JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://cdn.kendostatic.com/2012.1.322/styles/kendo.common.min.css">
<link rel="stylesheet" href="http://cdn.kendostatic.com/2012.1.322/styles/kendo.default.min.css">
<script src="http://cdn.kendostatic.com/2012.1.322/js/kendo.all.min.js"></script>
<div id="grid"></div>

JavaScript

var items = [
    {
        "Item": "Item 1",
        "SubItems": [
            {
                "SubItem": "SubItem 1"
            },
            {
                "SubItem": "SubItem 2"
            }
        ]
    },
    {
        "Item": "Item 2",
        "SubItems": [
            {
                "SubItem": "SubItem 3"
            },
            {
                "SubItem": "SubItem 4"
            }
        ]
    }
];

$("#grid").kendoGrid({
    dataSource: items,
    detailInit: createDetail,
    columns: [
    { field: "Item", width: "200px" },
    ]
});

function createDetail(e) {
    $("<div/>")
        .appendTo(e.detailCell)
        .kendoGrid({
            dataSource: e.data.SubItems,
            editable:true,
            columns: [
                { field: "SubItem", title: "Sub Item", width: 200 }
            ]
        });
}