body {
            font-family: Arial, sans-serif;
            margin: 0;
            padding: 0;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            background-color: #f4f4f4;
        }
        .container {
            text-align: center;
            background-color: white;
            padding: 20px;
            border-radius: 8px;
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
            width: 400px;
        }
        input[type="file"] {
            padding: 10px;
            font-size: 16px;
        }
        .btn-convert {
            background-color: #4CAF50;
            color: white;
            padding: 10px 20px;
            border: none;
            cursor: pointer;
            font-size: 16px;
            margin-top: 10px;
        }
        .btn-convert:hover {
            background-color: #45a049;
        }
        .result {
            margin-top: 20px;
        }