storybook/docs/snippets/common/storybook-preview-auto-docs-custom-docs-container.js.mdx

```js
// .storybook/preview.js

import { DocsContainer } from '@storybook/blocks';

const ExampleContainer = (props) => {
  const { children } = props;
  return (
    <DocsContainer {...props}>
      <div>
        <h1>Starter documentation</h1>
        <h2>Storybook's auto-generated documentation page uses this custom container.</h2>
        <div>{children}</div>
      </div>
    </DocsContainer>
  );
};

export const parameters = {
  actions: { argTypesRegex: '^on[A-Z].*' },
  controls: {
    matchers: {
      color: /(background|color)$/i,
      date: /Date$/,
    },
  },
  docs: {
    container: (props) => <ExampleContainer {...props} />,
  },
};
```