Found here those beautiful icons: https://themekit.dev/docs/code/iconsmind/

What do I need to use them? I added following lines to head

<link rel="stylesheet" href="themekit/css/bootstrap-grid.css">
<link rel="stylesheet" href="themekit/css/style.css">

<script src="themekit/scripts/jquery.min.js"></script>
<script src="themekit/scripts/main.js"></script>

and this to body:

<span className={"im-affiliate"}></span>

Nothing appeared.

I expected this icon: