CSS Not Updating

For some reason the style.css for my child theme for zeemagazine isn’t updating. It’s updated in the past, and if I change the version number for the style.css, that DOES update and the change is reflected in my dashboard, but changes to the content of the css (other than the header) don’t take any effect. I’ve even deleted everything except the css‘s required header, and my past modifications still remain. I’ve tried closing my browser, deleting my cookings, and even completely resetting my browser, and nothing works. Any ideas why this is happening?