How to add 4 Columns in Footer?

This will be determined by settings in your Publii theme design. Plus, it depends what you mean by footer. Referring to the existing range of Publii themes shown at: https://marketplace.getpublii.com/themes/ , some of those themes include functionality to show teaser image links to 3 or 4 ‘Related Posts’  the lower area of post pages. For example, the TechNews theme demo shows this when you scroll to the end of posts:  https://demo.getpublii.eu/themes/technews/secrets-find-dron/ . Though, the bottom of a post is strictly the footer area — that would be lower still.

So if you wanted 4 columns to display for desktop devices, in the extreme lower area of the web pages, how you do that depends on which theme you’re using. Plus, of course, these high quality Publii themes usually automatically adjust themselves for best viewing on smaller screen mobile devices (responsive design), your mobile view would probably show only 2 columns or even 1 column (depends on the design settings) on mobile devices.

Which Publii theme are you using?

@kevin0425

There are different ways to extend the Documentation theme to get the result you want.

In the default free Documentation theme, looks like they allow for one footer menu in one column. Looks like you want 4 footer menus in 4 columns.

To make the chance, one approach that I would probably consider is, if you’re into coding (Handlebars, HTML, CSS), maybe study how GetPubli.com have done something similar at: https://getpublii.com/dev/

There are other, similar approaches in additional Publii themes too, including:

Lignes: https://marketplace.getpublii.com/themes/lignes/
Splitian: https://demo.getpublii.eu/themes/splitian/
Sources: https://demo.getpublii.eu/themes/sources/1/page/2/

So if you could mimic creating multiple footer menus in 4 columns, you would achieve your goal and still keep your Documentation theme responsive for both desktop and mobile viewing.

To preserve your changes when you update Publii and / or the default Documentation theme, you would probably want to do theme overrides: https://getpublii.com/dev/theme-overrides/

The above is the slower route but great for learning more about how to customise your theme further.

One quicker solution might be to check whether GetPublii.com can do the change for you: https://getpublii.com/customization-service/