Hello, in OutSystems is it possible to create variables for the user to change between various themes created?

Exemple: Dark Theme or Light Theme.

The platform does not directly support this sort of functionality.

I have attempted this in the passed by dynamically including a separate CSS file which overrides all of the defined styles.  It does this by adding a class to body, eg class="DarkTheme" and each style has .DarkTheme added to the start of each definition.

It is not very maintainable, as you can imagine, because you have to keep the overriding theme up to date with each change to the main theme.

That was in Traditional Web Apps using Silk UI.  I do not really recommend it though.

A better approach, if it works for you is to do a limited change to the layout in the header and footer.

I hope this helps.  Let me know if you would like more detail.

Kind regards,



Hi Luciano,

You can do this using simple CSS and one small js script. Here is one example of doing this with css and js which you can implement in OutSystems.