```js
// MyComponent.stories.js

import { INITIAL_VIEWPORTS } from '@storybook/addon-viewport';

import MyComponent from './MyComponent.vue';

export default {
  /* 👇 The title prop is optional.
   * See https://storybook.js.org/docs/7.0/vue/configure/overview#configure-story-loading
   * to learn how to generate automatic titles
   */
  title: 'MyComponent',
  component: MyComponent,
  parameters: {
    //👇 The viewports object from the Essentials addon
    viewport: {
      //👇 The viewports you want to use
      viewports: INITIAL_VIEWPORTS,

      //👇 Your own default viewport
      defaultViewport: 'iphone6',
    },
  },
};

/*
 *👇 Render functions are a framework specific feature to allow you control on how the component renders.
 * See https://storybook.js.org/docs/7.0/vue/api/csf
 * to learn how to use render functions.
 */
export const MyStory = {
  render: () => ({
    components: { MyComponent },
    template: '<MyComponent />',
  }),
  parameters: {
    viewport: {
      defaultViewport: 'iphonex',
    },
  },
};
```