I have same problem
On Desktop, outer section of category looks fine
but when i open a category, then flag is aligned on the left instead of center.
It gets worse in mobile, again, flag aligned left
Are you using the Category Banners theme component? If not, then this may be a separate issue.
「いいね！」 1
It doesn’t look like you have that component installed. Let’s split this off into its own topic. 
「いいね！」 2