fix(navbar): Use :where() when setting navbar bg to ensure that uti…

…lity classes will win

inst/bs3compat/_navbar_compat.scss

@@ -117,13 +117,13 @@ ul.nav.navbar-nav {
     background-color: $navbar-bg;
   }
 
-  :where([data-bs-theme="dark"] .navbar) { @include navbar-background-dark(); }
-  :where([data-bs-theme="light"] .navbar, .navbar) { @include navbar-background-light(); }
+  [data-bs-theme="dark"] :where(.navbar) { @include navbar-background-dark(); }
+  [data-bs-theme="light"] :where(.navbar), :where(.navbar) { @include navbar-background-light(); }
 
   // These are defined *after* the above rules because we want the local version
   // to win without having to resort to specificity tricks.
-  :where(.navbar[data-bs-theme="dark"]) { @include navbar-background-dark(); }
-  :where(.navbar[data-bs-theme="light"]) { @include navbar-background-light(); }
+  :where(.navbar)[data-bs-theme="dark"] { @include navbar-background-dark(); }
+  :where(.navbar)[data-bs-theme="light"] { @include navbar-background-light(); }
 }
 
 // Implement bs3 navbar toggler; used in Rmd websites, i.e.