# Shadow DOM

By default Pillar components don't use Shadow DOM because polyfill for it in some browsers may be a
bit expensive. If you know what you doing and want to use Shadow DOM, all you need to do is pass an
options object with `useShadow` when registering:

```javascript
Pillar.register(MyComponent, 'my-component', {
	useShadow: 'open',
});
```

### Modes

* `useShadow: 'open'` will enable Shadow DOM that is accessible from outside JavaScript.
* `useShadow: 'closed'` will enable Shadow DOM that is unaccessible and unchangeable from
	JavaScript. As such, these elements can't be controlled using
	[Pillar DevTools](./6_DEVTOOLS.html).

**_Next: [Pillar DevTools →](./6_DEVTOOLS.html)_**