Flag Image

Hi, i would like to delete the flag icon in the language selector. I know how to do it if it were a widget (you can choose text with image, only image, only text) … However when I put the option to change the language in the menu of the header It comes out with the image of the flag and I would like to take it off

The site: http://escultura.es/en/

The page I need help with: [log in to see the link]