Hi There
This line will follow the settings of your website link colors which you can set up at Appereance / Customizer / Custom / CSS
If you will adjust your link colors to red, simply go there and change it and this line will also change automatically.
If that is not the case,
You can add the following code at your Appereance / Customizer / Custom / CSS
.x-navbar .desktop .x-nav>li>a:hover, .x-navbar .desktop .x-nav>.x-active>a, .x-navbar .desktop .x-nav>.current-menu-item>a {
color: red !important;
}
Hope that helps,
Joao