/* Book Layout Styles for Go Tutorial */

.book-layout {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: #f5f7fa;
}

.book-container {
  display: flex;
  min-height: 100vh;
  max-width: 1400px;
  margin: 0 auto;
}

/* 右侧顶部导航链接（备用） */
.book-right {
  position: fixed;
  top: 90px;
  right: 20px;
  width: 220px;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
  background: #ffffff;
  border: 1px solid #ecf0f1;
  border-radius: 10px;
  box-shadow: 0 6px 16px rgba(0,0,0,0.08);
  padding: 16px;
  z-index: 120;
}

.book-top-links h3 {
  margin: 0 0 12px 0;
  font-size: 14px;
  color: #2c3e50;
}

.book-top-links ul {
  list-style: none;
  padding: 0;
  margin: 0 0 8px 0;
}

.book-top-links li {
  margin: 6px 0;
}

.book-top-links a {
  color: #3498db;
  text-decoration: none;
  font-size: 13px;
}

.book-top-links a:hover {
  color: #2980b9;
}

.book-top-links .group-title {
  font-size: 13px;
  color: #2c3e50;
  margin-top: 10px;
  font-weight: 600;
}

.book-top-links .submenu {
  margin: 6px 0 0 10px;
}

/* 侧边栏样式 */
.book-sidebar {
  width: 280px;
  background: #2c3e50;
  color: #ecf0f1;
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  overflow-y: auto;
  z-index: 100;
  padding: 20px;
  box-shadow: 2px 0 8px rgba(0,0,0,0.1);
}

.book-brand {
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.book-brand h2 {
  color: #3498db;
  font-size: 24px;
  margin: 0;
  font-weight: 600;
}

.book-brand a {
  color: inherit;
  text-decoration: none;
}

.book-brand a:hover h2 {
  color: #5dade2;
}

.book-menu {
  font-size: 14px;
  line-height: 1.8;
}

.book-menu a {
  color: #bdc3c7;
  text-decoration: none;
  display: block;
  padding: 8px 12px;
  border-radius: 4px;
  transition: all 0.3s;
}

.book-menu a:hover {
  background: rgba(255,255,255,0.1);
  color: #3498db;
  padding-left: 16px;
}

.book-menu h1, .book-menu h2, .book-menu h3 {
  color: #ecf0f1;
  font-size: 16px;
  font-weight: 600;
  margin: 20px 0 10px 0;
}

.book-menu h3 {
  font-size: 14px;
  margin-left: 10px;
}

.book-menu ul {
  list-style: none;
  padding: 0;
  margin: 0 0 15px 0;
}

.book-menu li {
  margin: 5px 0;
}

.book-menu li.disabled {
  color: #7f8c8d;
  padding: 8px 12px;
  font-size: 14px;
  opacity: 0.6;
}

.menu-nav h3 {
  color: #3498db;
  font-size: 16px;
  margin-bottom: 15px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.menu-nav ul {
  list-style: none;
  padding: 0;
  margin: 0 0 20px 0;
}

.view-all {
  display: block;
  text-align: center;
  padding: 10px;
  background: rgba(52, 152, 219, 0.1);
  border-radius: 6px;
  color: #3498db;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s;
}

.view-all:hover {
  background: rgba(52, 152, 219, 0.2);
  transform: translateX(5px);
}

.menu-content {
  padding: 15px;
  background: rgba(52, 152, 219, 0.1);
  border-radius: 8px;
  text-align: center;
}

.menu-content a {
  color: #3498db;
  font-weight: 600;
  font-size: 16px;
}

/* 主内容区样式 */
.book-main {
  margin-left: 280px;
  margin-right: 260px;
  flex: 1;
  padding: 40px 60px;
  background: #fff;
  min-height: 100vh;
}

.book-content {
  max-width: 900px;
  margin: 0 auto;
}

#book-article {
  background: #fff;
  padding: 30px;
  border-radius: 8px;
}

.book-title {
  font-size: 36px;
  color: #2c3e50;
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 3px solid #3498db;
  font-weight: 700;
}

