/**
 * 电子乐器 - 电子书风格样式
 * 主题: 音乐制作、DAW、电子乐器教程
 * 主色调: #795548 (棕色系，适合阅读)
 */

/* ========== CSS 变量 ========== */
:root {
  --accent-color: #795548;
  --accent-light: #8d6e63;
  --accent-dark: #5d4037;
  --bg-primary: #faf8f5;
  --bg-secondary: #f5f2ed;
  --bg-card: #ffffff;
  --text-primary: #3e2723;
  --text-secondary: #6d4c41;
  --text-muted: #8d6e63;
  --border-color: #d7ccc8;
  --shadow: 0 2px 8px rgba(62, 39, 35, 0.08);
  --shadow-hover: 0 4px 16px rgba(62, 39, 35, 0.12);
  --radius: 8px;
  --radius-lg: 12px;
  --max-width: 1200px;
  --header-height: 64px;
}

/* ========== 重置与基础 ========== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
}

a {
  color: var(--accent-color);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

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

ul, ol {
  list-style: none;
}

/* ========== 布局容器 ========== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== 页头 ========== */
.header {
  background-color: var(--bg-card);
  border-bottom: 1px solid var(--border-color);
  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);
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo::before {
  content: "🎹";
  font-size: 1.25rem;
}

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

.nav a {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
}

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

.search-box {
  position: relative;
}

.search-box input {
  width: 240px;
  padding: 8px 16px 8px 40px;
  border: 1px solid var(--border-color);
  border-radius: 24px;
  background-color: var(--bg-primary);
  font-size: 0.9rem;
  transition: all 0.2s ease;
}

.search-box input:focus {
  outline: none;
  border-color: var(--accent-color);
  width: 280px;
}

.search-box::before {
  content: "🔍";
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 0.9rem;
  opacity: 0.6;
}

/* ========== Hero 区域 ========== */
.hero {
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
  padding: 80px 0 60px;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
}

.hero-title {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 32px;
}

.hero-tags {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.tag {
  padding: 6px 16px;
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* ========== 区块标题 ========== */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}

.section-title {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.section-title::before {
  content: "";
  width: 4px;
  height: 20px;
  background-color: var(--accent-color);
  border-radius: 2px;
}

.view-all {
  font-size: 0.9rem;
  color: var(--accent-color);
}

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

.section-alt {
  background-color: var(--bg-secondary);
}

/* ========== 卡片网格 ========== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
}

.card {
  background-color: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  overflow: hidden;
  transition: all 0.3s ease;
}

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

.card-cover {
  aspect-ratio: 16/10;
  background: linear-gradient(135deg, var(--accent-light) 0%, var(--accent-color) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
}

.card-body {
  padding: 20px;
}

.card-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 8px;
  line-height: 1.4;
}

.card-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: flex;
  gap: 12px;
}

.card-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 12px;
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ========== 分类网格 ========== */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px;
}

.category-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
  transition: all 0.2s ease;
}

.category-card:hover {
  border-color: var(--accent-color);
  background-color: var(--bg-secondary);
}

.category-icon {
  font-size: 2rem;
  margin-bottom: 12px;
}

.category-name {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

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

/* ========== 列表样式 ========== */
.list {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.list-item {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: flex-start;
  gap: 16px;
  transition: background-color 0.2s ease;
}

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

.list-item:hover {
  background-color: var(--bg-secondary);
}

.list-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--accent-light) 0%, var(--accent-color) 100%);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  flex-shrink: 0;
}

.list-content {
  flex: 1;
}

.list-title {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

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

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

.col-section {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
}

.col-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

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

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

.col-list a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

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

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

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

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

.breadcrumb span {
  margin: 0 8px;
}

/* ========== 分类页头部 ========== */
.category-header {
  background-color: var(--bg-secondary);
  padding: 40px 0;
  border-bottom: 1px solid var(--border-color);
}

.category-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.category-stats {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* ========== 筛选栏 ========== */
.filter-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 0;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 24px;
}

.filter-options {
  display: flex;
  gap: 8px;
}

.filter-btn {
  padding: 6px 16px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-card);
  border-radius: 20px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
}

