body {
            font-family: "Microsoft YaHei", Arial, sans-serif;
            max-width: 800px;
            margin: 0 auto;
            padding: 0px;
            transition: all 0.3s ease;
        }
        
        /* 顶部控制区样式 */
        .control-panel {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 0px;
            padding: 10px;
            background-color: #f8f9fa;
            border-radius: 5px;
        }
        
        .font-size-control {
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        .font-btn {
            width: 30px;
            height: 30px;
            border-radius: 50%;
            background-color: #e9ecef;
            display: flex;
            justify-content: center;
            align-items: center;
            cursor: pointer;
            transition: background-color 0.3s;
        }
        
        .font-btn:hover {
            background-color: #dee2e6;
        }
        
        /* 章节内容样式 */
        .chapter-content {
            line-height: 1.8;
            margin: 20px 0;
            font-size: 16px; /* 默认字体大小 */
            transition: font-size 0.3s ease;
        }
        
        .chapter-content p {
            margin-bottom: 1.5em;
            text-indent: 2em;
        }
        
        /* 章节标题样式 */
        .chapter-title {
            text-align: center;
            margin: 20px 0;
        }
        
        /* 导航按钮样式 */
        .navigation {
            display: flex;
            justify-content: space-between;
            margin-top: 30px;
        }
        
        .nav-btn {
            padding: 10px 15px;
            background-color: #007bff;
            color: white;
            border: none;
            border-radius: 5px;
            cursor: pointer;
            transition: background-color 0.3s;
        }
        
        .nav-btn:hover {
            background-color: #0056b3;
        }
        
        /* 加载状态样式 */
        .loading {
            color: #6c757d;
            text-align: center;
            padding: 50px 0;
            font-style: italic;
        }