I know there are probably a billion answers to this that have been covered before.
i started out using a premade layout that has a hook for site width.
The site looks perfect when i don’t have a sidebar, it sits nicely centred, but when I add a sidebar it shrinks the content layout and tries to squeeze the content and the sidebar into the same width as previous. There seems to be as much white space width either side as there is in the centre where the content and sidebar is
Can you link us to the site you’re working on? So we can check it out and point you to the settings that has to be changed.
Note: The size of the content area is usually set on Appearance > Customize > Layout > Container. It’s the Container width you have to increase. A layout element found on Appearance > Elements can have this effect as well so that’s worth checking too. 🙂
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