Close #3463388 Ensure foreground color is honored.

Closes #3463388

css/environment_indicator.css

@@ -55,6 +55,14 @@
   background-color: #EDEDE0;
 }
 
+.toolbar .toolbar-bar .toolbar-tab > a.toolbar-icon.is-active::before {
+  filter: invert(0%);
+}
+
+.toolbar .toolbar-bar .toolbar-tab > a.toolbar-icon.is-active {
+  background-image: linear-gradient(rgba(255,255,255,0.25) 20%,transparent 200%);
+}
+
 .toolbar-bar .toolbar-icon-environment:before {
   background-image: url("../images/env-bebebe.svg");
 }