Keeping Colors Consistent on Macs and PCs

1. Make sure there is an embedded document profile.

2. Use a calibrator to make an accurate monitor profile.

This is basic color management and standard procedure regardless of Mac or Windows. If it's correct, it will match.

All major web browsers today support full color management.

You need to educate yourself about color management, how to use it and what the specific differences across different operating systems and devices are. That said, though, even if you do, you images will still look different across browsers. It's not like people use calibrated monitors to surf the web and mobile devices are not color managed, anyway. All you can do therefore is pretty much limited to setting up your own monitors to reflect a standard sRGB calibration and hope for the best for the rest.

Mylenium