Combine and cache multiple CSS files for performance

This is a simple way to get a performance boost if you’re using PHP + Apache. I am using it to boost performance on GoToQuiz. If you are not using Apache, you can still use the PHP portion of this performance enhancement.

Some quick background: maintaining your site’s CSS in multiple files is frequently useful and sometimes necessary. But including multiple CSS files results in a performance hit when your pages load, because each one requires a separate request from the user’s browser to your server. Each request has associated overhead, which can be minimized if you send all CSS in one request.

This is how you can combine your CSS files with PHP and cache them, relying on a clever bit of .htaccess modification:

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