How to highlight field if we check the field

Hi all, I want to highlight the field if i check the check column. I have a doctype name lead in which if i check lead is an organization i want to highlight organization name field and if i didnt check or bu default it should be person name.

i have added both the screenshot.
and below is the code which is working and adding 1 value in a field.

lead_is_an_organization: function(frm) {
if (frm.doc.lead_is_an_organization == 1) {
frm.set_value(‘company_name’, 1);
else {
frm.set_value(‘lead_name’, 1);