No need to work on the first-child, work on the li directly

app/assets/stylesheets/scss/navbar.scss

@@ -134,7 +134,6 @@
 }
 
 nav.navbar .nav > li:not(.profile--image-dropdown) {
-  & > *:first-child {
   -moz-osx-font-smoothing: grayscale;
   position: relative;
 
@@ -159,17 +158,8 @@ nav.navbar .nav > li:not(.profile--image-dropdown) {
       height: 4px
     }
   }
-  }
 
-  &.active *:first-child:before {
+  &.active:before {
     height: 4px;
   }
-
-  & > .btn {
-    line-height: 50px;
-    width: 44px;
-    margin: 0;
-    border: 0;
-    padding: 0;
-  }
 }