> For the complete documentation index, see [llms.txt](https://doc-old.keycloakify.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc-old.keycloakify.dev/documentation/v11/customization-strategies/css-level-customization/using-custom-assets/plain-css.md).
# .css, .sass or .less
Let's see, as an example, the different ways you have to change the backgrounds image of the login page.
First let's [download a background image](https://coolbackgrounds.io/) an put it in our public directory:
{% hint style="info" %}
If you wish to do so, you can hot swipe assets that you have placed into your public directory in your Keycloak instance files at:
**/opt/keycloak/themes/**[**\**](/documentation/v11/configuration-options/themename.md)**/\/resources/dist**
{% endhint %}
Let's apply this image to the body using plain CSS
{% code title="src/login/main.css" %}
```css
body.kcBodyClass {
background: url(/background.png) no-repeat center center fixed;
}
```
{% endcode %}
We import the StyleSheet:
Result (see [testing your theme](/documentation/v11/testing-your-theme.md)):
Custom background successfully applied
If you prefer, you can also move the background.png image from `public/` to, for examples, `src/login/assets/background.png` and reference the image with a path relative to the CSS file, in this case it would be:
{% code title="src/login/main.css" %}
```css
body.kcBodyClass {
background: url(./assets/background.png) no-repeat center center fixed;
}
```
{% endcode %}
In the following video I show how to load different background for different page and how to create [theme variant](/documentation/v11/theme-variants.md).
{% embed url="" %}
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.
Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:
```
GET https://doc-old.keycloakify.dev/documentation/v11/customization-strategies/css-level-customization/using-custom-assets/plain-css.md?ask=&goal=
```
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Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
{% endhint %}
Let's apply this image to the body using plain CSS
{% code title="src/login/main.css" %}
```css
body.kcBodyClass {
background: url(/background.png) no-repeat center center fixed;
}
```
{% endcode %}
We import the StyleSheet:
