jquery自动完成键值对搜索

Question

我的自动完成脚本有问题， 所需的结果是当我键入例如BG或BRIGHT GREEN以获得结果“BG”

时

    <?php

     $colours = 
                          [
                            'LG'=>'LIGHT GREEN',
                            'BG'=>'BRIGHT GREEN',
                            'DR'=>'DARK RED',
                            ];

    ?>
<link rel="stylesheet" href="https://code.jquery.com/ui/1.11.4/themes/smoothness/jquery-ui.css">
<script src="https://code.jquery.com/jquery-1.10.2.js"></script>
<script src="https://code.jquery.com/ui/1.11.4/jquery-ui.js"></script>
    <form id="frm" method="post">
    <input id="color" type="text" >
    </form>
        <script>
        var colorObj =  <?php echo json_encode($colours); ?>;
        $("#color").autocomplete({
            source:colorObj,
            minLength: 2,
            select: function(event, ui) {
                event.preventDefault();
                $("#color").val(ui.item.label);
            }
        });
        </script>