You can setup the links color for the entire website from the Customizer > General Styling section.
Change the Color of Links
Every site has a number of links, some referring to your own website pages known as internal links. A few links may be linking to other websites, known as external links.
To change the color of all these types of links, you can click on “Select Color” and choose your desired color from the color selection box in the links color section. You will be able to see the color changes in the live preview section of the theme customizer. If you like the colors you see just publish the page to save the changes.