Missing Vimeo social media icon missing in header area of Artcore html template


I seem to be unable to get a Vimeo icon to display in the social media icons area. The link appears, but the icon does not display. When the cursor is placed over the area where the icon should be (a blank space), the link to the social media site is displayed, but the icon is missing. It almost seems as though the icon is the same color as the header area it is located in. If anyone has any suggestions or fixes, it would be much appreciated. Thanks in advance!