The issue you're facing is that Bootstrap uses box-sizing: border-box for everything, while Kendo relies mostly on the default content-box sizing, which is supported in more browsers and resets the Bootstrap's CSS for everything contained in a Kendo Widget. To avoid this, you will need to set the Grid columns box-sizing yourself. Additionally Kendo PanelBar uses a div child of an item as a template container, so you better wrap your Bootstrap Grid in another div. Check the modified jsBin
for the result.
Join us on our journey to create the world's most complete HTML 5 UI Framework - download Kendo UI