Hello
Kindly use the following mentioned CSS code in additional CSS
For Categories Sidebar
.widget_product_categories.sidebar-widget ul li a {
font-size: 14px;
}
.widget_product_categories.sidebar-widget ul li>ul.children li>a, .sidebar-widget ul li>ul.children li> a {
font-size: 14px;
}
For Brands
.sidebar-widget ul li a {
font-size: 14px;
}
Robert Hall