/* ===== 电子乐器 - 电子书风格样式 ===== */
/* 主色调: #795548 (棕色系) */

:root {
  --accent-color: #795548;
  --accent-light: #8d6e63;
  --accent-dark: #5d4037;
  --text-primary: #333;
  --text-secondary: #666;
  --text-muted: #999;
  --bg-primary: #fff;
  --bg-secondary: #fafafa;
  --bg-warm: #fdfbf7;
  --border-color: #e8e4e0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --max-width: 1200px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-serif: Georgia, "Times New Roman", serif;
}

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

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

body {
  font-family: var(--font-sans);
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-warm);
}

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

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

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

ul, ol {
  list-style: none;
}

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

.page-wrapper {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.main-content {
  flex: 1;
}

/* ===== Header ===== */
.header {
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--accent-color);
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--accent-color);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1.1rem;
}

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

.nav a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 8px 0;
  border-bottom: 2px solid transparent;
  transition: all 0.2s;
}

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

.search-box {
  display: flex;
  align-items: center;
  background: var(--bg-secondary);
  border-radius: 20px;
  padding: 6px 16px;
  width: 200px;
}

.search-box input {
  border: none;
  background: none;
  outline: none;
  font-size: 0.9rem;
  width: 100%;
  color: var(--text-primary);
}

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

.search-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.9rem;
}

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

.hero-title {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--accent-dark);
  margin-bottom: 16px;
  font-family: var(--font-serif);
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 32px;
  line-height: 1.8;
}

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

.tag {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.tag.primary {
  background: var(--accent-color);
  color: #fff;
  border-color: var(--accent-color);
}

/* ===== Section Title ===== */
.section-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--accent-color);
  display: inline-block;
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}

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

/* ===== Card Grid ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 24px;
  margin-bottom: 48px;
}

.card {
  background: var(--bg-primary);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
  transition: transform 0.2s, box-shadow 0.2s;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.card-cover {
  aspect-ratio: 4/3;
  background: var(--bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 3rem;
  position: relative;
  overflow: hidden;
}

.card-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.card-badge {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--accent-color);
  color: #fff;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 500;
}

.card-body {
  padding: 16px;
}

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

.card-meta {
  font-size: 0.875rem;
  color: var(--text-muted);
  display: flex;
  gap: 12px;
  align-items: center;
}

.card-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 8px;
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ===== Category List ===== */
.category-section {
  padding: 48px 0;
  background: var(--bg-primary);
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 16px;
}

.category-item {
  background: var(--bg-warm);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 20px;
  text-align: center;
  transition: all 0.2s;
}

.category-item:hover {
  background: var(--accent-color);
  border-color: var(--accent-color);
}

.category-item:hover .category-name,
.category-item:hover .category-count {
  color: #fff;
}

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

.category-name {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.category-count {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ===== List View ===== */
.list-section {
  padding: 48px 0;
}

.list-item {
  display: flex;
  gap: 20px;
  padding: 20px;
  background: var(--bg-primary);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  border: 1px solid var(--border-color);
  transition: box-shadow 0.2s;
}

.list-item:hover {
  box-shadow: var(--shadow-md);
}

.list-thumb {
  width: 120px;
  height: 90px;
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 2rem;
  overflow: hidden;
}

.list-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.list-content {
  flex: 1;
  min-width: 0;
}

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

.list-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 8px;
}

.list-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: flex;
  gap: 16px;
}

/* ===== Sidebar Layout ===== */
.sidebar-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 32px;
  padding: 32px 0;
}

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

.sidebar-widget {
  background: var(--bg-primary);
  border-radius: var(--radius-md);
  padding: 20px;
  margin-bottom: 20px;
  border: 1px solid var(--border-color);
}

.widget-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-color);
}

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

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

.widget-list a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  display: flex;
  justify-content: space-between;
}

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

.widget-list .count {
  color: var(--text-muted);
  font-size: 0.8rem;
}

/* ===== Breadcrumb ===== */
.breadcrumb {
  padding: 16px 0;
  font-size: 0.875rem;
  color: var(--text-muted);
}

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

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

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

.breadcrumb .current {
  color: var(--text-primary);
}

/* ===== Page Header ===== */
.page-header {
  background: var(--bg-primary);
  padding: 32px 0;
  border-bottom: 1px solid var(--border-color);
}

.page-title {
  font-size: 1.75rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.page-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ===== Filter Bar ===== */
.filter-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

