/* 基础容器 */
  .delta-faq-section {
    padding: 90px 20px;
    background-color: transparent;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  }
  .delta-faq-container {
    max-width: 1200px;
    margin: 0 auto;
  }
  
  /* 模块总大标题区 */
  .faq-main-header {
    text-align: center;
    margin-bottom: 55px;
  }
  .faq-sub-tag {
    font-size: 11px;
    color: #005da6; /* Delta 蓝 */
    font-weight: 700;
    letter-spacing: 2.5px;
    display: block;
    margin-bottom: 12px;
  }
  .faq-main-header h2 {
    font-size: 36px;
    color: #111111;
    font-weight: 700;
    margin: 0 0 15px 0;
    letter-spacing: -0.5px;
  }
  .faq-title-line {
    width: 45px;
    height: 3px;
    background-color: #005da6;
    margin: 0 auto;
  }
  
  /* 双列瀑布流式大矩阵（PC端平分左右） */
  .delta-faq-matrix {
    display: flex;
    gap: 30px;
    align-items: flex-start;
  }
  .faq-matrix-column {
    flex: 1;
    width: 50%;
    display: flex;
    flex-direction: column;
    gap: 20px;
  }
  
  /* 单个风琴折叠卡片 */
  .faq-accordion-item {
    background: #ffffff;
    border: 1px solid #e2e8f0;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0,0,0,0.01);
    transition: all 0.3s ease;
  }
  
  /* 隐藏自带的原生复选框 */
  .faq-input {
    display: none;
  }
  
  /* 问题可触发点触区 */
  .faq-trigger {
    display: flex;
    align-items: flex-start;
    padding: 24px 28px;
    cursor: pointer;
    position: relative;
    user-select: none;
    background-color: #ffffff;
    transition: background-color 0.3s ease;
  }
  
  /* 字母 Q 标志样式 */
  .faq-q-letter {
    font-size: 18px;
    color: #005da6; /* 默认 Delta 蓝 */
    font-weight: 700;
    margin-right: 12px;
    line-height: 1.4;
    transition: color 0.3s ease;
  }
  
  /* 问题文字样式 */
  .faq-trigger h3 {
    font-size: 16px;
    color: #1e293b;
    font-weight: 600;
    margin: 0;
    line-height: 1.45;
    padding-right: 25px; /* 给右侧加号留出空间 */
    transition: color 0.3s ease;
  }
  
  /* 右侧纯 CSS 加减号转换图标 */
  .faq-arrow-icon {
    position: absolute;
    right: 28px;
    top: 28px;
    width: 14px;
    height: 14px;
  }
  .faq-arrow-icon::before, .faq-arrow-icon::after {
    content: "";
    position: absolute;
    background-color: #94a3b8;
    transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), background-color 0.3s ease;
  }
  /* 横条 */
  .faq-arrow-icon::before {
    top: 6px; left: 0; width: 14px; height: 2px;
  }
  /* 竖条 */
  .faq-arrow-icon::after {
    top: 0; left: 6px; width: 2px; height: 14px;
  }
  
  /* ================== 核心折叠动画控制（纯CSS控制高度） ================== */
  .faq-response-panel {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    background-color: #fafafa; /* 展开后答案带有极淡的技术灰质地背景 */
    border-top: 1px solid transparent;
  }
  .panel-inner-text {
    padding: 24px 28px 28px 28px;
    font-size: 14.5px;
    color: #475569;
    line-height: 1.65;
  }
  
  /* ================== 悬停（Hover）与激活（Checked）高级联动 ================== */
  
  /* 1. 鼠标滑过未展开的问题卡片 */
  .faq-accordion-item:hover {
    border-color: rgba(0, 93, 166, 0.25);
    box-shadow: 0 8px 20px rgba(0, 93, 166, 0.03);
  }
  .faq-accordion-item:hover .faq-trigger h3 {
    color: #C1272E; /* 悬停时激活专属点缀红 */
  }
  .faq-accordion-item:hover .faq-arrow-icon::before,
  .faq-accordion-item:hover .faq-arrow-icon::after {
    background-color: #C1272E;
  }
  
  /* 2. 复选框被勾选（即问题卡片被点击展开时） */
  .faq-input:checked ~ .faq-trigger {
    background-color: #ffffff;
  }
  .faq-input:checked ~ .faq-trigger h3 {
    color: #005da6; /* 展开后固定保持 Delta 蓝 */
  }
  .faq-input:checked ~ .faq-trigger .faq-q-letter {
    color: #C1272E; /* 字母 Q 变成点缀红 */
  }
  /* 展开时加号转化为减号：通过将竖条旋转成横向重叠实现 */
  .faq-input:checked ~ .faq-trigger .faq-arrow-icon::after {
    transform: rotate(90deg);
    opacity: 0;
  }
  .faq-input:checked ~ .faq-trigger .faq-arrow-icon::before {
    background-color: #005da6;
  }
  /* 激活下方答案面板展开 */
  .faq-input:checked ~ .faq-response-panel {
    max-height: 400px; /* 给予足够大的展开安全高度值 */
    border-color: #f1f5f9;
  }
  
  /* ================== RMA 有序流列表精细样式 ================== */
  .faq-inner-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 12px;
  }
  .faq-inner-list li {
    font-size: 14px;
    color: #475569;
    line-height: 1.5;
    display: flex;
    align-items: flex-start;
  }
  .faq-inner-list li span {
    background: rgba(0, 93, 166, 0.08);
    color: #005da6;
    font-size: 11px;
    font-weight: 700;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 12px;
    flex-shrink: 0;
    margin-top: 1px;
  }
  
  /* ================== 笔记本屏幕与中等设备适配 (1024px 以下) ================== */
  @media (max-width: 1024px) {
    .delta-faq-section { padding: 70px 25px; }
    .delta-faq-matrix { gap: 20px; }
    .faq-trigger { padding: 22px 24px; }
    .faq-arrow-icon { right: 24px; top: 25px; }
    .panel-inner-text { padding: 22px 24px 24px 24px; }
    .faq-trigger h3 { font-size: 15px; }
  }
  
  /* ================== 移动端手机屏幕完美适配 (768px 以下) ================== */
  @media (max-width: 768px) {
    .delta-faq-section { padding: 50px 15px; }
    .faq-main-header h2 { font-size: 26px; margin-bottom: 12px; }
    
    /* 核心改动：瓦解横向双列配置，将 10 个卡片合并成一条流畅的单向纵列流 */
    .delta-faq-matrix {
      flex-direction: column;
      gap: 15px;
    }
    .faq-matrix-column {
      width: 100%;
      flex: none;
      gap: 15px;
    }
    
    .faq-trigger { padding: 20px; }
    .faq-arrow-icon { right: 20px; top: 22px; }
    .panel-inner-text { padding: 18px 20px 22px 20px; font-size: 14px; }
    .faq-trigger h3 { font-size: 14.5px; padding-right: 20px; }
    
    /* 移动端下有序列表缩进和文字行高稍微加开，防止点按错乱 */
    .faq-inner-list { gap: 10px; }
    .faq-inner-list li { font-size: 13.5px; }
  }