回答

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<head>
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<script type="text/javascript" src="//repo.bfw.wiki/bfwrepo/js/jquery-ui-1.11.0.min.js"></script>




    <style type="text/css">
        body{
            background: black;
        }
            .sortable {
                padding-left: 20px;
                border: 3px solid white;
                background: #FFCC33;
              
                margin: 10px;
            }
    </style>


</head>

<body>

    <div class="sortable">
        <div class="notsortable">Item 1 (disabled)</div>
        <div class="sortable">
            <div>Item 6.5.1</div>
            <div>Item 6.5.2</div>
            <div>Item 6.5.3</div>
            <div class="notsortable">Item 6.5.4 (disabled)</div>
            <div class="notsortable">Item 6.5.5 (disabled)</div>
            <div class="sortable">
                <div class="notsortable">Item 6.5.5.1 (disabled)</div>
                <div class="notsortable">Item 6.5.5.2 (disabled)</div>
            </div>
        </div>
        <div>Item 2</div>
        <div>Item 3</div>
        <div class="notsortable">Item 4 (disabled)</div>
        <div class="notsortable">Item 5 (disabled)</div>
        <div>Item 6
            <div class="sortable">
                <div class="notsortable">Item 6.1 (disabled)</div>
                <div class="notsortable">Item 6.2 (disabled)</div>
                <div>Item 6.3</div>
                <div>Item 6.4</div>
                <div>Item 6.5</div>
                <div class="sortable">
                    <div>Item 6.5.1</div>
                    <div>Item 6.5.2</div>
                    <div>Item 6.5.3</div>
                    <div class="notsortable">Item 6.5.4 (disabled)</div>
                    <div class="notsortable">Item 6.5.5 (disabled)</div>
                    <div class="sortable">
                        <div class="notsortable">Item 6.5.5.1 (disabled)</div>
                        <div class="notsortable">Item 6.5.5.2 (disabled)</div>
                    </div>
                </div>
            </div>
        </div>
        <div>Item 7</div>
    </div>


    <script type="text/javascript">
        $(function() {
            $( ".sortable" ).sortable({
            				connectWith: ".sortable",
        				    cancel: ".notsortable",
        				     tolerance: "pointer",
        				      cursorAt: { left: -50 }
            });
        });
    </script>




</body>

</html>