If you use external stylesheets, they are cached so they need not be downloaded for each page.
but as others have said, managing the sheets is necessary too so, in my view, it's better to have a 'default' stylesheet for the whole site and in that, put the css for the individual pages at the bottom, so you can get the best of both worlds - efficiency and easier management.
"The day you stop learning is the day you become obsolete"! - my late Dad.
Why do some people say "I don't know for sure"? If they don't know for sure then, they don't know!
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