StyleDecorator.ts
import { Decorator } from '@storybook/react';
import '../../../../app/styles/index.scss';

export const StyleDecorator: Decorator = Story => Story();

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previews.ts
import type { Preview } from '@storybook/react';
import { StyleDecorator } from '../../src/shared/config/storybook/StyleDecorator/StyleDecorator';

const preview: Preview = {
parameters: {
actions: { argTypesRegex: '^on[A-Z].*' },
controls: {
matchers: {
color: /(background|color)$/i,
date: /Date$/,
},
},
},
decorators: [StyleDecorator],
};
export default preview;