I have seen a few websites that use the content attribute of a before/after pseudo element to set a picture as the content. The rule looks something like this:
:before {
content: "\e91b";
}
But then it is rendered as an image. I believe it is this setting because I can replace that escaped character with fooBar for instance and the image changes to that. And replacing the content will change it back. Changing the colour attribute changes the colour of the image so I'm guessing it is defined with some SVG data somewhere. These are obviously custom set characters because it will be set to the company's logo or other random things.
I'm honestly stumped on how this can be done and Google searching revealed nothing, though I'm not entirely sure what to search for. Everything I found referred to standard ISO characters that can be used in the escaped manner for easier typing/dev work.
Any help on this would be greatly appreciated.
It's called CSS pseudo elements, take a look at: https://fontawesome.com/how-to-use/on-the-web/advanced/css-pseudo-elements.