.filter-btn:hover,
.filter-btn.active {
  background-color: var(--accent-color);
  border-color: var(--accent-color);
  color: white;
}

/* ========== 分页 ========== */
.pagination {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 40px;
}

.page-btn {
  min-width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-color);
  background-color: var(--bg-card);
  border-radius: var(--radius);
  font-size: 0.95rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
}

.page-btn:hover,
.page-btn.active {
  background-color: var(--accent-color);
  border-color: var(--accent-color);
  color: white;
}

/* ========== 文章页布局 ========== */
.article-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 40px;
  padding: 32px 0;
}

.article-main {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 40px;
}

.article-sidebar {
  position: sticky;
  top: 80px;
  height: fit-content;
}

/* ========== 文章内容 ========== */
.article-header {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

.article-title {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.4;
  margin-bottom: 16px;
}

.article-meta {
  display: flex;
  gap: 20px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.9;
  color: var(--text-primary);
}

.article-content h2 {
  font-size: 1.4rem;
  font-weight: 600;
  margin: 40px 0 20px;
  color: var(--text-primary);
}

.article-content h3 {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 32px 0 16px;
  color: var(--text-primary);
}

.article-content p {
  margin-bottom: 20px;
}

.article-content ul,
.article-content ol {
  margin-bottom: 20px;
  padding-left: 24px;
}

.article-content ul {
  list-style: disc;
}

.article-content ol {
  list-style: decimal;
}

.article-content li {
  margin-bottom: 8px;
}

.article-content code {
  background-color: var(--bg-secondary);
  padding: 2px 8px;
  border-radius: 4px;
  font-family: "SF Mono", Monaco, monospace;
  font-size: 0.9em;
  color: var(--accent-dark);
}

.article-content pre {
  background-color: #f5f5f5;
  padding: 20px;
  border-radius: var(--radius);
  overflow-x: auto;
  margin-bottom: 20px;
}

.article-content pre code {
  background: none;
  padding: 0;
}

/* ========== 目录 ========== */
.toc {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
}

.toc-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.toc-list li {
  padding: 8px 0;
  border-bottom: 1px dashed var(--border-color);
}

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

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

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

.toc-list .toc-h2 {
  padding-left: 0;
}

.toc-list .toc-h3 {
  padding-left: 16px;
  font-size: 0.85rem;
}

/* ========== 相关推荐 ========== */
.related-section {
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--border-color);
}

.related-title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.related-item {
  padding: 16px;
  background-color: var(--bg-secondary);
  border-radius: var(--radius);
  font-size: 0.9rem;
}

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

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

/* ========== 404 页面 ========== */
.error-page {
  min-height: calc(100vh - var(--header-height) - 200px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 24px;
}

.error-code {
  font-size: 8rem;
  font-weight: 700;
  color: var(--accent-color);
  line-height: 1;
  margin-bottom: 16px;
  opacity: 0.8;
}

.error-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 12px;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  background-color: var(--accent-color);
  color: white;
  border-radius: 24px;
  font-weight: 500;
  transition: all 0.2s ease;
}

.btn:hover {
  background-color: var(--accent-dark);
  color: white;
  transform: translateY(-1px);
}

/* ========== 页脚 ========== */
.footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 48px 0 24px;
  margin-top: 60px;
}

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

.footer-brand {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--accent-color);
  margin-bottom: 12px;
}

.footer-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.footer-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
}

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

.footer-links a {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

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

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ========== 响应式设计 ========== */
@media (max-width: 1024px) {
  .article-layout {
    grid-template-columns: 1fr;
  }

  .article-sidebar {
    position: static;
    order: -1;
  }

  .toc {
    margin-bottom: 24px;
  }

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

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

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

  .search-box input {
    width: 160px;
  }

  .search-box input:focus {
    width: 180px;
  }

  .hero {
    padding: 60px 0 40px;
  }

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

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

  .category-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

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

  .article-main {
    padding: 24px;
  }

  .article-title {
    font-size: 1.4rem;
  }

  .error-code {
    font-size: 5rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .filter-bar {
    flex-direction: column;
    gap: 16px;
    align-items: flex-start;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  .section {
    padding: 32px 0;
  }

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

  .list-item {
    flex-direction: column;
    gap: 12px;
  }
}