<!DOCTYPE html>
<html>

<head>
    <title>PK List Selection</title>
    <style>
        .pkContainer {
            display: flex;
            justify-content: center;
            align-items: center;
            /* height: 100vh; */
        }

        .pkBox {
            width: 150px;
            height: 200px;
            border: 1px solid #ccc;
            padding: 10px;
            margin: 10px;
            overflow-y: auto;
        }
    </style>
</head>

<body>
    <div class="pkContainer">
        <div class="pkBox">
            <!-- <h3>First Box</h3> -->
            <select id="pkFirstBox" multiple style="width: 150px; height: 200px;">
                <option value="item1">Item 1</option>
                <option value="item2">Item 2</option>
                <option value="item3">Item 3</option>
                <option value="item4">Item 4</option>
                <option value="item5">Item 5</option>
            </select>
        </div>
        <div class="pkBox">
            <!-- <h3>Second Box</h3> -->
            <select id="pkSecondBox" multiple style="width: 150px; height: 200px;"></select>
        </div>
    </div>
    <div class="pkContainer">
        <button onclick="pkMoveItems()">Add</button>
        <button onclick="pkMoveBack()">Back</button>
    </div>
    <script>
        function pkMoveItems() {
            var pkFirstBox = document.getElementById("pkFirstBox");
            var pkSecondBox = document.getElementById("pkSecondBox");

            // Move selected items from first box to second box
            for (var i = 0; i < pkFirstBox.options.length; i++) {
                var option = pkFirstBox.options[i];
                if (option.selected) {
                    pkSecondBox.appendChild(option);
                    i--;
                }
            }
        }

        function pkMoveBack() {
            var pkFirstBox = document.getElementById("pkFirstBox");
            var pkSecondBox = document.getElementById("pkSecondBox");

            // Move all items from second box back to first box
            while (pkSecondBox.options.length > 0) {
                pkFirstBox.appendChild(pkSecondBox.options[0]);
            }
        }
    </script>
</body>

</html>