JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://dev.sencha.com/deploy/ext-3.3.1/resources/css/ext-all.css">
<script src="http://dev.sencha.com/deploy/ext-3.3.1/adapter/ext/ext-base.js"></script>
<script src="http://dev.sencha.com/deploy/ext-3.3.1/ext-all.js"></script>

JavaScript

var cc = new Ext.form.CompositeField({
       autoHeight: true
  // , renderTo: Ext.getBody()
       , autoWidth: true
       , items:[{
           xtype:'textfield'
           , flex: 1
           , growMax: 125
           , growMin: 80
           , width: 80
           , grow: true
        }}
        , {
           xtype:'textfield'
           , flex: 1
           , width: 80
        }]
     });

var ff = new Ext.form.FormPanel({
    items: cc,
    renderTo: Ext.getBody()
});