If you have siteground hosting (could be the same for other hosts) and maybe WordPress site and you just edited a style.css file, reloaded your page but you cant see the changes (they appear after some time) then it is probably a Super Cacher issue.
Go to your siteground cpanel, find SuperCacher under Site Improvement Tools and click it.
Then find your domain, click Flush Cache then turn it Off.
Here is some more info:
So one approach you could use is this : turn off cache while you are editing the files (through FTP, not in wordpress admin) site. Once you are done just turn it on again.