CSS page caching
The browser cache is a regular folder on the hard drive that contains temporary files that are downloaded when you view the web page, and it is usually called
cache. The browser cache is used to quickly load pages on the Internet when they are visited again.
Modern browsers are designed in such a way that virtually all the information that a user requests on the Web (the Internet), they store on the local hard drive of the computer. This is done in order not to download the same files at every request of the user, that is to save traffic, as well as to speed up the work of the browser. The very process of storing frequently requested files is called caching. Using the cache allows the browser to load pages that the user has already accessed much faster, because most of the files that make up the Web page are already downloaded to the computer and instead of wasting time on Downloading files again, it gets the necessary files directly from the cache.
When you make changes to a file with external CSS style sheets, again loading the page to view the result of the changes just made, you will see that no changes have occurred. The fact is that when you load a web page, the browser does not always reload the data already in the cache, including external style sheets. Therefore, you will not be able to see what a Web page looks like by using the newly edited CSS from an external style sheet.
There are two ways to solve this problem: rename the CSS file or force the browser to reload the entire contents of the Web page (by simply manually updating the page) to allow the browser to update the cache files.
With this theme look: