How can I add two packs of IcoMoon icons to the site?

Question

css

Hi
I went to a project where icons are already connected with fonts, and I need to add a couple more. How can this be done, because initialization is already underway?

[class^="icon-"], [class*=" icon-"] {
    /* use !important to prevent issues with browser extensions that change fonts */
    font-family: 'icomoon' !important;
    speak: none;
    font-style: normal;
    font-weight: normal;
    font-variant: normal;
    text-transform: none;
    line-height: 1;

Tried to add one more family to font-family - everything fell down. What to do?
Thanks