Bootstrap, can't change text colour

To change the color of your text in the navigation menu, you just have to add the following rule, what you already did  :

.navbar-inverse .navbar-nav > li > a {
    color: red
}

But however, there would be some remarks to certainly correct beforehand :

• you are using a version 3.4 of Bootstrap https://getbootstrap.com/docs/3.4/components/#navbar-default, today we are at version 5.+, you should eventually consider upgrading your site, especially since it seems that you are only at the beginning of its implementation.
• you use spaces in your access paths, these are shown by the presence of the %20 character which replaces them in the code, here too you should make sure you only use characters compatible with the sensitivity of the servers, even if there must be better and dedicated to the pure server, this reading can help you https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file 
• you use an http protocol to load your page, but you only refer to links to pages "embedded" from https... hence the errors of pages that do not load (bootstrap, jquery, to name a few...)

In conclusion, if the rule doesn't work to change the color, it's certainly because the code it contains is not interpreted, and that, just because the referent libraries are not loaded.

To verify it, just open the console (ctrl shift k) of your browser and copy and paste this following fragment

var css = '.navbar-inverse .navbar-nav > li > a {color: red;}';
var style = document.createElement('style');

if (style.styleSheet) {  style.styleSheet.cssText = css;} else {  style.appendChild(document.createTextNode(css));}

document.getElementsByTagName('head')[0].appendChild(style);

You will see that in plain JavaScript, without using jquery, it works, which demonstrates the loading problems related to the use of https,

First modify your requests by removing the s from https ( within the HEAD tag, for each SCRIPT and LINK tags)

Reaload you page, and it should work (of course, if you have added the rule quoted at the very beginning of this comment in your personal STYLE tag)

But then , second, think about adding a certificate to your page and use HTTPS