/* =========================================
           全局 & 基础变量 (加 case- 前缀避免冲突)
           ========================================= */
           :root {
            --case-bg-blue: #001880;
            --case-btn-cyan: #00AAFF;
            --case-text-white: #ffffff;
            --case-page-bg: #ffffff;
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
            font-family: "Microsoft YaHei", "Microsoft YaHei UI", sans-serif;
        }

        body {
            background-color: var(--case-page-bg);
            color: var(--case-text-white);
            line-height: 1.6;
            overflow-x: hidden;
        }

        img {
            max-width: 100%;
            height: auto;
            display: block;
        }

        /* 核心中心容器：1440px 居中 */
        .case-container {
            width: 100%;
            max-width: 1440px;
            margin: 0 auto;
            padding: 80px 20px;
            display: flex;
            flex-direction: column;
            gap: 60px; /* 卡片之间的上下间距 */
        }

        /* =========================================
           大横幅卡片 (横向布局)
           ========================================= */
        .case-wide-card {
            display: flex;
            flex-direction: row;
            background-color: var(--case-bg-blue);
            border-radius: 30px;
            overflow: hidden;
            box-shadow: 0 20px 40px rgba(0, 24, 128, 0.15);
        }

        /* 翻转排版：图片在右，文字在左 */
        .case-wide-card.reverse {
            flex-direction: row-reverse;
        }

        .case-wide-card-img {
            flex: 1;
            min-width: 320px;
        }

        .case-wide-card-img img {
            width: 100%;
            height: 100%;
            min-height: 400px;
            object-fit: cover;
        }

        .case-wide-card-content {
            flex: 1;
            padding: 60px 40px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center; /* 还原原代码中的居中对齐 */
            text-align: center;
            gap: 25px;
        }

        /* =========================================
           双列网格卡片 (纵向布局)
           ========================================= */
        .case-grid {
            display: flex;
            flex-direction: row;
            gap: 40px;
            flex-wrap: wrap;
        }

        .case-grid-card {
            flex: 1;
            min-width: 320px;
            background-color: var(--case-bg-blue);
            border-radius: 30px;
            overflow: hidden;
            display: flex;
            flex-direction: column;
            box-shadow: 0 20px 40px rgba(0, 24, 128, 0.15);
        }

        .case-grid-card-img {
            width: 100%;
            height: 400px;
        }

        .case-grid-card-img img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .case-grid-card-content {
            padding: 50px 40px;
            display: flex;
            flex-direction: column;
            align-items: center;
            text-align: center;
            gap: 25px;
            flex: 1;
            justify-content: center;
        }

        /* =========================================
           通用排版元素 (按钮、标题、描述)
           ========================================= */
        .case-tag-btn {
            background-color: var(--case-btn-cyan);
            color: var(--case-text-white);
            font-size: 14px;
            padding: 10px 30px;
            border-radius: 50px;
            cursor: pointer;
            display: inline-block;
            transition: opacity 0.3s;
        }

        .case-tag-btn:hover {
            opacity: 0.85;
        }

        .case-title {
            font-size: 30px;
            font-weight: bold;
            color: var(--case-text-white);
            line-height: 1.4;
        }

        .case-desc {
            font-size: 18px;
            color: var(--case-text-white);
            line-height: 31.5px; /* 还原原设计行高 */
            opacity: 0.9;
        }

        /* =========================================
           响应式适配
           ========================================= */
        @media (max-width: 992px) {
            /* 在屏幕较小时，解除左右交替，全部变为上下结构 */
            .case-wide-card, .case-wide-card.reverse {
                flex-direction: column;
            }
            .case-grid-card-img {
                height: 300px;
            }
            .case-wide-card-img img {
                min-height: 300px;
            }
        }

        @media (max-width: 768px) {
            .case-container {
                padding: 40px 20px;
                gap: 40px;
            }
            .case-title { font-size: 24px; }
            .case-desc { font-size: 16px; line-height: 1.6; }
            .case-wide-card-content, .case-grid-card-content {
                padding: 40px 20px;
            }
        }