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

.filter-btn {
  padding: 6px 14px;
  border: 1px solid var(--border-color);
  background: var(--bg-primary);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s;
}

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

.result-count {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* ===== Pagination ===== */
.pagination {
  display: flex;
  justify-content: center;
  gap: 8px;
  padding: 32px 0;
}

.pagination a,
.pagination span {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 36px;
  padding: 0 12px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  background: var(--bg-primary);
  transition: all 0.2s;
}

.pagination a:hover {
  background: var(--accent-color);
  color: #fff;
  border-color: var(--accent-color);
}

.pagination .current {
  background: var(--accent-color);
  color: #fff;
  border-color: var(--accent-color);
}

.pagination .disabled {
  color: var(--text-muted);
  cursor: not-allowed;
}

/* ===== Article Page ===== */
.article-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 40px;
  padding: 32px 0;
}

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

.toc-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--accent-color);
}

.toc-list {
  font-size: 0.9rem;
}

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

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

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

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

.toc-list .toc-h2 {
  padding-left: 0;
  font-weight: 500;
}

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

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

.article-header {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

.article-title {
  font-size: 1.75rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  line-height: 1.4;
  font-family: var(--font-serif);
}

.article-meta {
  display: flex;
  gap: 20px;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.article-meta span {
  display: flex;
  align-items: center;
  gap: 6px;
}

.article-body {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-primary);
}

.article-body h2 {
  font-size: 1.4rem;
  font-weight: 600;
  margin: 32px 0 16px;
  color: var(--text-primary);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
}

.article-body h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin: 24px 0 12px;
  color: var(--text-primary);
}

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

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

.article-body ul li {
  list-style: disc;
  margin-bottom: 8px;
}

.article-body ol li {
  list-style: decimal;
  margin-bottom: 8px;
}

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

.article-body blockquote {
  background: var(--bg-warm);
  border-left: 4px solid var(--accent-color);
  padding: 16px 20px;
  margin: 20px 0;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-secondary);
  font-style: italic;
}

.article-body code {
  background: var(--bg-secondary);
  padding: 2px 6px;
  border-radius: 3px;
  font-family: "SF Mono", Monaco, monospace;
  font-size: 0.9em;
  color: var(--accent-dark);
}

.article-body pre {
  background: var(--bg-secondary);
  padding: 16px;
  border-radius: var(--radius-sm);
  overflow-x: auto;
  margin: 20px 0;
}

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

/* ===== 404 Page ===== */
.error-page {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 20px;
}

.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;
  max-width: 400px;
}

.error-actions {
  display: flex;
  gap: 16px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
}

.btn-primary {
  background: var(--accent-color);
  color: #fff;
}

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

.btn-secondary {
  background: var(--bg-primary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

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

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

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

.footer-brand .logo {
  margin-bottom: 16px;
}

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

.footer-title {
  font-size: 1rem;
  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);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* ===== Three Column Section ===== */
.three-col-section {
  padding: 48px 0;
  background: var(--bg-primary);
  border-top: 1px solid var(--border-color);
}

.three-col-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.col-block {
  background: var(--bg-warm);
  border-radius: var(--radius-md);
  padding: 24px;
  border: 1px solid var(--border-color);
}

.col-block-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--accent-color);
}

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

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

.col-list a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  display: flex;
  justify-content: space-between;
}

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

.col-list .date {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .sidebar-layout,
  .article-layout {
    grid-template-columns: 1fr;
  }

  .sidebar,
  .toc-sidebar {
    position: static;
    order: -1;
  }

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

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

@media (max-width: 768px) {
  .header-inner {
    flex-wrap: wrap;
    height: auto;
    padding: 12px 0;
  }

  .nav {
    order: 3;
    width: 100%;
    gap: 16px;
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid var(--border-color);
    overflow-x: auto;
  }

  .search-box {
    width: 150px;
  }

  .hero {
    padding: 40px 0;
  }

  .hero-title {
    font-size: 1.75rem;
  }

  .hero-desc {
    font-size: 1rem;
  }

  .card-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

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

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

  .article-content {
    padding: 24px;
  }

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

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

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .card-grid {
    grid-template-columns: 1fr;
  }

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

  .filter-bar {
    flex-direction: column;
    gap: 12px;
    align-items: flex-start;
  }

  .error-actions {
    flex-direction: column;
  }
}