You could do something like this.
[component="categories/category"] .fa-stack {
margin-right: 5px;
.fa-circle::before {
content: "\0000a0";
width: 24px;
background-color: rebeccapurple;
display: block;
border-radius: 5px;
}
}
It's kindof a hack, you would need to modify the theme to get real control. Also, there's no way to get the category background.
