How to set size of kendo grid editor popup

I have defined a template for a kendo grid popup editor. Note: I need to use TagHelper not HtmlHelper

<editable mode="popup" template-id="popup-editor">
    <editable-window title="Add/Edit Collateral"/>
</editable>

This is the template

@using Kendo.Mvc.UI

@addTagHelper *, Kendo.Mvc

@model MyApp.Web.ViewModels.MyViewModel

<div id="divEditImpliedSupport">
    <form method="post" id="frmImpliedSupport" asp-action="SaveImpliedSupport" asp-controller="ReviewApi">
        <input type="hidden" asp-for="CollateralID" />
        <div class="row">
            <div>
                <formgroup>
                    <formlabel asp-for="CollateralDescription" ></formlabel>
                    <div>
                        <forminput asp-for="CollateralDescription" style="width:400px;"></forminput>
                    </div>
                </formgroup>
            </div>
        </div>
    </form>
</div>

How do I set the size of the popup window?

I was able to accomplish this with the following code where I define the popup editer.

<editable mode="popup" template-id="popup-editor">
    <editable-window title="Add/Edit Collateral" width="80%" />
</editable>