I did changes to front end using Chrome tools/developer tools. I can see all the changes I made instantly.
I FTP to the site, downloaded the CSS file, did necessary changes (same as chrome developer changers) and uploaded the CCS file.
I access the site, but I cannot see the changes I made using CSS file.
also, in order to ensure that your CSS files are not cached suffix your php files like this
<link href="/stylesheet.css?<?php echo time(); ?>" rel="stylesheet" type="text/css" /&glt;
EDIT tip above also works for any resource! (css, javascript files, images ...)