In years past your colleges added a line of code that invokes Font Awesome.
Here the ticket: https://www.joomlart.com/forums/d/35456-wrong-layout/9 where Ninja operator wrote me:
besides that it asked me to add some custom code:
@media(max-width:1092px) and (min-width:570px) {.products-toolbar .orderby-displaynumber .toolbar-amount {
left: 70%;
}}
@media (max-width: 568px){
.ja-megafilter-wrap .orderby-displaynumber #toolbar-amount {
display: none;
}}
that fixed the problems. Now there is this code and the old changes that your staff made. I therefore ask you to review what is needed to make what must work.
If the file to upload is another, upload it. If you need to insert a new link in the heder, give me the code and file wher put it, if you need to implement new css I need it.
Finally, I would like to remind you that the site already uses FontAwesome 5.
Here is an example of an icon that comes from there.