.book-body {
  font-size: 16px;
  line-height: 1.8;
  color: #34495e;
}

.book-body h1 {
  font-size: 32px;
  color: #2c3e50;
  margin: 40px 0 20px 0;
  padding-bottom: 10px;
  border-bottom: 2px solid #ecf0f1;
}

.book-body h2 {
  font-size: 28px;
  color: #34495e;
  margin: 35px 0 18px 0;
  padding-left: 12px;
  border-left: 4px solid #3498db;
}

.book-body h3 {
  font-size: 24px;
  color: #34495e;
  margin: 30px 0 15px 0;
}

.book-body h4 {
  font-size: 20px;
  color: #7f8c8d;
  margin: 25px 0 12px 0;
}

.book-body p {
  margin: 15px 0;
  text-align: justify;
}

.book-body a {
  color: #3498db;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: all 0.3s;
}

.book-body a:hover {
  color: #2980b9;
  border-bottom-color: #2980b9;
}

.book-body code {
  background: #f8f9fa;
  padding: 2px 6px;
  border-radius: 3px;
  font-family: 'Monaco', 'Menlo', 'Consolas', monospace;
  font-size: 14px;
  color: #e74c3c;
}

.book-body pre {
  background: #2c3e50;
  color: #ecf0f1;
  padding: 20px;
  border-radius: 6px;
  overflow-x: auto;
  margin: 20px 0;
  line-height: 1.6;
}

.book-body pre code {
  background: transparent;
  color: inherit;
  padding: 0;
  font-size: 14px;
}

.book-body ul, .book-body ol {
  margin: 15px 0;
  padding-left: 30px;
}

.book-body li {
  margin: 8px 0;
}

.book-body blockquote {
  border-left: 4px solid #3498db;
  padding: 15px 20px;
  margin: 20px 0;
  background: #f8f9fa;
  color: #7f8c8d;
  font-style: italic;
}

.book-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
}

.book-body table th {
  background: #3498db;
  color: #fff;
  padding: 12px;
  text-align: left;
  font-weight: 600;
}

.book-body table td {
  padding: 12px;
  border: 1px solid #ecf0f1;
}

.book-body table tr:nth-child(even) {
  background: #f8f9fa;
}

.book-body img {
  max-width: 100%;
  height: auto;
  border-radius: 6px;
  margin: 20px 0;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.book-body hr {
  border: none;
  border-top: 2px solid #ecf0f1;
  margin: 40px 0;
}

/* 页面导航 */
.book-navigation {
  display: flex;
  justify-content: space-between;
  margin-top: 60px;
  padding-top: 30px;
  border-top: 2px solid #ecf0f1;
}

.book-navigation a {
  padding: 12px 24px;
  background: #3498db;
  color: #fff;
  text-decoration: none;
  border-radius: 6px;
  transition: all 0.3s;
  font-weight: 600;
}

.book-navigation a:hover {
  background: #2980b9;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(52, 152, 219, 0.3);
}

.book-navigation .prev-page {
  margin-right: auto;
}

.book-navigation .next-page {
  margin-left: auto;
}

/* 响应式设计 */
@media (max-width: 1024px) {
  .book-sidebar {
    transform: translateX(-100%);
    transition: transform 0.3s;
  }
  
  .book-sidebar.active {
    transform: translateX(0);
  }
  
  .book-main {
    margin-left: 0;
    margin-right: 0;
    padding: 30px 20px;
  }

  .book-right {
    display: none;
  }
}

@media (max-width: 768px) {
  .book-title {
    font-size: 28px;
  }
  
  .book-body h1 {
    font-size: 26px;
  }
  
  .book-body h2 {
    font-size: 22px;
  }
  
  .book-body {
    font-size: 15px;
  }
  
  #book-article {
    padding: 20px;
  }
}

/* 滚动条样式 */
.book-sidebar::-webkit-scrollbar {
  width: 6px;
}

.book-sidebar::-webkit-scrollbar-track {
  background: rgba(255,255,255,0.1);
}

.book-sidebar::-webkit-scrollbar-thumb {
  background: rgba(255,255,255,0.3);
  border-radius: 3px;
}

.book-sidebar::-webkit-scrollbar-thumb:hover {
  background: rgba(255,255,255,0.5);
}