How to change the background-color focus of the "tabs" in the "dropdown-menu"?

Question

I need to change the background-color focus of the "tabs" in the "dropdown-menu". Here it is "#section1" and "#section 2". After click bootstrap makes background of these sections blue. I need red. Help🙏
https://code.sololearn.com/WfSY7As4d8YS/?ref=app

Answer 1

#mybar .dropdown-menu li.active a {
background: red;
}

https://code.sololearn.com/WEkbqxU3I81k/?ref=app