How to finalize the compiled CSS if you don’t want to write in bare CSS, but there are no SASS sources?

Question

css

Sometimes tasks arise: to create a new block for the site, to make a mobile version for an existing site, etc. And, as a rule, we only have FTP access to the server where the minified CSS is located. There is usually no gulp or webpack project.

How can you conveniently modify existing compiled style files using preprocessors and assemblers?

If I need to make a new block, I usually make it separate from the site for which this block is made, then I compile SCSS and paste it at the end of the existing CSS file. What to do if you need to modify, for example, the mobile version of the site? Is there any convenient way?

Answer 1

1. Need to import .css file to .scss
   
2. Use the compiled .css code optimization tool. For this, for example, cssnano is suitable . He knows how to remove repetitive pieces of code.