How to change border of select2 DDL or text color of selected value based on the forced selected value on load

Hello,
I have a select2 DDL, I bind the data using code behind and force a value to be added and selected. in addition to the list I bind to the select2 control
I tried changing the color of the forced selected value using code behind but with no luck.
I am trying to use java script to check if the value exists using a hidden filed and trying to either change the text color of the selected value or change the border of the dropdown to indicate to the users that a value was added to the select data list.
this can be accomplished with an ASO:DLL or html select control.
any help is appreciated