Allow each component to have its own colors and default to the global set

sass/components/navbar.sass

@@ -46,6 +46,8 @@ $navbar-bottom-box-shadow-size: 0 -2px 0 0 !default
 
 $navbar-breakpoint: $desktop !default
 
+$navbar-colors: $colors !default
+
 =navbar-fixed
   left: 0
   position: fixed
@@ -57,7 +59,7 @@ $navbar-breakpoint: $desktop !default
   min-height: $navbar-height
   position: relative
   z-index: $navbar-z
-  @each $name, $pair in $colors
+  @each $name, $pair in $navbar-colors
     $color: nth($pair, 1)
     $color-invert: nth($pair, 2)
     &.is-#{$name}