> For the complete documentation index, see [llms.txt](https://help.form.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.form.io/dev/css-frameworks.md).

# CSS Frameworks

The Form.io Renderer is very flexible and supports many different CSS frameworks. The following is a list of all the CSS frameworks supported by the Form.io Renderer. Click on each link to go to the page to view more documentation on each CSS framework integration.

## Bootstrap 3

{% embed url="<https://github.com/formio/bootstrap3>" %}

## Bootstrap 4

Bootstrap 4 is the default CSS framework for the Form.io Renderer. It comes with the renderer @

{% embed url="<https://github.com/formio/formio.js/tree/4.15.x>" %}

## Bootstrap 5

Bootstrap 5 CSS Framework is currently supported with formio.js renderer version 5.x.

{% embed url="<https://github.com/formio/formio.js/blob/main/package.json>" %}

## Semantic UI

{% embed url="<https://github.com/formio/semantic>" %}

## United States Web Design System

{% embed url="<https://github.com/formio/uswds>" %}

## UK Design System

{% embed url="<https://github.com/UKHomeOffice/formio-gds-template>" %}

## Bulma

{% embed url="<https://github.com/formio/bulma>" %}


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