How do I change the default .htm file icon?

I want to change generally the default .htm file icon in the default theme in zorin, How I can do that?

Go into whatever it is you're using for icons and change it out with what it is you want to use.

I did it , i go to the directory of the theme icon which i use, and search for all html.png and text-html.png items and replace them with new icon with the same name,then refresh desktop