.controls {
            display: flex;
            gap: 15px;
            margin-bottom: 20px;
            align-items: center;
        }
        .checkbox-container {
            display: flex;
            align-items: center;
            gap: 8px;
        }
        input[type="checkbox"] {
            width: 18px;
            height: 18px;
        }
        .input-group {
            margin-bottom: 20px;
        }
        label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: #555;
        }
        textarea {
            width: calc(100% - 28px);
            min-height: 120px;
            padding: 12px;
            border: 2px solid #ddd;
            border-radius: 6px;
            font-family: 'Courier New', monospace;
            font-size: 14px;
            resize: vertical;
            box-sizing: border-box;
        }
        textarea:focus {
            outline: none;
            border-color: #007acc;
        }
        .button-group {
            display: flex;
            gap: 10px;
            margin: 15px 0;
        }
        button {
            padding: 10px 20px;
            border: none;
            border-radius: 6px;
            cursor: pointer;
            font-size: 14px;
            font-weight: 600;
            transition: background-color 0.2s;
        }
        .btn-primary {
            background: #007acc;
            color: white;
        }
        .btn-primary:hover {
            background: #005a9e;
        }
        .btn-secondary {
            background: #6c757d;
            color: white;
        }
        .btn-secondary:hover {
            background: #545b62;
        }
        .btn-copy {
            background: #28a745;
            color: white;
            padding: 8px 16px;
            font-size: 12px;
        }
        .btn-copy:hover {
            background: #218838;
        }
        .output-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 8px;
        }
        .error {
            color: #dc3545;
            font-size: 14px;
            margin-top: 5px;
        }
        .success {
            color: #28a745;
            font-size: 14px;
            margin-top: 5px;
        }