h1 {
            color: #333;
        }
        #button-container {
            margin: 20px;
        }
        button {
            background-color: #4CAF50; /* Green */
            border: none;
            color: white;
            padding: 10px 20px;
            text-align: center;
            text-decoration: none;
            display: inline-block;
            font-size: 14px;
            margin: 5px;
            cursor: pointer;
            border-radius: 5px;
            transition: background-color 0.3s, transform 0.2s;
        }
        button:hover {
            background-color: #45a049; /* Darker green */
            transform: scale(1.05);
        }
        #content {
            margin-top: 0px;
            font-size: 18px;
            color: #555;
            border: 1px solid #ccc;
            padding: 10px;
            border-radius: 5px;
            background-color: #fff;
        }
        .sub-buttons {
            display: none; /* Hide by default */
            margin-top: 10px;
        }
        .sub-buttons button {
            font-size: 12px;
            padding: 8px 16px;
        }
        table {
            width: 100%;
            border-collapse: collapse;
            margin-top: 20px;
        }
        th, td {
            border: 1px solid #ccc;
            padding: 10px;
            text-align: left;
        }
        th {
            background-color: #f2f2f2;
        }