Browser cache/Server Cache?

So what happened is that I updated some style ( lets say background color ) in my code, updated all the change through ftp(filezilla) and then i went into the plugin setting and clicked on both delete cache & delete cache and minified css/js button.

I opened another tab and when into see if the change is made on the website, but I couldn’t see the change until I actually refreshed the page, then I was able to see this.

How can I solve this problem? I want all the users to be able to see the change everytime I make any change.

Thank you

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