;
  color: var(--text-secondary);
}

/* ===== 进度条 ===== */
.progress-bar {
  background: var(--border-color);
  height: 8px;
  border-radius: 4px;
  overflow: hidden;
  margin: 16px 0;
}

.progress-fill {
  background: var(--accent-color);
  height: 100%;
  border-radius: 4px;
  transition: width 0.3s;
}

.progress-text {
  font-size: 0.9rem;
  color: var(--text-secondary);
  text-align: center;
}

/* ===== 侧边栏 ===== */
.sidebar-section {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 24px;
  box-shadow: var(--shadow);
}

.sidebar-section h3 {
  font-size: 1rem;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.sidebar-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--border-color);
}

.sidebar-list li:last-child {
  border-bottom: none;
}

.sidebar-list a {
  color: var(--text-primary);
  font-size: 0.9rem;
  display: block;
}

.sidebar-list a:hover {
  color: var(--accent-color);
}

/* ===== 三栏布局 ===== */
.three-col {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 32px;
}

.col-section {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow);
}

.col-section h3 {
  font-size: 1rem;
  margin-bottom: 16px;
  color: var(--accent-color);
}

.col-section li {
  padding: 8px 0;
  border-bottom: 1px solid var(--border-color);
}

.col-section li:last-child {
  border-bottom: none;
}

.col-section a {
  color: var(--text-primary);
  font-size: 0.9rem;
  display: block;
}

/* ===== 页脚 ===== */
.footer {
  background: var(--text-primary);
  color: #fff;
  padding: 48px 0 24px;
  margin-top: 48px;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 32px;
}

.footer-brand h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
}

.footer-brand p {
  color: #aaa;
  font-size: 0.9rem;
  line-height: 1.8;
}

.footer-links h4 {
  font-size: 1rem;
  margin-bottom: 16px;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: #aaa;
  font-size: 0.9rem;
}

.footer-links a:hover {
  color: #fff;
}

.footer-bottom {
  border-top: 1px solid #444;
  padding-top: 24px;
  text-align: center;
  color: #888;
  font-size: 0.85rem;
}

/* ===== 404页面 ===== */
.error-page {
  text-align: center;
  padding: 80px 20px;
}

.error-code {
  font-size: 8rem;
  font-weight: 700;
  color: var(--accent-color);
  line-height: 1;
  margin-bottom: 16px;
}

.error-title {
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.error-desc {
  color: var(--text-secondary);
  margin-bottom: 32px;
}

.error-btn {
  display: inline-block;
  background: var(--accent-color);
  color: #fff;
  padding: 12px 32px;
  border-radius: 24px;
  font-weight: 600;
}

.error-btn:hover {
  background: var(--accent-light);
  color: #fff;
}

/* ===== 响应式设计 ===== */
@media (max-width: 992px) {
  .series-header-content {
    flex-direction: column;
  }

  .series-cover {
    width: 100%;
    height: 200px;
  }

  .three-col {
    grid-template-columns: 1fr;
  }

  .footer-content {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav {
    display: none;
  }

  .search-box {
    display: none;
  }

  .hero {
    padding: 48px 0;
  }

  .hero h1 {
    font-size: 1.8rem;
  }

  .series-grid {
    grid-template-columns: 1fr;
  }

  .article-item {
    flex-direction: column;
  }

  .article-thumb {
    width: 100%;
    height: 160px;
  }

  .article-content {
    padding: 24px;
  }

  .part-nav {
    flex-direction: column;
    gap: 12px;
  }

  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
}