:root {
            --primary: #2c3e50;
            --secondary: #0A71FF;
            --accent: #e74c3c;
            --light-bg: #f8f9fa;
            --text: #333;
            --light-text: #777;
            --border-color: #e0e0e0;
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        body {
            font-family: 'Helvetica Neue', 'Microsoft YaHei', sans-serif;
            line-height: 1.6;
            color: var(--text);
            background: white;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 30px 15px;
        }

        .section-header {
            text-align: center;
            margin-bottom: 30px;
        }

        .section-title {
            font-size: 1.5rem;
            margin-bottom: 12px;
            font-weight: 600;
            line-height: 1.3;
        }
        
        .center-title {
            color: var(--secondary);
        }

        .section-subtitle {
            font-size: 1rem;
            color: var(--light-text);
            max-width: 100%;
            margin: 0 auto;
            padding: 0 10px;
        }

        .solution-container {
            display: flex;
            flex-direction: column;
            gap: 15px;
            margin-top: 25px;
        }

        @media (min-width: 768px) {
            .container {
                padding: 40px 20px;
            }
            
            .section-title {
                font-size: 1.8rem;
            }
            
            .solution-container {
                flex-direction: row;
                align-items: flex-start;
                gap: 25px;
                margin-top: 30px;
            }
        }

        .solution-menu {
            width: 100%;
            order: 2;
        }

        @media (min-width: 768px) {
            .solution-menu {
                width: 45%;
                min-width: 350px;
                order: 1;
            }
        }

        @media (min-width: 992px) {
            .solution-menu {
                width: 430px;
            }
        }

        .solution-item {
            padding: 18px 20px;
            border-radius: 8px;
            margin-bottom: 8px;
            background: rgba(0, 0, 0, 0.02);
            transition: all 0.3s ease;
            cursor: pointer;
            border: 1px solid transparent;
        }

        .solution-item:hover {
            background: rgba(10, 113, 255, 0.05);
            border-color: rgba(10, 113, 255, 0.1);
        }

        .solution-item.selected {
            background: rgba(10, 113, 255, 0.08);
            border-color: var(--secondary);
        }

        .solution-item-content {
            display: flex;
            align-items: center;
        }

        .solution-icon {
            width: 30px;
            height: 30px;
            margin-right: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .solution-icon img {
            max-width: 100%;
            height: auto;
        }

        .solution-title {
            font-size: 1rem;
            font-weight: 500;
        }

        @media (min-width: 768px) {
            .solution-title {
                font-size: 1.1rem;
            }
        }

        .solution-preview {
            width: 100%;
            order: 1;
            margin-bottom: 20px;
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 2px 10px rgba(0,0,0,0.08);
        }

        @media (min-width: 768px) {
            .solution-preview {
                width: 55%;
                order: 2;
                margin-bottom: 0;
                flex-grow: 1;
            }
        }

        .solution-image {
            width: 100%;
            height: auto;
            display: block;
            transition: opacity 0.3s ease;
        }

        .fade-in {
            animation: fadeIn 0.5s ease-out;
        }

        @keyframes fadeIn {
            from { opacity: 0; }
            to { opacity: 1; }
        }

        /* 移动端优化 */
        @media (max-width: 767px) {
            .solution-item {
                padding: 15px;
            }
            
            .solution-icon {
                width: 25px;
                height: 25px;
                margin-right: 10px;
            }
            
            .solution-title {
                font-size: 0.95rem;
            }
        }