It is generally safe to include RewriteCond %{REQUEST_URI} !-f in rewrite rules so that these physical rules do not affect physical files such as css, js, images, etc.
However, in your case, none of your rules will affect these css, js, images files because you do not include the dot character . in the corresponding reular expression.
To overcome your problem, I recommend using the absolute path in your css, js, image files , and not in the relative. This means that you must make sure that the path to these files starts with http:// or a slash / .
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