How do I remove calls for CSS in wordpress?

Hi I have two wordpress sites I'm working to optimize. using this to start.

I understand how to combine CSS into one minimized file, same with js. What I don't know is how to then remove the calls from the pages looking for the old files.

EG: site is techgardens dot com. I could ostensibly take all the css from the attached list of stylesheets and add them to my divi child style.css.

But then how do I get rid of all the calls for all the other stylesheets, in a way so that when I upgrade plugins and themes and wordpress, they don't come back? I hope that makes sense. thanks.
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Dave BaldwinFixer of ProblemsCommented:
I recommend that you simply don't do that.  Especially if your Wordpress site is set to auto-upgrade like most are these days.  The first time it upgrades, your site will be broken, possibly beyond repair.  It is not possible to make PageSpeed happy about everything.  It's more important that your site work.  The only real way to get rid of all those separate files is to not use all those plugins.

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You can place all of the plugin CSS in your child CSS and then you can wp_dequeue_style.  But like Dave said this could turn into an issue down the road:
Scott Fell, EE MVEDeveloper & EE ModeratorCommented:
mel200Author Commented:
Thanks all, very helpful comments. I'll leave it alone. :)
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