/* 裁音魔方 · 页面样式（自 pages/help.html 抽取，修改后请同步对应页面） */
        :root {
            --primary: #4CAF50;
            --primary-light: #81C784;
            --primary-dark: #388E3C;
            --secondary: #8BC34A;
            --accent: #CDDC39;
            --dark-bg: #121212;
            --darker-bg: #0A0A0A;
            --card-bg: #1E1E1E;
            --card-light: #252525;
            --card-border: #333333;
            --text-primary: #FFFFFF;
            --text-secondary: #B0B0B0;
            --success: #4CAF50;
            --warning: #FF9800;
            --error: #F44336;
            --gradient: linear-gradient(135deg, var(--primary), var(--primary-dark));
        }
        
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Poppins', 'Segoe UI', sans-serif;
        }
        
        body {
            background-color: var(--darker-bg);
            color: var(--text-primary);
            line-height: 1.6;
            overflow-x: hidden;
        }
        
        a {
            text-decoration: none;
            color: inherit;
        }
        
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        
        /* 页面头部 */
        .page-header {
            padding: 160px 0 80px;
            background: linear-gradient(180deg, var(--darker-bg) 0%, rgba(18, 18, 18, 0.9) 100%);
            position: relative;
            overflow: hidden;
            text-align: center;
        }
        
        .page-header::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: radial-gradient(circle at 50% 30%, rgba(76, 175, 80, 0.1) 0%, transparent 50%);
        }
        
        .page-header h1 {
            font-size: 48px;
            font-weight: 700;
            line-height: 1.2;
            margin-bottom: 20px;
            background: linear-gradient(90deg, var(--primary), var(--accent));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        
        .page-header p {
            font-size: 18px;
            color: var(--text-secondary);
            max-width: 700px;
            margin: 0 auto;
        }
        
        /* 主要内容区域 */
        .main-content {
            padding: 80px 0 100px;
        }
        
        .content-card {
            background-color: var(--card-bg);
            border-radius: 16px;
            padding: 50px;
            border: 1px solid var(--card-border);
            margin-bottom: 40px;
        }
        
        .content-card h2 {
            font-size: 32px;
            color: var(--primary);
            margin-bottom: 25px;
            padding-bottom: 15px;
            border-bottom: 2px solid rgba(76, 175, 80, 0.2);
        }
        
        .content-card h3 {
            font-size: 24px;
            color: var(--text-primary);
            margin: 30px 0 15px;
        }
        
        .content-card h4 {
            font-size: 18px;
            color: var(--primary-light);
            margin: 20px 0 10px;
        }
        
        .content-card p {
            color: var(--text-secondary);
            margin-bottom: 15px;
            line-height: 1.8;
        }
        
        .content-card ul, .content-card ol {
            margin: 15px 0 20px 25px;
            color: var(--text-secondary);
        }
        
        .content-card li {
            margin-bottom: 10px;
            line-height: 1.7;
        }
        
        .content-card a {
            color: var(--primary);
            transition: color 0.3s;
        }
        
        .content-card a:hover {
            color: var(--accent);
            text-decoration: underline;
        }
        
        /* 帮助中心特定样式 */
        .help-category {
            background-color: var(--card-light);
            border-radius: 12px;
            padding: 30px;
            margin-bottom: 25px;
            border-left: 5px solid var(--primary);
        }
        
        .category-header {
            display: flex;
            align-items: center;
            margin-bottom: 20px;
        }
        
        .category-icon {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 50px;
            height: 50px;
            background: var(--gradient);
            color: white;
            border-radius: 10px;
            font-size: 22px;
            margin-right: 15px;
        }
        
        .category-title {
            font-size: 24px;
            font-weight: 600;
        }
        
        .faq-item {
            background-color: rgba(255, 255, 255, 0.05);
            border-radius: 8px;
            padding: 20px;
            margin-bottom: 15px;
            cursor: pointer;
            transition: all 0.3s;
            border: 1px solid transparent;
        }
        
        .faq-item:hover {
            background-color: rgba(255, 255, 255, 0.08);
            border-color: var(--primary);
        }
        
        .faq-question {
            font-weight: 500;
            font-size: 18px;
            color: var(--text-primary);
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        
        .faq-question i {
            transition: transform 0.3s;
            color: var(--primary);
        }
        
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease-out;
            color: var(--text-secondary);
            margin-top: 0;
        }
        
        .faq-item.active .faq-answer {
            max-height: 500px;
            margin-top: 15px;
        }
        
        .faq-item.active .faq-question i {
            transform: rotate(180deg);
        }
        
        /* 提示框样式 */
        .tip-box {
            background-color: rgba(255, 152, 0, 0.1);
            border-left: 5px solid var(--warning);
            padding: 20px;
            border-radius: 8px;
            margin: 20px 0;
        }
        
        .tip-box h4 {
            color: var(--warning);
            margin-top: 0;
        }
        
        /* 响应式设计 */
        @media (max-width: 992px) {
            .page-header h1 {
                font-size: 40px;
            }
        }
        
        @media (max-width: 768px) {
            .page-header {
                padding: 140px 0 60px;
            }
            
            .page-header h1 {
                font-size: 36px;
            }
            
            .content-card {
                padding: 30px 20px;
            }
            
            .content-card h2 {
                font-size: 28px;
            }
            
            .category-header {
                flex-direction: column;
                align-items: flex-start;
            }
            
            .category-icon {
                margin-bottom: 10px;
            }
        }
        
        @media (max-width: 576px) {
            .page-header {
                padding: 120px 0 40px;
            }
            
            .btn {
                padding: 10px 20px;
                font-size: 14px;
            }
            
            .content-card {
                padding: 25px 15px;
            }
        }