Cannot get CCS applied

WEB TMS WEB Core
22

I'm also struggling with changing the caption font color in WebPageControl.
I see:

.nav-link {
    display: block;
    padding: 0.5rem 1rem;
}
.nav-link {
    display: block;
    padding: 0.5rem 1rem;
    color: #0d6efd;
    text-decoration: none;
    transition: color .15s ease-in-out,background-color .15s ease-in-out,border-color .15s ease-in-out;

I have tried add CSS

.redButton2 {


    color: red !important ;

}

Also changing color in various parts of the myTheme.css didn't work.