There are several CSS classes you can use to customize the appearance of Omnisearch.

```css
.omnisearch-modal
.omnisearch-result
.omnisearch-result__title
.omnisearch-result__counter
.omnisearch-result__body
.omnisearch-highlight
.omnisearch-input-container
.omnisearch-input-field
```
*This is list is not exhaustive, some classes might be added as Omnisearch is evolving.*