The green check mark implies your system is secure and stable with its current updates, even when it indicates you're not up to date, usually means that your system is secure and functioning properly with the updates it currently has.
The yellow text indicates there are important updates available, but they might not be critical for immediate system security and stability.
Black only. Either bold or italics if you feel the need to add emphasis.
Most resumes are parsed by tools and you'll never see fancy formatting anyways.