[Product Addons] Customize the "Grand total" and "Options total"

wc-product-addons-grand-total.css

/*Options Total*/
.product-addon-totals dt:nth-child(1) { color:red;} 

/*Options Total Sum*/
.product-addon-totals dd:nth-child(2) { color:red;} 

/*Grand Total*/
.product-addon-totals dt:nth-child(3) { color:blue;}

/*Grand Total Sum*/
.product-addon-totals dd:nth-child(4) { color:blue;}