With VIMP 4.1 CSS and JS files are being concatenated to reduce the number of server requests.
In order to apply your changes in the CSS files (e.g. style.css) you need to execute the following steps:
If npm is not installed yet on your server, please refer to this article.
In case you have a custom template or custom CSS or JS files that should be concatenated as well, please open the Grunt file (Gruntfile.js) within the templates folder before running the npm command and add new lines for your own template or your own CSS files analogous to the pacific and atlantic directives.
Changes in the skin files (for example business.css) are not concatenated and override CSS rules of style.css. Thus, when you edit a skin CSS file, you do not need to perform the above steps.