With modern pages in a Sharepoint Online collaboration site, content would be aligned center with white space on either sides but with Team sites the content is left aligned by default and plenty of white space on the right. However there is an easy fix to center align content in a Team site: 1. Navigate to the Settings from top right of the page by clicking the cog/gear wheel icon. 2. Select "Change the look" 3. Select Navigation from the options. 4. Select Horizontal as the option 5. Now the contents on all the pages will be aligned center. Note: This setting is site wide and not just for a page.
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