/* 全局基础设置 */
    body {
        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
        background-color: #f4f5f7; /* 底部非常柔和的浅灰背景 */
        color: #334155;
        line-height: 1.6;
        margin: 0;
        padding: 0;
        position: relative;
        min-height: 100vh;
        z-index: 0;
    }

    /* 🎨 核心：完全移除顶部的柔和红色背景色块 */

    /* 主内容区限制 */
    .container {
        max-width: 1100px;
        margin: 0 auto;
        padding: 60px 20px 80px 20px;
    }

    /* 页面标题 */
    .faq-header {
        text-align: center;
        margin-bottom: 50px;
        color: #1e293b; /* 在没有红底的情况下改为深色标题 */
    }
    .faq-header h1 {
        font-size: 2.8rem;
        margin: 0 0 15px 0;
        font-weight: 700;
        letter-spacing: -0.5px;
    }
    .faq-header p {
        color: #64748b; /* 改为柔和的灰色副标题 */
        font-size: 1.15rem;
        max-width: 600px;
        margin: 0 auto;
    }

    /* 整体容器 */
    .faq-wrapper {
        display: flex;
        gap: 30px;
        align-items: flex-start;
    }

    /* 左侧边栏分类导航 */
    .faq-sidebar {
        flex: 0 0 280px;
        background: #ffffff;
        border-radius: 16px;
        padding: 24px 0;
        box-shadow: 0 20px 40px -15px rgba(0, 0, 0, 0.08);
        position: sticky;
        top: 40px; 
        /* 顶部强调线，改为沉稳的红色 */
        border-top: 4px solid #dc2626;
    }

    .faq-sidebar ul {
        list-style: none;
        padding: 0;
        margin: 0;
    }

    .faq-sidebar li {
        padding: 16px 30px;
        font-size: 1.05rem;
        font-weight: 500;
        color: #64748b;
        cursor: pointer;
        transition: all 0.3s ease;
        position: relative;
    }

    .faq-sidebar li::before {
        content: '';
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 4px;
        background-color: #dc2626;
        transform: scaleY(0);
        transition: transform 0.3s ease;
    }

    .faq-sidebar li:hover {
        background-color: #fdf2f2; /* 非常浅的粉红/灰白底色 */
        color: #0f172a;
    }

    .faq-sidebar li.active {
        background-color: #fef2f2;
        color: #b91c1c; /* 激活时字体颜色较深，保证对比度 */
    }

    .faq-sidebar li.active::before {
        transform: scaleY(1);
    }

    /* 右侧内容区 */
    .faq-content {
        flex: 1;
        background: #ffffff;
        border-radius: 16px;
        padding: 40px;
        box-shadow: 0 20px 40px -15px rgba(0, 0, 0, 0.08);
    }

    .faq-section {
        display: none; 
        animation: fadeUp 0.5s ease-out forwards;
        opacity: 0;
        transform: translateY(15px);
    }
    .faq-section.active {
        display: block; 
    }

    .faq-category-title {
        font-size: 1.8rem;
        color: #0f172a;
        margin-top: 0;
        margin-bottom: 30px;
        padding-bottom: 15px;
        border-bottom: 2px solid #f1f5f9;
        display: flex;
        align-items: center;
        gap: 10px;
    }

    /* 标题前的彩色小方块 */
    .faq-category-title::before {
        content: '';
        display: inline-block;
        width: 12px;
        height: 24px;
        background: linear-gradient(135deg, #f87171, #dc2626);
        border-radius: 4px;
    }

    /* 折叠面板样式 */
    .faq-item {
        border: 1px solid #e2e8f0;
        border-radius: 10px;
        margin-bottom: 16px;
        overflow: hidden;
        transition: all 0.3s ease;
    }
    
    .faq-item:hover {
        border-color: #fca5a5;
        box-shadow: 0 4px 12px rgba(220,38,38,0.05);
    }

    .faq-question {
        padding: 20px 24px;
        background-color: #ffffff;
        cursor: pointer;
        font-size: 1.1rem;
        font-weight: 600;
        color: #1e293b;
        display: flex;
        justify-content: space-between;
        align-items: center;
        user-select: none;
        transition: background-color 0.3s ease, color 0.3s ease;
    }

    .faq-question:hover {
        color: #dc2626;
        background-color: #fdf2f2;
    }

    /* 展开/收起图标 */
    .faq-icon {
        width: 24px;
        height: 24px;
        border-radius: 50%;
        background-color: #f1f5f9;
        display: flex;
        align-items: center;
        justify-content: center;
        color: #64748b;
        font-size: 1.2rem;
        font-weight: 300;
        transition: all 0.3s ease;
    }

    .faq-item.active .faq-question {
        color: #b91c1c;
        background-color: #fef2f2;
        border-bottom: 1px solid #fee2e2;
    }

    .faq-item.active .faq-icon {
        background-color: #dc2626;
        color: #ffffff;
        transform: rotate(45deg);
    }

    .faq-answer {
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.4s cubic-bezier(0, 1, 0, 1), padding 0.4s ease;
        background-color: #fafbfc;
        color: #475569;
    }

    .faq-item.active .faq-answer {
        padding: 24px;
        max-height: 1000px;
        transition: max-height 0.5s ease-in-out, padding 0.3s ease;
    }

    .faq-answer p {
        margin: 0;
        white-space: pre-line;
        line-height: 1.7;
    }

    /* 动画 */
    @keyframes fadeUp {
        to { opacity: 1; transform: translateY(0); }
    }

    /* 响应式设计：移动端适配 */
    @media (max-width: 900px) {
        .faq-wrapper {
            flex-direction: column;
            gap: 20px;
        }
        
        .faq-sidebar {
            flex: auto;
            width: 100%;
            position: relative;
            top: 0;
            padding: 10px 0;
            border-top: none;
            border-left: 4px solid #dc2626; /* 移动端强调线换位置 */
        }

        .faq-sidebar ul {
            display: flex;
            overflow-x: auto;
            white-space: nowrap;
            scrollbar-width: none; 
            -ms-overflow-style: none;
        }
        .faq-sidebar ul::-webkit-scrollbar {
            display: none;
        }

        .faq-sidebar li {
            padding: 12px 20px;
        }

        .faq-sidebar li::before {
            display: none;
        }
        
        .faq-sidebar li.active {
            border-bottom: 3px solid #dc2626;
            background-color: transparent;
        }

        .faq-content {
            padding: 24px 20px;
        }
    }