Okay, I figured out how to change the icon size. It was only a matter of changing the button font size. I still have not figured out how to reduce the gap between the icons.
Try different values, so here is an example:
.bx-def-margin-right {
.margin-right: 0.5rem;
}
.bx-btn .sys-icon {
font-size: 2.5em;
Thanks