How to add custom CSS classes

Hi !
From [help page](https://www.hugobricks.preview.usecue.com/docs/customizations/css/), I am understanding that custom CSS definitions can be added to `/static/css/style.css`.

But let's say I have a brick like this:

```md
{{< brick_image >}}

# Accelerate digital transformation with DevOps excellence

Empower your projects with strategic DevOps solutions, aligning technology, processes, and people to achieve transformative business outcomes.

{{< button "Speak to our DevOps experts" "/contact/" >}}


{{< /brick_image >}}
```

This creates in HTML:
```html

...

```

How can I add additional classes to this section, besides `image` class so that I can link it to custom CSS ?

TY!