The meaning is the text Contact (for example) just under the heading foto in color,
and the button I will link to a mail adress, as there is also under the adress.
I hope its clear, I can’t copie a picture here.
You can adjust the color code #f00 as per your requirement.
If you are referring to link the mail address, you can follow this link: https://www.w3schools.com/tags/tryit.asp?filename=tryhtml_link_mailto