Change orientation in Vue Menu component

<template>
<div>
<ejs-menu :items='menuItems' orientation='Vertical'></ejs-menu>
</div>
</template>

<script>
import Vue from 'vue';
import { MenuPlugin } from "@syncfusion/ej2-vue-navigations";
import { enableRipple } from '@syncfusion/ej2-base';

enableRipple(true);
Vue.use(MenuPlugin);

export default {
   data: function() {
        return {
           menuItems:  [
        {
        text: 'File',
        items: [
            { text: 'Open' },
            { text: 'Save' },
            { text: 'Exit' }
        ]
    },
    {
        text: 'Edit',
        items: [
            { text: 'Cut' },
            { text: 'Copy' },
            { text: 'Paste' }
        ]
    },
    {
        text: 'View',
        items: [
            { text: 'Toolbar' },
            { text: 'Sidebar' },
            { text: 'Full Screen' }
        ]
    },
    {
        text: 'Tools',
        items: [
            { text: 'Spelling & Grammar' },
            { text: 'Customize' },
            { text: 'Options' }
        ]
    },
    { text: 'Help' }
    ]
    };

    }
}
</script>

<style>
@import "../node_modules/@syncfusion/ej2-base/styles/material.css";
@import "../node_modules/@syncfusion/ej2-popups/styles/material.css";
@import "../node_modules/@syncfusion/ej2-navigations/styles/material.css";

body {
    margin-top: 100px;
    text-align: center;
}

</style>