body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            margin: 40px;
            background-color: #f4f7f6;
            color: #333;
        }
        h1 {
            text-align: center;
            color: #2c3e50;
        }
        .pivot-table {
            width: 100%;
            border-collapse: collapse;
            margin-top: 20px;
            box-shadow: 0 4px 8px rgba(0,0,0,0.1);
            background-color: #fff;
        }
        .pivot-table th, .pivot-table td {
            border: 1px solid #e0e0e0;
            padding: 12px 15px;
            text-align: left;
        }
        .pivot-table thead th {
            background-color: #34495e;
            color: white;
            font-weight: 600;
            position: sticky;
            top: 0;
            z-index: 1;
        }
        .pivot-table tbody tr:nth-child(even) {
            background-color: #f8f9fa;
        }
        .pivot-table tbody tr:hover {
            background-color: #e9ecef;
        }
        .pivot-table td:first-child {
            font-weight: bold;
            background-color: #e9ecef; /* A slightly darker grey for better contrast */
            position: sticky;
            left: 0;
            z-index: 1;
            white-space: nowrap;
            width: 1%;
        }
        .pivot-table .section-title {
            background-color: #e2eafc; /* A light blue for section headers */
            color: #1c3d5a;
            font-weight: bold;
            text-align: left;
            padding: 10px 15px;
            border-top: 2px solid #34495e;
        }
        .pivot-table .food-plan-title {
            background-color: #d4edda; /* A distinct light green */
            color: #155724; /* A dark green for text */
            border-top: 2px solid #155724;
        }
        #pivot-table-container {
            overflow-x: auto;
            max-height: 80vh;
            border-radius: 8px;
        }
        .message {
            text-align: center;
            font-size: 1.1em;
            padding: 20px;
            border-radius: 5px;
        }
        .message.error {
            color: #721c24;
            background-color: #f8d7da;
            border: 1px solid #f5c6cb;
        }
        .message.info {
            color: #0c5460;
            background-color: #d1ecf1;
            border: 1px solid #bee5eb;
        }
        .tabs-container {
            display: flex;
            justify-content: center;
            margin-bottom: 20px;
        }
        .tab-button {
            padding: 10px 20px;
            margin: 0 5px;
            border: none;
            background-color: #e0e0e0;
            cursor: pointer;
            font-size: 16px;
            border-radius: 5px 5px 0 0;
        }
        .tab-button.active {
            background-color: #34495e;
            color: white;
        }